#!/usr/bin/env rdmd
/+
- Name: Spine, Doc Reform
  - Description: documents, structuring, processing, publishing, search
    - static content generator

  - Author: Ralph Amissah
    [ralph.amissah@gmail.com]

  - Copyright: (C) 2015 - 2023 Ralph Amissah, All Rights
    Reserved.

  - License: AGPL 3 or later:

    Spine (SiSU), a framework for document structuring, publishing and
    search

    Copyright (C) Ralph Amissah

    This program is free software: you can redistribute it and/or modify it
    under the terms of the GNU AFERO General Public License as published by the
    Free Software Foundation, either version 3 of the License, or (at your
    option) any later version.

    This program is distributed in the hope that it will be useful, but WITHOUT
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
    more details.

    You should have received a copy of the GNU General Public License along with
    this program. If not, see [https://www.gnu.org/licenses/].

    If you have Internet connection, the latest version of the AGPL should be
    available at these locations:
    [https://www.fsf.org/licensing/licenses/agpl.html]
    [https://www.gnu.org/licenses/agpl.html]

  - Spine (by Doc Reform, related to SiSU) uses standard:
    - docReform markup syntax
      - standard SiSU markup syntax with modified headers and minor modifications
    - docReform object numbering
      - standard SiSU object citation numbering & system

  - Homepages:
    [https://www.doc_reform.org]
    [https://www.sisudoc.org]

  - Git
    [https://git.sisudoc.org/projects/?p=software/spine.git;a=summary]

+/
/+ dub.sdl
  name "spine search"
  description "spine cgi search"
+/
import std.format;
import std.range;
import std.regex;
import arsd.cgi;
import d2sqlite3;
import std.process : environment;
void cgi_function_intro(Cgi cgi) {
  mixin(import("configuration.txt"));
  string header;
  string table;
  string form;
  struct Config {
    string http_request_type;
    string http_host;
    // string server_name;
    string doc_collection_subroot;
    string cgi_script_name;
    string cgi_search_form_title;
    string cgi_search_form_html_title;
    string data_path_html;
    string http_url;
    string query_base_url;
    string query_string;
    string request_method;
    string db_path;
  }
  auto conf = Config();
  conf.http_request_type          = environment.get("REQUEST_SCHEME",        _cfg.http_request_type);
  conf.http_host                  = environment.get("SERVER_NAME",           _cfg.http_host);
  conf.doc_collection_subroot     = _cfg.www_url_doc_subroot;
  conf.cgi_script_name            = environment.get("SCRIPT_NAME",           _cfg.cgi_filename);
  conf.cgi_search_form_title      = _cfg.cgi_search_form_title; // ≅ SiSU spine search form
  conf.cgi_search_form_html_title = "<a href=\""
    ~ conf.http_request_type ~ "://"
    ~ conf.http_host
    ~ "\">"
    ~ _cfg.cgi_search_form_title
    ~ "</a>";
  conf.query_base_url          = conf.http_request_type ~ "://" ~ conf.http_host ~ conf.cgi_script_name ~ "?";
  conf.query_string            = environment.get("QUERY_STRING",          "");
  conf.http_url                = environment.get("HTTP_REFERER",          conf.query_base_url ~ conf.query_string);
  conf.request_method          = environment.get("REQUEST_METHOD",        "POST");
  conf.db_path                 = _cfg.db_sqlite_path;
  struct CGI_val {
    string db_selected      = "";
    string sql_match_limit  = "";     // radio: ( 1000 | 2500 )
    string sql_match_offset = "";
    string search_text      = "";
    string results_type     = "";     // index
    bool   checked_echo     = false;
    bool   checked_stats    = false;
    bool   checked_url      = false;
    bool   checked_searched = false;
    bool   checked_tip      = false;
    bool   checked_sql      = false;
  }
  auto cv = CGI_val();
  cv.db_selected = _cfg.db_sqlite_filename;
  auto text_fields() {
    string canned_query_str = environment.get("QUERY_STRING", "");
    if ("query_string" in cgi.post) {
      canned_query_str = environment.get("QUERY_STRING", "");
    }
    string[string] canned_query;
    if (conf.request_method == "POST") {
    } else if (conf.request_method == "GET") {
      foreach (pair_str; canned_query_str.split("&")) {
        // cgi.write(pair_str ~ "<br>");
        string[] pair = pair_str.split("=");
        canned_query[pair[0]] = pair[1];
      }
      // foreach (field, content; canned_query) {
      //   cgi.write(field ~ ": " ~ content ~ "<br>");
      // }
    }
    static struct Rgx {
      // static canned_query   = ctRegex!(`\A(?P<matched>.+)\Z`,                            "m");
      static search_text_area  = ctRegex!(`\A(?P<matched>.+)\Z`,                            "m");
      // static fulltext       = ctRegex!(`\A(?P<matched>.+)\Z`,                            "m");
      static line              = ctRegex!(`^(?P<matched>.+?)(?: ~|$)`,                      "m");
      static text              = ctRegex!(`(?:^|\s~\s*)text:\s+(?P<matched>.+?)(?: ~|$)`,   "m");
      static author            = ctRegex!(`(?:^|\s~\s*)author:\s+(?P<matched>.+)$`,         "m");
      static title             = ctRegex!(`(?:^|\s~\s*)title:\s+(?P<matched>.+)$`,          "m");
      static uid               = ctRegex!(`(?:^|\s~\s*)uid:\s+(?P<matched>.+)$`,            "m");
      static fn                = ctRegex!(`(?:^|\s~\s*)fn:\s+(?P<matched>.+)$`,             "m");
      static keywords          = ctRegex!(`(?:^|\s~\s*)keywords:\s+(?P<matched>.+)$`,       "m");
      static topic_register    = ctRegex!(`(?:^|\s~\s*)topic_register:\s+(?P<matched>.+)$`, "m");
      static subject           = ctRegex!(`(?:^|\s~\s*)subject:\s+(?P<matched>.+)$`,        "m");
      static description       = ctRegex!(`(?:^|\s~\s*)description:\s+(?P<matched>.+)$`,    "m");
      static publisher         = ctRegex!(`(?:^|\s~\s*)publisher:\s+(?P<matched>.+)$`,      "m");
      static editor            = ctRegex!(`(?:^|\s~\s*)editor:\s+(?P<matched>.+)$`,         "m");
      static contributor       = ctRegex!(`(?:^|\s~\s*)contributor:\s+(?P<matched>.+)$`,    "m");
      static date              = ctRegex!(`(?:^|\s~\s*)date:\s+(?P<matched>.+)$`,           "m");
      static results_type      = ctRegex!(`(?:^|\s~\s*)type:\s+(?P<matched>.+)$`,           "m");
      static format            = ctRegex!(`(?:^|\s~\s*)format:\s+(?P<matched>.+)$`,         "m");
      static source            = ctRegex!(`(?:^|\s~\s*)source:\s+(?P<matched>.+)$`,         "m");
      static language          = ctRegex!(`(?:^|\s~\s*)language:\s+(?P<matched>.+)$`,       "m");
      static relation          = ctRegex!(`(?:^|\s~\s*)relation:\s+(?P<matched>.+)$`,       "m");
      static coverage          = ctRegex!(`(?:^|\s~\s*)coverage:\s+(?P<matched>.+)$`,       "m");
      static rights            = ctRegex!(`(?:^|\s~\s*)rights:\s+(?P<matched>.+)$`,         "m");
      static comment           = ctRegex!(`(?:^|\s~\s*)comment:\s+(?P<matched>.+)$`,        "m");
      // static abstract_         = ctRegex!(`(?:^|\s~\s*)abstract:\s+(?P<matched>.+)$`,       "m");
      static src_filename_base = ctRegex!(`^src_filename_base:\s+(?P<matched>.+)$`,         "m");
    }
    auto rgx  = Rgx();
    struct searchFields {
      string canned_query      = ""; // GET  canned_query     == cq
      string search_text_area  = ""; // POST search_text_area == tsa
      string text              = ""; // text              == txt
      string author            = ""; // author            == au
      string title             = ""; // title             == ti
      string uid               = ""; // uid               == uid
      string fn                = ""; // fn                == fn
      string keywords          = ""; // keywords          == kw
      string topic_register    = ""; // topic_register    == tr
      string subject           = ""; // subject           == su
      string description       = ""; // description       == de
      string publisher         = ""; // publisher         == pb
      string editor            = ""; // editor            == ed
      string contributor       = ""; // contributor       == ct
      string date              = ""; // date              == dt
      string format            = ""; // format            == fmt
      string source            = ""; // source            == src sfn
      string language          = ""; // language          == lng
      string relation          = ""; // relation          == rl
      string coverage          = ""; // coverage          == cv
      string rights            = ""; // rights            == rgt
      string comment           = ""; // comment           == cmt
      // string abstract          = "";
      string src_filename_base = ""; // src_filename_base == bfn
      string results_type      = ""; // results_type      == rt     radio
      string sql_match_limit   = ""; // sql_match_limit   == sml    radio
      string sql_match_offset  = ""; // sql_match_offset  == smo
      string stats             = ""; // stats             == sts    checked
      string echo              = ""; // echo              == ec     checked
      string url               = ""; // url               == url    checked
      string searched          = ""; // searched          == se     checked
      string sql               = ""; // sql               == sql    checked
    }
    auto got  = searchFields();
    if (environment.get("REQUEST_METHOD", "POST") == "POST") {
      if ("sf" in cgi.post) {
        got.search_text_area =  cgi.post["sf"];
        if (auto m = got.search_text_area.matchFirst(rgx.text)) {
          got.text = m["matched"];
          got.canned_query ~= "sf=" ~ m["matched"];
        } else if (auto m = got.search_text_area.matchFirst(rgx.line)) {
          if (
            !(m["matched"].matchFirst(rgx.author))
            && !(m["matched"].matchFirst(rgx.title))
          ) {
            got.text = m["matched"];
            got.canned_query ~= "sf=" ~ m["matched"];
          }
        }
        if (auto m = got.search_text_area.matchFirst(rgx.author)) {
          got.author = m["matched"];
          got.canned_query ~= "&au=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.title)) {
          got.title = m["matched"];
          got.canned_query ~= "&ti=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.uid)) {
          got.uid = m["matched"];
          got.canned_query ~= "&uid=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.fn)) {
          got.fn = m["matched"];
          got.canned_query ~= "&fn=" ~ m["matched"];
        } else if ("fn" in cgi.post) {
          got.search_text_area ~= "\nfn: " ~ cgi.post["fn"] ~ "\n";
        }
        if (auto m = got.search_text_area.matchFirst(rgx.keywords)) {
          got.keywords = m["matched"];
          got.canned_query ~= "&kw=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.topic_register)) {
          got.topic_register = m["matched"];
          got.canned_query ~= "&tr=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.subject)) {
          got.subject = m["matched"];
          got.canned_query ~= "&su=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.description)) {
          got.description = m["matched"];
          got.canned_query ~= "&de=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.publisher)) {
          got.publisher = m["matched"];
          got.canned_query ~= "&pb=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.editor)) {
          got.editor = m["matched"];
          got.canned_query ~= "&ed=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.contributor)) {
          got.contributor = m["matched"];
          got.canned_query ~= "&ct=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.date)) {
          got.date = m["matched"];
          got.canned_query ~= "&dt=" ~ m["matched"];
        }
        // if (auto m = got.search_text_area.matchFirst(rgx.results_type)) {
        //   got.results_type = m["matched"];
        //   got.canned_query ~= "&rt=" ~ m["matched"];
        // }
        if (auto m = got.search_text_area.matchFirst(rgx.format)) {
          got.format = m["matched"];
          got.canned_query ~= "&fmt=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.source)) {
          got.source = m["matched"];
          got.canned_query ~= "&src=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.language)) {
          got.language = m["matched"];
          got.canned_query ~= "&lng=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.relation)) {
          got.relation = m["matched"];
          got.canned_query ~= "&rl=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.coverage)) {
          got.coverage = m["matched"];
          got.canned_query ~= "&cv=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.rights)) {
          got.rights = m["matched"];
          got.canned_query ~= "&rgt=" ~ m["matched"];
        }
        if (auto m = got.search_text_area.matchFirst(rgx.comment)) {
          got.comment = m["matched"];
          got.canned_query ~= "&cmt=" ~ m["matched"];
        }
        // if (auto m = search_text_area.matchFirst(rgx.abstract)) {
        //   got.abstract = m["matched"];
        // }
        if (auto m = got.search_text_area.matchFirst(rgx.src_filename_base)) {
          got.src_filename_base = m["matched"];
          got.canned_query ~= "&bfn=" ~ m["matched"];
        }
      }
      if ("fn" in cgi.post) {
        got.fn =  cgi.post["fn"];
        got.canned_query ~= "&fn=" ~ cgi.post["fn"];
      }
      if ("rt" in cgi.post) {
        got.results_type =  cgi.post["rt"];
        got.canned_query ~= "&rt=" ~ cgi.post["rt"];
      }
      if ("sts" in cgi.post) {
        got.stats =  cgi.post["sts"];
        got.canned_query ~= "&sts=" ~ cgi.post["sts"];
      }
      if ("ec" in cgi.post) {
        got.echo =  cgi.post["ec"];
        got.canned_query ~= "&ec=" ~ cgi.post["ec"];
      }
      if ("url" in cgi.post) {
        got.url =  cgi.post["url"];
        got.canned_query ~= "&url=" ~ cgi.post["url"];
      }
      if ("se" in cgi.post) {
        got.searched =  cgi.post["se"];
        got.canned_query ~= "&se=" ~ cgi.post["se"];
      }
      if ("sql" in cgi.post) {
        got.sql =  cgi.post["sql"];
        got.canned_query ~= "&sql=" ~ cgi.post["sql"];
      }
      if ("sml" in cgi.post) {
        got.sql_match_limit =  cgi.post["sml"];
        got.canned_query ~= "&sml=" ~ cgi.post["sml"];
      }
      if ("smo" in cgi.post) {
        got.sql_match_offset = "0";   // cgi.post["smo"];
        got.canned_query ~= "&smo=0"; //  ~ cgi.post["smo"];
      }
      got.canned_query = got.canned_query.strip.split(" ").join("%20");
      conf.query_string = got.canned_query;
      // cgi.write("f.canned_query: " ~ got.canned_query ~ "<br>");
    } else if (environment.get("REQUEST_METHOD", "POST") == "GET") {
      got.canned_query = environment.get("QUERY_STRING", "");
      // cgi.write("f.canned_query: " ~ got.canned_query ~ "<br>");
      got.search_text_area = "";
      if ("sf" in canned_query && !(canned_query["sf"]).empty) {
        got.text = canned_query["sf"].split("%20").join(" ");
        got.search_text_area ~= "text: " ~ got.text ~ "\n";
      }
      if ("au" in canned_query && !(canned_query["au"]).empty) {
        got.author = canned_query["au"].split("%20").join(" ");
        got.search_text_area ~= "author: " ~ got.author ~ "\n";
      }
      if ("ti" in canned_query && !(canned_query["ti"]).empty) {
        got.title = canned_query["ti"].split("%20").join(" ");
        got.search_text_area ~= "title: " ~ got.title ~ "\n";
      }
      if ("uid" in canned_query && !(canned_query["uid"]).empty) {
        got.uid = canned_query["uid"].split("%20").join(" ");
        got.search_text_area ~= "uid: " ~ got.uid ~ "\n";
      }
      if ("fn" in canned_query && !(canned_query["fn"]).empty) {
        got.fn = canned_query["fn"].split("%20").join(" ");
        got.search_text_area ~= "fn: " ~ got.fn ~ "\n";
      }
      if ("kw" in canned_query && !(canned_query["kw"]).empty) {
        got.keywords = canned_query["kw"].split("%20").join(" ");
        got.search_text_area ~= "keywords: " ~ got.keywords ~ "\n";
      }
      if ("tr" in canned_query && !(canned_query["tr"]).empty) {
        got.topic_register = canned_query["tr"].split("%20").join(" ");
        got.search_text_area ~= "topic_register: " ~ got.topic_register ~ "\n";
      }
      if ("su" in canned_query && !(canned_query["su"]).empty) {
        got.subject = canned_query["su"].split("%20").join(" ");
        got.search_text_area ~= "subject: " ~ got.subject ~ "\n";
      }
      if ("de" in canned_query && !(canned_query["de"]).empty) {
        got.description = canned_query["de"].split("%20").join(" ");
        got.search_text_area ~= "description: " ~ got.description ~ "\n";
      }
      if ("pb" in canned_query && !(canned_query["pb"]).empty) {
        got.publisher = canned_query["pb"].split("%20").join(" ");
        got.search_text_area ~= "publisher: " ~ got.publisher ~ "\n";
      }
      if ("ed" in canned_query && !(canned_query["ed"]).empty) {
        got.editor = canned_query["ed"].split("%20").join(" ");
        got.search_text_area ~= "editor: " ~ got.editor ~ "\n";
      }
      if ("ct" in canned_query && !(canned_query["ct"]).empty) {
        got.contributor = canned_query["ct"].split("%20").join(" ");
        got.search_text_area ~= "contributor: " ~ got.contributor ~ "\n";
      }
      if ("dt" in canned_query && !(canned_query["dt"]).empty) {
        got.date = canned_query["dt"].split("%20").join(" ");
        got.search_text_area ~= "date: " ~ got.date ~ "\n";
      }
      if ("rt" in canned_query && !(canned_query["rt"]).empty) {
        got.results_type = canned_query["rt"].split("%20").join(" ");
        // got.search_text_area ~= "results_type: " ~ got.results_type ~ "\n";
      }
      if ("fmt" in canned_query && !(canned_query["fmt"]).empty) {
        got.format = canned_query["fmt"].split("%20").join(" ");
        got.search_text_area ~= "format: " ~ got.format ~ "\n";
      }
      if ("src" in canned_query && !(canned_query["src"]).empty) {
        got.source = canned_query["src"].split("%20").join(" ");
        got.search_text_area ~= "source: " ~ got.source ~ "\n";
      }
      if ("lng" in canned_query && !(canned_query["lng"]).empty) {
        got.language = canned_query["lng"].split("%20").join(" ");
        got.search_text_area ~= "language: " ~ got.language ~ "\n";
      }
      if ("rl" in canned_query && !(canned_query["rl"]).empty) {
        got.relation = canned_query["rl"].split("%20").join(" ");
        got.search_text_area ~= "relation: " ~ got.relation ~ "\n";
      }
      if ("cv" in canned_query && !(canned_query["cv"]).empty) {
        got.coverage = canned_query["cv"].split("%20").join(" ");
        got.search_text_area ~= "coverage: " ~ got.coverage ~ "\n";
      }
      if ("rgt" in canned_query && !(canned_query["rgt"]).empty) {
        got.rights = canned_query["rgt"].split("%20").join(" ");
        got.search_text_area ~= "rights: " ~ got.rights ~ "\n";
      }
      if ("cmt" in canned_query && !(canned_query["cmt"]).empty) {
        got.comment = canned_query["cmt"].split("%20").join(" ");
        got.search_text_area ~= "comment: " ~ got.comment ~ "\n";
      }
      // if ("abstract" in canned_query && !(canned_query["abstract"]).empty) {
      //   got.abstract = canned_query["abstract"];
      // }
      if ("bfn" in canned_query && !(canned_query["bfn"]).empty) { // search_field
        got.src_filename_base = canned_query["bfn"].split("%20").join(" ");
        got.search_text_area ~= "src_filename_base: " ~ got.src_filename_base ~ "\n";
      }
      if ("sml" in canned_query && !(canned_query["sml"]).empty) {
        got.sql_match_limit = canned_query["sml"].split("%20").join(" ");
        // got.search_text_area ~= "sql_match_limit: " ~ got.sql_match_limit ~ "\n";
      }
      // cgi.write("f.search_text_area: " ~ got.search_text_area ~ "<br>");
    }
    return got;
  }
  auto tf = text_fields; //
  struct SQL_select {
    string the_body         = "";
    string the_range        = "";
  }
  auto sql_select = SQL_select();
  string canned_url () {
    string _url = "";
    if (environment.get("REQUEST_METHOD", "POST") == "POST") {
      _url = conf.query_base_url ~ tf.canned_query;
    } else if (environment.get("REQUEST_METHOD", "POST") == "GET") {
      _url = conf.query_base_url ~ environment.get("QUERY_STRING", "");
    }
    return _url;
  }
  auto regex_canned_search () {
    static struct RgxCS {
      static track_offset       = ctRegex!(`(?P<offset_key>[&]smo=)(?P<offset_val>[0-9]+)`);
      static results_type       = ctRegex!(`[&]rt=(?P<results_type>idx|txt)`);
      static results_type_index = ctRegex!(`[&]rt=idx`);
      static results_type_text  = ctRegex!(`[&]rt=txt`);
      static fn                 = ctRegex!(`[&]fn=(?P<fn>[^&]+)`);
    }
    return RgxCS();
  }
  string show_matched_objects (string fn) {
    auto rgx = regex_canned_search;
    string _matched_objects_text = "";
    string _url = canned_url;
    string _url_new = "";
    string _matches_show_text  = "&rt=txt";
    string _matches_show_index = "&rt=idx";
    string _fn = "&fn=" ~ fn;
    _url_new = _url;
    if (_url_new.match(rgx.results_type_index)) {
      _url_new = _url_new.replace(rgx.results_type_index, _matches_show_text);
    } else if (_url.match(rgx.results_type_text)) {
      _url_new = _url_new.replace(rgx.results_type_text, _matches_show_index);
    } else {
      if (!(_url.match(rgx.results_type))) {
        _url_new = _url ~ _matches_show_text;
      }
    }
    if (!(_url_new.match(rgx.fn))) {
      _url_new = _url_new ~ _fn;
    }
    _matched_objects_text =
      "<font-size=\"2rem\" color=\"#666666\">"
      ~ "<a href=\""
      ~ _url_new
      ~ "\">"
      ~ "፠"
      ~ "</a></font>";
    return _matched_objects_text;
  }
  string base; // = "";
  string tip; // = "";
  string search_note; // = "";
  uint   sql_match_offset_count = 0;
  string previous_next () {
    auto rgx = regex_canned_search;
    string _previous_next = "";
    int    _current_offset_value = 0;
    string _set_offset_next = "";
    string _set_offset_previous = "";
    string _url = canned_url;
    string _url_previous = "";
    string _url_next = "";
    string arrow_previous = "";
    string arrow_next = "";
    if (auto m = _url.matchFirst(rgx.track_offset)) {
      _current_offset_value = m.captures["offset_val"].to!int;
      _set_offset_next = m.captures["offset_key"] ~ ((m.captures["offset_val"]).to!int + cv.sql_match_limit.to!int).to!string;
      _url_next = _url.replace(rgx.track_offset, _set_offset_next);
      if (_current_offset_value < cv.sql_match_limit.to!int) {
        _url_previous = "";
      } else {
        _url_previous = "";
        _set_offset_previous = m.captures["offset_key"] ~ ((m.captures["offset_val"]).to!int - cv.sql_match_limit.to!int).to!string;
        _url_previous = _url.replace(rgx.track_offset, _set_offset_previous);
      }
    } else { // _current_offset_value = 0;
      _url_next = _url ~= "&smo=" ~ cv.sql_match_limit.to!string;
    }
    if (_url_previous.empty) {
      arrow_previous = "";
    } else {
      arrow_previous =
        "<font-size=\"1.8rem\" color=\"#666666\">"
        ~ "<a href=\""
        ~ _url_previous
        ~ "\">"
        ~ "❮❮ prev"
        ~ "</a> || </font>";
    }
    arrow_next =
      "<font-size=\"1.8rem\" color=\"#666666\">"
      ~ "<a href=\""
      ~ _url_next
      ~ "\">"
      ~ "next ❯❯"
      ~ "</a></font>";
    _previous_next = "<hr>" ~ arrow_previous ~ arrow_next;
    return _previous_next;
  }
  {
    header = format(q"┃
<!DOCTYPE html>
<html>
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  <title>
    %s
  </title>
  <meta name="sourcefile" content="SiSU.sst">
  <link rel="generator" href="sisudoc.org">
  <link rel="shortcut icon" href="%s://%s/image_sys/spine.ico">
  <style media = "all">
    html {
      font-size              : 62.5%%;
    }
    *{
      padding                  : 0px;
      margin                   : 2px;
    }
    body {
      height                   : 100vh;
      font-size                : 1.6rem;
      color                    : #000000;
      background               : #FFFFFF;
      background-color         : #FFFFFF;
    }
    a:link {
      color                    : #003399;
      text-decoration          : none;
    }
    a:visited {
      color                    : #003399;
      text-decoration          : none;
    }
    a:hover {
      color                    : #000000;
      background-color         : #F9F9AA;
    }
    a.matched_ocn:link {
      color                    : #003399;
      text-decoration          : none;
    }
    a.matched_ocn:visited {
      color                    : #003399;
      text-decoration          : none;
    }
    a.matched_ocn:hover {
      color                    : #000000;
      background-color         : #F9F9AA;
      font-size                : 1.6rem;
    }
    a.lnkocn:link {
      color                    : #777777;
      text-decoration          : none;
    }
    a.lnkocn:visited {
      color                    : #32CD32;
      text-decoration          : none;
    }
    a.lnkocn:hover {
      color                    : #777777;
      font-size                : 1.6rem;
    }
    a:hover img {
      background-color         : #FFFFFF;
    }
    a:active {
      color                    : #003399;
      text-decoration          : underline;
    }
    .flex-container {
      display                  : flex;
    }
    div.publication {
      margin-top               : 2px;
      margin-bottom            : 4px;
      margin-left              : 0%%;
      margin-right             : 0%%;
    }
    div.textview_ocn {
      margin-left              : 0%%;
      margin-right             : 1%%;
    }
    div.textview_found {
      margin-left              : 1%%;
      margin-right             : 1%%;
    }
    textarea {
      color                    : #000000;
      background-color         : #FFFFFF;
    }
    span.match {
      color                    : #000000;
      background-color         : #FFFF48;
    }
    input, select, textarea {
      font-size                : 2rem;
    }
    input[type="text"] {
      font-size                : 2rem;
      line-height              : 150%%;
    }
    button[type="submit"] {
      font-size                : 2rem;
      line-height              : 150%%;
    }
    p.norm { }
    p.center { text-align      : center; }
    p.i1 { padding-left        : 1em; }
    p.i2 { padding-left        : 2em; }
    p.i3 { padding-left        : 3em; }
    p.i4 { padding-left        : 4em; }
    p.i5 { padding-left        : 5em; }
    p.i6 { padding-left        : 6em; }
    p.i7 { padding-left        : 7em; }
    p.i8 { padding-left        : 8em; }
    p.i9 { padding-left        : 9em; }
    /* hanging indent */
    p[indent="h0i0"] {
      padding-left             : 0em;
      text-indent              : 0em;
    }
    p.publication {
      font-size                : 1.6rem;
      margin-left              : 0em;
      margin-top               : 0px;
      margin-bottom            : 0px;
      margin-right             : 6px;
      text-align               : left;
    }
    p.ocn_is {
      font-size                : 1.6rem;
      display                  : inline-block;
    }
    p.matched_ocn {
      font-size                : 1.5rem;
      margin-left              : 2em;
      margin-top               : 0px;
      margin-bottom            : 0px;
      margin-right             : 6px;
      text-align               : left;
    }
    p[indent="h0i1"] {
      padding-left             : 1em;
      text-indent              : -1em;
    }
    p[indent="h0i2"] {
      padding-left             : 2em;
      text-indent              : -2em;
    }
    p[indent="h0i3"] {
      padding-left             : 3em;
      text-indent              : -3em;
    }
    p[indent="h0i4"] {
      padding-left             : 4em;
      text-indent              : -4em;
    }
    p[indent="h0i5"] {
      padding-left             : 5em;
      text-indent              : -5em;
    }
    p[indent="h0i6"] {
      padding-left             : 6em;
      text-indent              : -6em;
    }
    p[indent="h0i7"] {
      padding-left             : 7em;
      text-indent              : -7em;
    }
    p[indent="h0i8"] {
      padding-left             : 8em;
      text-indent              : -8em;
    }
    p[indent="h0i9"] {
      padding-left             : 9em;
      text-indent              : -9em;
    }
    p[indent="h1i0"] {
      padding-left             : 0em;
      text-indent              : 1em;
    }
    p[indent="h1i1"] {
      padding-left             : 1em;
      text-indent              : 0em;
    }
    p[indent="h1i2"] {
      padding-left             : 2em;
      text-indent              : -1em;
    }
    p[indent="h1i3"] {
      padding-left             : 3em;
      text-indent              : -2em;
    }
    p[indent="h1i4"] {
      padding-left             : 4em;
      text-indent              : -3em;
    }
    p[indent="h1i5"] {
      padding-left             : 5em;
      text-indent              : -4em;
    }
    p[indent="h1i6"] {
      padding-left             : 6em;
      text-indent              : -5em;
    }
    p[indent="h1i7"] {
      padding-left             : 7em;
      text-indent              : -6em;
    }
    p[indent="h1i8"] {
      padding-left             : 8em;
      text-indent              : -7em;
    }
    p[indent="h1i9"] {
      padding-left             : 9em;
      text-indent              : -8em;
    }
    p[indent="h2i0"] {
      padding-left             : 0em;
      text-indent              : 2em;
    }
    p[indent="h2i1"] {
      padding-left             : 1em;
      text-indent              : 1em;
    }
    p[indent="h2i2"] {
      padding-left             : 2em;
      text-indent              : 0em;
    }
    p[indent="h2i3"] {
      padding-left             : 3em;
      text-indent              : -1em;
    }
    p[indent="h2i4"] {
      padding-left             : 4em;
      text-indent              : -2em;
    }
    p[indent="h2i5"] {
      padding-left             : 5em;
      text-indent              : -3em;
    }
    p[indent="h2i6"] {
      padding-left             : 6em;
      text-indent              : -4em;
    }
    p[indent="h2i7"] {
      padding-left             : 7em;
      text-indent              : -5em;
    }
    p[indent="h2i8"] {
      padding-left             : 8em;
      text-indent              : -6em;
    }
    p[indent="h2i9"] {
      padding-left             : 9em;
      text-indent              : -7em;
    }
    p[indent="h3i0"] {
      padding-left             : 0em;
      text-indent              : 3em;
    }
    p[indent="h3i1"] {
      padding-left             : 1em;
      text-indent              : 2em;
    }
    p[indent="h3i2"] {
      padding-left             : 2em;
      text-indent              : 1em;
    }
    p[indent="h3i3"] {
      padding-left             : 3em;
      text-indent              : 0em;
    }
    p[indent="h3i4"] {
      padding-left             : 4em;
      text-indent              : -1em;
    }
    p[indent="h3i5"] {
      padding-left             : 5em;
      text-indent              : -2em;
    }
    p[indent="h3i6"] {
      padding-left             : 6em;
      text-indent              : -3em;
    }
    p[indent="h3i7"] {
      padding-left             : 7em;
      text-indent              : -4em;
    }
    p[indent="h3i8"] {
      padding-left             : 8em;
      text-indent              : -5em;
    }
    p[indent="h3i9"] {
      padding-left             : 9em;
      text-indent              : -6em;
    }
    p[indent="h4i0"] {
      padding-left             : 0em;
      text-indent              : 4em;
    }
    p[indent="h4i1"] {
      padding-left             : 1em;
      text-indent              : 3em;
    }
    p[indent="h4i2"] {
      padding-left             : 2em;
      text-indent              : 2em;
    }
    p[indent="h4i3"] {
      padding-left             : 3em;
      text-indent              : 1em;
    }
    p[indent="h4i4"] {
      padding-left             : 4em;
      text-indent              : 0em;
    }
    p[indent="h4i5"] {
      padding-left             : 5em;
      text-indent              : -1em;
    }
    p[indent="h4i6"] {
      padding-left             : 6em;
      text-indent              : -2em;
    }
    p[indent="h4i7"] {
      padding-left             : 7em;
      text-indent              : -3em;
    }
    p[indent="h4i8"] {
      padding-left             : 8em;
      text-indent              : -4em;
    }
    p[indent="h4i9"] {
      padding-left             : 9em;
      text-indent              : -5em;
    }
    p[indent="h5i0"] {
      padding-left             : 0em;
      text-indent              : 5em;
    }
    p[indent="h5i1"] {
      padding-left             : 1em;
      text-indent              : 4em;
    }
    p[indent="h5i2"] {
      padding-left             : 2em;
      text-indent              : 3em;
    }
    p[indent="h5i3"] {
      padding-left             : 3em;
      text-indent              : 2em;
    }
    p[indent="h5i4"] {
      padding-left             : 4em;
      text-indent              : 1em;
    }
    p[indent="h5i5"] {
      padding-left             : 5em;
      text-indent              : 0em;
    }
    p[indent="h5i6"] {
      padding-left             : 6em;
      text-indent              : -1em;
    }
    p[indent="h5i7"] {
      padding-left             : 7em;
      text-indent              : -2em;
    }
    p[indent="h5i8"] {
      padding-left             : 8em;
      text-indent              : -3em;
    }
    p[indent="h5i9"] {
      padding-left             : 9em;
      text-indent              : -4em;
    }
    p[indent="h6i0"] {
      padding-left             : 0em;
      text-indent              : 6em;
    }
    p[indent="h6i1"] {
      padding-left             : 1em;
      text-indent              : 5em;
    }
    p[indent="h6i2"] {
      padding-left             : 2em;
      text-indent              : 4em;
    }
    p[indent="h6i3"] {
      padding-left             : 3em;
      text-indent              : 3em;
    }
    p[indent="h6i4"] {
      padding-left             : 4em;
      text-indent              : 2em;
    }
    p[indent="h6i5"] {
      padding-left             : 5em;
      text-indent              : 1em;
    }
    p[indent="h6i6"] {
      padding-left             : 6em;
      text-indent              : 0em;
    }
    p[indent="h6i7"] {
      padding-left             : 7em;
      text-indent              : -1em;
    }
    p[indent="h6i8"] {
      padding-left             : 8em;
      text-indent              : -2em;
    }
    p[indent="h6i9"] {
      padding-left             : 9em;
      text-indent              : -3em;
    }
    p[indent="h7i0"] {
      padding-left             : 0em;
      text-indent              : 7em;
    }
    p[indent="h7i1"] {
      padding-left             : 1em;
      text-indent              : 6em;
    }
    p[indent="h7i2"] {
      padding-left             : 2em;
      text-indent              : 5em;
    }
    p[indent="h7i3"] {
      padding-left             : 3em;
      text-indent              : 4em;
    }
    p[indent="h7i4"] {
      padding-left             : 4em;
      text-indent              : 3em;
    }
    p[indent="h7i5"] {
      padding-left             : 5em;
      text-indent              : 2em;
    }
    p[indent="h7i6"] {
      padding-left             : 6em;
      text-indent              : 1em;
    }
    p[indent="h7i7"] {
      padding-left             : 7em;
      text-indent              : 0em;
    }
    p[indent="h7i8"] {
      padding-left             : 8em;
      text-indent              : -1em;
    }
    p[indent="h7i9"] {
      padding-left             : 9em;
      text-indent              : -2em;
    }
    p[indent="h8i0"] {
      padding-left             : 0em;
      text-indent              : 8em;
    }
    p[indent="h8i1"] {
      padding-left             : 1em;
      text-indent              : 7em;
    }
    p[indent="h8i2"] {
      padding-left             : 2em;
      text-indent              : 6em;
    }
    p[indent="h8i3"] {
      padding-left             : 3em;
      text-indent              : 5em;
    }
    p[indent="h8i4"] {
      padding-left             : 4em;
      text-indent              : 4em;
    }
    p[indent="h8i5"] {
      padding-left             : 5em;
      text-indent              : 3em;
    }
    p[indent="h8i6"] {
      padding-left             : 6em;
      text-indent              : 2em;
    }
    p[indent="h8i7"] {
      padding-left             : 7em;
      text-indent              : 1em;
    }
    p[indent="h8i8"] {
      padding-left             : 8em;
      text-indent              : 0em;
    }
    p[indent="h8i9"] {
      padding-left             : 9em;
      text-indent              : -1em;
    }
    p[indent="h9i0"] {
      padding-left             : 0em;
      text-indent              : 9em;
    }
    p[indent="h9i1"] {
      padding-left             : 1em;
      text-indent              : 8em;
    }
    p[indent="h9i2"] {
      padding-left             : 2em;
      text-indent              : 7em;
    }
    p[indent="h9i3"] {
      padding-left             : 3em;
      text-indent              : 6em;
    }
    p[indent="h9i4"] {
      padding-left             : 4em;
      text-indent              : 5em;
    }
    p[indent="h9i5"] {
      padding-left             : 5em;
      text-indent              : 4em;
    }
    p[indent="h9i6"] {
      padding-left             : 6em;
      text-indent              : 3em;
    }
    p[indent="h9i7"] {
      padding-left             : 7em;
      text-indent              : 2em;
    }
    p[indent="h9i8"] {
      padding-left             : 8em;
      text-indent              : 1em;
    }
    p[indent="h9i9"] {
      padding-left             : 9em;
      text-indent              : 0em;
    }
    p.spaced { white-space     : pre; }
    p.block {
      white-space              : pre;
    }
    p.group { }
    p.alt { }
    p.verse {
      white-space              : pre;
      margin-bottom            : 6px;
    }
    p.caption {
      text-align               : left;
      font-size                : 80%%;
      display                  : inline;
    }
    p.endnote {
      font-size                : 1.5rem;
      line-height              : 120%%;
      text-align               : left;
      margin-right             : 15mm;
      padding-left             : 1em;
      text-indent              : -1em;
    }
    p.center {
      text-align               : center;
    }
    p.bold {
      font-weight              : bold;
    }
    p.bold_left {
      font-weight              : bold;
      text-align               : left;
    }
    p.centerbold {
      text-align               : center;
      font-weight              : bold;
    }
    p.em {
      font-weight              : bold;
      font-style               : normal;
      background               : #FFF3B6;
    }
    p.small {
      font-size                : 1.4rem;
      margin-top               : 0px;
      margin-bottom            : 0px;
      margin-right             : 6px;
      text-align               : left;
    }
    .tiny, .tiny_left, .tiny_right, .tiny_center {
      font-size                : 1.3rem;
      margin-top               : 0px;
      margin-bottom            : 0px;
      color                    : #EEEEEE;
      margin-right             : 6px;
      text-align               : left;
    }
    p.tiny { }
    p.tiny_left {
      margin-left              : 0px;
      margin-right             : 0px;
      text-align               : left;
    }
    p.tiny_right {
      margin-right             : 1em;
      text-align               : right;
    }
    p.tiny_center {
      margin-left              : 0px;
      margin-right             : 0px;
      text-align               : center;
    }
    p.book_index_lev1 {
      line-height              : 100%%;
      margin-top               : 4px;
      margin-bottom            : 1px;
    }
    p.book_index_lev2 {
      line-height              : 100%%;
      text-align               : left;
      margin-left              : 3em;
      margin-top               : 1px;
      margin-bottom            : 3px;
    }
    tt {
      font-family              : inconsolata, "liberation mono", "bitstream vera mono", "dejavu mono", monaco, consolas, "andale mono", "courier new", "courier 10 pitch", courier, monospace;
      background-color         : #555555;
      color                    : #DDDDDD;
    }
    pre {
      width                    : auto;
      display                  : block;
      clear                    : both;
      color                    : #555555;
    }
    pre.codeline {
      display                  : table;
      clear                    : both;
      table-layout             : fixed;
      margin-left              : 5%%;
      margin-right             : 5%%;
      width                    : 90%%;
      white-space              : pre-wrap;
      border-style             : none;
      border-radius            : 5px 5px 5px 5px;
      box-shadow               : 0 2px 5px #AAAAAA inset;
      margin-bottom            : 1em;
      padding                  : 0.5em 1em;
      page-break-inside        : avoid;
      word-wrap                : break-word;
      font-family              : inconsolata, "liberation mono", "bitstream vera mono", "dejavu mono", monaco, consolas, "andale mono", "courier new", "courier 10 pitch", courier, monospace;
      white-space              : pre;
      white-space              : pre-wrap;
      white-space              : -moz-pre-wrap;
      white-space              : -o-pre-wrap;
      background-color         : #555555;
      color                    : #DDDDDD;
      font-size                : 1.8rem;
      line-height              : 120%%;
    }
    pre.codeline::before {
      counter-reset            : linenum;
    }
    pre.codeline span.tr {
      display                  : table-row;
      counter-increment        : linenum;
    }
    pre.codeline span.th {
      display                  : table-cell;
      user-select              : none;
      -moz-user-select         : none;
      -webkit-user-select      : none;
      padding                  : 0.5em 0.5em;
    }
    pre.codeline span.th::before {
      content                  : counter(linenum) ".";
      color                    : #999999;
      text-align               : right;
      display                  : block;
    }
    pre.codeline span.th {
      width                    : 4em;
    }
    pre.codeline code {
      display                  : table-cell;
    }
    p.code {
      border-style             : none;
    }
    note { white-space         : pre; }
    em {
      font-weight              : bold;
      font-style               : italic;
    }
    p.left,th.left,td.left {
      text-align               : left;
    }
    p.small_left,th.small_left,td.small_left {
      text-align               : left;
      font-size                : 1.4rem;
    }
    p.right,th.right,td.right {
      text-align               : right;
    }
    ul, li {
      list-style-type          : none;
      list-style               : none;
      padding-left             : 20px;
      font-weight              : normal;
      line-height              : 150%%;
      text-align               : left;
      text-indent              : 0mm;
      margin-left              : 1em;
      margin-right             : 2em;
      margin-top               : 3px;
      margin-bottom            : 3px;
    }
    li {
      background               : (../image_sys/bullet_09.png) no-repeat 0px 6px;
    }
    ul { }
    h0, h1, h2, h3, h4, h5, h6, h7 {
      font-weight              : bold;
      line-height              : 120%%;
      text-align               : left;
      margin-top               : 20px;
      margin-bottom            : 10px;
    }
    h4.norm, h5.norm, h6.norm, h7.norm {
      margin-top               : 10px;
      margin-bottom            : 0px;
    }
    h0 { font-size             : 2rem; }
    h1 { font-size             : 1.9rem; }
    h2 { font-size             : 1.8rem; }
    h3 { font-size             : 1.7rem; }
    h4 { font-size             : 1.6rem; }
    h5 { font-size             : 1.6rem; }
    h6 { font-size             : 1.6rem; }
    h7 { font-size             : 1.6rem; }
    h0, h1, h2, h3, h4, h5, h6, h7 {
      text-shadow              : .2em .2em .3em #999999;
    }
    h1.i { margin-left         : 2em; }
    h2.i { margin-left         : 3em; }
    h3.i { margin-left         : 4em; }
    h4.i { margin-left         : 5em; }
    h5.i { margin-left         : 6em; }
    h6.i { margin-left         : 7em; }
    h7.i { margin-left         : 8em; }
    h8.i { margin-left         : 9em; }
    h9.i { margin-left         : 10em; }
    .toc {
      font-weight              : normal;
      margin-top               : 6px;
      margin-bottom            : 6px;
    }
    h0.toc {
      margin-left              : 1em;
      font-size                : 2rem;
      line-height              : 150%%;
    }
    h1.toc {
      margin-left              : 1em;
      font-size                : 1.9rem;
      line-height              : 150%%;
    }
    h2.toc {
      margin-left              : 2em;
      font-size                : 1.8rem;
      line-height              : 140%%;
    }
    h3.toc {
      margin-left              : 3em;
      font-size                : 1.7rem;
      line-height              : 120%%;
    }
    h4.toc {
      margin-left              : 4em;
      font-size                : 1.6rem;
      line-height              : 120%%;
    }
    h5.toc {
      margin-left              : 5em;
      font-size                : 1.5rem;
      line-height              : 110%%;
    }
    h6.toc {
      margin-left              : 6em;
      font-size                : 1.4rem;
      line-height              : 110%%;
    }
    h7.toc {
      margin-left              : 7em;
      font-size                : 1.3rem;
      line-height              : 100%%;
    }
    .subtoc {
      margin-right             : 34%%;
      font-weight              : normal;
    }
    h5.subtoc {
      margin-left              : 2em;
      font-size                : 1.5rem;
      margin-top               : 2px;
      margin-bottom            : 2px;
    }
    h6.subtoc {
      margin-left              : 3em;
      font-size                : 1.4rem;
      margin-top               : 0px;
      margin-bottom            : 0px;
    }
    h7.subtoc {
      margin-left              : 4em;
      font-size                : 1.3rem;
      margin-top               : 0px;
      margin-bottom            : 0px;
    }
    hr {
      display                  : block;
      height                   : 1px;
      width                    : 100%%;
      border                   : 0;
      border-top               : 1px solid #AAAAAA;
      border-color             : #AAAAAA
      background-color         : #AAAAAA
      margin-left              : 0%%;
      margin-right             : 0em;
      margin-top               : 0.5em;
      margin-bottom            : 0.5em;
      padding                  : 0;
    }
  </style>
</head>
<body lang="en" xml:lang="en">
┃",
    conf.cgi_search_form_title,
    conf.http_request_type,
    conf.http_host,
   );
  }
  {
    table = format(q"┃
  <table summary="band" border="0" cellpadding="2" cellspacing="0">
  <tr><td width="20%%">
   <table summary="home button / home information" border="0" cellpadding="2" cellspacing="0">
   <tr><td align="left">
     %s
   </td></tr>
   </table>
  </td>
  <td>
  </td></tr>
  </table>
    ┃",
      conf.cgi_search_form_html_title,
    );
  }
  {
    string post_value(string field_name, string type="box", string set="on") {
      string val = "";
      switch (type) {
      case "field":
        val = ((field_name in cgi.post && !(cgi.post[field_name]).empty)
          ? cgi.post[field_name]
          : (field_name in cgi.get)
            ? cgi.get[field_name]
            : "");
        val = tf.search_text_area;
        break;
      case "box": // generic for checkbox or radio; checkbox set == "on" radio set == "name set"
        val = ((field_name in cgi.post && !(cgi.post[field_name]).empty)
          ? (cgi.post[field_name]  == set ? "checked" : "off")
          : (field_name in cgi.get)
            ? (cgi.get[field_name] == set ? "checked" : "off")
            :                               "off");
        break;
      case "radio": // used generic bo
        val = ((field_name in cgi.post && !(cgi.post[field_name]).empty)
          ? (cgi.post[field_name]  == set ? "checked" : "off")
          : (field_name in cgi.get)
            ? (cgi.get[field_name] == set ? "checked" : "off")
            :                               "checked");
        break;
      case "checkbox": // used generic bo
        val = ((field_name in cgi.post && !(cgi.post[field_name]).empty)
          ? (cgi.post[field_name]  == set ? "checked" : "off")
          : (field_name in cgi.get)
            ? (cgi.get[field_name] == set ? "checked" : "off")
            :                               "checked");
        break;
      default:
      }
      return val;
    }
    string the_can(string fv) {
      string show_the_can = post_value("url");
      string _the_can = "";
      if (show_the_can == "checked") {
        tf = text_fields;
        string method_get_url            = conf.query_base_url ~ environment.get("QUERY_STRING", "");
        string method_post_url_construct = conf.query_base_url ~ tf.canned_query;
        // assert(method_get_url == environment.get("HTTP_REFERER", conf.query_base_url ~ conf.query_string));
        if (conf.request_method == "POST") {
          _the_can =
            "<font-size=\"1rem\" color=\"#666666\">"
            ~ "POST:&nbsp;"
            ~ "<a href=\""
            ~ method_post_url_construct
            ~ "\">"
            ~ method_post_url_construct
            ~ "</a></font>"
            ~ "<br>";
        } else if (conf.request_method == "GET") {
          _the_can =
            "<font-size=\"1rem\" color=\"#666666\">"
            ~ "GET:&nbsp;&nbsp;"
            ~ "<a href=\""
            ~ method_get_url
            ~ "\">"
            ~ method_get_url
            ~ "</a></font>";
        }
        conf.http_url = conf.http_request_type ~ "://" ~ conf.http_host ~ conf.cgi_script_name ~ tf.canned_query;
      }
      return _the_can;
    }
    string provide_tip() {
      string searched_tip = post_value("se");
      string tip = "";
      if (searched_tip == "checked") {
        string search_field = post_value("sf", "field");
        tf = text_fields;
        tip = format(q"┃
      <font-size="1rem" color="#666666">
      <b>database:</b> <font-size="1rem" color="#004000">%s</font>; <b>selected view:</b> <font-size="2" color="#004000">index</font>
      <b>search string:</b> %s %s %s %s %s %s<br>
      %s %s %s %s %s %s
      </font>
      ┃",
          cv.db_selected,
          (tf.text.empty   ? "" : "\"text:   <font-size=\"1rem\" color=\"#004000\">" ~ tf.text   ~ "</font>; "),
          (tf.title.empty  ? "" : "\"title:  <font-size=\"1rem\" color=\"#004000\">" ~ tf.title  ~ "</font>; "),
          (tf.author.empty ? "" : "\"author: <font-size=\"1rem\" color=\"#004000\">" ~ tf.author ~ "</font>; "),
          (tf.date.empty   ? "" : "\"date    <font-size=\"1rem\" color=\"#004000\">" ~ tf.date   ~ "</font>; "),
          (tf.uid.empty    ? "" : "\"uid:    <font-size=\"1rem\" color=\"#004000\">" ~ tf.uid    ~ "</font>; "),
          (tf.fn.empty     ? "" : "\"fn:     <font-size=\"1rem\" color=\"#004000\">" ~ tf.fn     ~ "</font>; "),
          (tf.text.empty   ? "" :  "text:    <font-size=\"1rem\" color=\"#004000\">" ~ tf.text   ~ "</font><br>"),
          (tf.title.empty  ? "" : "title:    <font-size=\"1rem\" color=\"#004000\">" ~ tf.title  ~ "</font><br>"),
          (tf.author.empty ? "" :  "author:  <font-size=\"1rem\" color=\"#004000\">" ~ tf.author ~ "</font><br>"),
          (tf.date.empty   ? "" :  "date:    <font-size=\"1rem\" color=\"#004000\">" ~ tf.date   ~ "</font><br>"),
          (tf.uid.empty    ? "" : "\"uid:    <font-size=\"1rem\" color=\"#004000\">" ~ tf.uid    ~ "</font>; "),
          (tf.fn.empty     ? "" : "\"fn:     <font-size=\"1rem\" color=\"#004000\">" ~ tf.fn     ~ "</font>; "),
        );
      }
      return tip;
    }
    form = format(q"┃
<form action="%s" id="SubmitForm" method="post" accept-charset="UTF-8">
  <table cellpadding="2">
  <tr><td valign=\"top\">
      <textarea id="find" name="sf" type="text" rows="6" cols="40" maxlength="256" wrap="virtual">%s</textarea>
  </td>
  <td valign=\"top\">
    %s
    %s
    %s
  </td></tr></table>
  <td valign=\"top\"><tr><td>
    <font-size="1rem" color="#222222">
    <input type="hidden" name="db" value="%s">
    <input type="submit" value="፨ SiSU search ❭❭">
    match [ results:
    <input type="radio" name="rt" id="results_type_index" value="idx" %s> ፨ (index)
    <input type="radio" name="rt" id="results_type_text" value="txt" %s> ⚏ (text / grep)
    ]&nbsp;&nbsp;[ limit:
    <input type="radio" name="sml" id="sql_match_limit_1000" value="1000" %s> 1,000
    <input type="radio" name="sml" id="sql_match_limit_2500" value="2500" %s> 2,500
    ]
    <br>
      <input type="checkbox" name="ec" %s> echo query
      <input type="checkbox" name="url" %s> search url
      <input type="checkbox" name="se" %s> searched
      <input type="checkbox" name="sql" %s> sql statement
      <input type="hidden" name="smo" value="0">
    <br>
    </font>
  </td></tr>
  </table>
</form>
┃",
      _cfg.cgi_filename,
      (post_value("ec") == "checked") ? post_value("sf", "field") : "",
      provide_tip,
      search_note,
      the_can(post_value("sf", "field")),
      cv.db_selected,
      post_value("rt",  "box", "idx"),
      post_value("rt",  "box", "txt"),
      post_value("sml", "box", "1000"),
      post_value("sml", "box", "2500"),
      post_value("ec"),
      post_value("url"),
      post_value("se"),
      post_value("sql"),
    );
    {
      string set_value(string field_name, string default_val) {
        string val;
        if (field_name in cgi.post) {
          val = cgi.post[field_name];
        } else if (field_name in cgi.get) {
          val = cgi.get[field_name];
        } else { val = default_val; }
        return val;
      }
      bool set_bool(string field_name) {
        bool val;
        if (field_name in cgi.post
        && cgi.post[field_name] == "on") {
          val = true;
        } else if (field_name in cgi.get
        && cgi.get[field_name] == "on") {
          val = true;
        } else { val = false; }
        return val;
      }
      cv.db_selected      = set_value("selected_db", _cfg.db_sqlite_filename); // selected_db_name == db (spine.search.db or whatever)
      cv.sql_match_limit  = set_value("sml",         "1000");
      cv.sql_match_offset = set_value("smo",         "0");
      cv.search_text      = set_value("sf",          "");
      cv.results_type     = set_value("rt",          "idx");
      cv.checked_echo     = set_bool("ec");
      cv.checked_stats    = set_bool("sts");
      cv.checked_url      = set_bool("url");
      cv.checked_searched = set_bool("se");
      cv.checked_tip      = set_bool("tip");
      cv.checked_sql      = set_bool("sql");
      tf = text_fields;
    }
  }
  {
    cgi.write(header);
    cgi.write(table);
    cgi.write(form);
    // cgi.write(previous_next);
    { // debug environment
      // foreach (k, d; environment.toAA) {
      //   cgi.write(k ~ ": " ~ d ~ "<br>");
      // }
    }
    { // debug cgi info:
      // cgi.write("db with path: "        ~ conf.db_path ~ "/" ~ cv.db_selected ~ "<br>\n");
      // cgi.write("http url: "            ~ conf.http_url ~ "<br>\n");
      // cgi.write("query base url: "      ~ conf.query_base_url ~ "<br>\n");
      // cgi.write("db_selected: "         ~ cv.db_selected ~ "<br>\n");
      // cgi.write("search_text: "         ~ cv.search_text ~ "<br>\n");
      // cgi.write("sql_match_limit: "     ~ cv.sql_match_limit ~ ";\n");
      // cgi.write("sql_match_offset: "    ~ cv.sql_match_offset ~ ";\n");
      // cgi.write("results_type: "        ~ cv.results_type ~ "<br>\n");
      // cgi.write("cv.checked_echo: "     ~ (cv.checked_echo ? "checked" : "off") ~ "; \n");
      // cgi.write("cv.checked_stats: "    ~ (cv.checked_stats ? "checked" : "off") ~ "; \n");
      // cgi.write("cv.checked_url: "      ~ (cv.checked_url ? "checked" : "off") ~ "; \n");
      // cgi.write("cv.checked_searched: " ~ (cv.checked_searched ? "checked" : "off") ~ ";<br>\n");
      // cgi.write("cv.checked_tip: "      ~ (cv.checked_tip ? "checked" : "off") ~ "; \n");
      // cgi.write("cv.checked_sql: "      ~ (cv.checked_sql ? "checked" : "off") ~ "<br>\n");
    }
  }
  auto db = Database(conf.db_path ~ "/" ~ cv.db_selected);
  {
    uint sql_match_offset_counter(T)(T cv) {
      sql_match_offset_count += cv.sql_match_limit.to!uint;
      return sql_match_offset_count;
    }
    void sql_search_query() {
      string highlight_text_matched(string _txt, string search_field) {
        string _mark_open   = "┤";
        string _mark_close  = "├";
        string _span_match = "<span class=\"match\">";
        string _span_close  = "</span>";
        string _sf_str      = search_field.strip.split("%20").join(" ").strip;
        string[] _sf_arr    = _sf_str.split(regex(r"\s+AND\s+|\s+OR\s+"));
        auto rgx_url        = regex(r"<a href=[^>]+?>");
        foreach (_sf; _sf_arr) {
          auto rgx_matched_text = regex(_sf, "i");
          auto rgx_marked_pair  = regex(r"┤(?P<keep>" ~ _sf ~ ")├", "i");
          if (auto m = _txt.matchFirst(rgx_url)) {
            _txt = replaceAll!(m =>
                _mark_open
                ~  m.captures[0]
                ~ _mark_close
              )(_txt, rgx_matched_text);
            _txt = replaceAll!(m =>
                replaceAll!(u =>
                  u["keep"]
                )(m.hit, rgx_marked_pair)
              )(_txt, rgx_url);
            _txt = replaceAll!(m =>
                _span_match
                ~  m["keep"]
                ~ _span_close
              )(_txt, rgx_marked_pair);
          } else {
            _txt = replaceAll!(m =>
                _span_match
                ~  m.captures[0]
                ~ _span_close
              )(_txt, rgx_matched_text);
          }
        }
        return _txt;
      }
      string select_field_like(string db_field, string search_field) {
        string where_ = "";
        if (!(search_field.empty)) {
          string _sf = search_field.strip.split("%20").join(" ");
          if (_sf.match(r" OR ")) {
            _sf = _sf.split(" OR ").join("%' OR " ~ db_field ~ " LIKE '%");
          }
          if (_sf.match(r" AND ")) {
            _sf = _sf.split(" AND ").join("%' AND " ~ db_field ~ " LIKE '%");
          }
          _sf = "( " ~ db_field ~ " LIKE\n  '%" ~ _sf ~ "%' )";
          where_ ~= format(q"┃
          %s
        ┃",
            _sf
          );
        }
        return where_;
      }
      string[] _fields;
      _fields ~= select_field_like("doc_objects.clean",                         tf.text);
      _fields ~= select_field_like("metadata_and_text.title",                   tf.title);
      _fields ~= select_field_like("metadata_and_text.creator_author",          tf.author);
      _fields ~= select_field_like("metadata_and_text.uid",                     tf.uid);
      _fields ~= select_field_like("metadata_and_text.src_filename_base",       tf.fn);
      _fields ~= select_field_like("metadata_and_text.src_filename_base",       tf.src_filename_base);
      _fields ~= select_field_like("metadata_and_text.language_document_char",  tf.language);
      _fields ~= select_field_like("metadata_and_text.date_published",          tf.date);
      _fields ~= select_field_like("metadata_and_text.classify_keywords",       tf.keywords);
      _fields ~= select_field_like("metadata_and_text.classify_topic_register", tf.topic_register);
      string[] fields;
      foreach (f; _fields) {
        if (!(f.empty)) { fields ~= f; }
      }
      string fields_str = "";
      fields_str ~= fields.join(" AND ");
      sql_select.the_body ~= format(q"┃
SELECT
  metadata_and_text.uid,
  metadata_and_text.title,
  metadata_and_text.creator_author_last_first,
  metadata_and_text.creator_author,
  metadata_and_text.src_filename_base,
  metadata_and_text.language_document_char,
  metadata_and_text.date_published,
  metadata_and_text.classify_keywords,
  metadata_and_text.classify_topic_register,
  doc_objects.body,
  doc_objects.seg_name,
  doc_objects.ocn,
  doc_objects.lev,
  doc_objects.is_a,
  metadata_and_text.uid
FROM
  doc_objects,
  metadata_and_text
WHERE (
  %s
  )
AND
  doc_objects.uid_metadata_and_text = metadata_and_text.uid
ORDER BY
  metadata_and_text.creator_author_last_first,
  metadata_and_text.date_published DESC,
  metadata_and_text.title,
  metadata_and_text.language_document_char,
  metadata_and_text.src_filename_base,
  doc_objects.ocn
LIMIT %s OFFSET %s
;┃",
        fields_str,
        cv.sql_match_limit,
        cv.sql_match_offset,
      );
      (cv.checked_sql)
      ? cgi.write(previous_next
          ~ "<hr><font-size=\"1rem\" color=\"#666666\">"
          ~ sql_select.the_body.strip.split("\n  ").join(" ").split("\n").join("<br>")
          ~ "</font>\n"
        )
      : "";
      cgi.write(previous_next);
      auto select_query_results = db.execute(sql_select.the_body).cached;
      string _old_uid = "";
      if (!select_query_results.empty) {
        string _date_published = "0000";
        string _close_para = "";
        string _matched_ocn_open = "";
        foreach (idx, row; select_query_results) {
          if (row["uid"].as!string != _old_uid) {
            _close_para = (idx == 1) ? "" : "</p>";
            _matched_ocn_open = (idx == 1) ? "" : "<p class=\"matched_ocn\">";
            _old_uid = row["uid"].as!string;
            _date_published = (row["date_published"].as!string.match(regex(r"^([0-9]{4})")))
            ? row["date_published"].as!string : "0000"; // used in regex that breaks if no match
            auto m = _date_published.match(regex(r"^([0-9]{4})"));
            string _date = (m.hit == "0000") ? "(year?) " : "(" ~ m.hit ~ ") ";
            cgi.write(
              _close_para
              ~ "<hr><div class=\"publication\">"
                ~ "<p class=\"publication\"><a href=\""
                  ~ conf.http_request_type ~ "://"
                  ~ conf.http_host ~ conf.doc_collection_subroot ~ "/"
                  ~ row["language_document_char"].as!string ~ "/html/"
                  ~ row["src_filename_base"].as!string ~ "/"
                  ~ "toc.html"
                ~ "\">\""
                  ~ row["title"].as!string ~ "\""
                ~ "</a> "
                ~ _date
                ~ "[" ~ row["language_document_char"].as!string ~ "] "
                ~ row["creator_author_last_first"].as!string
                ~ " "
                ~ show_matched_objects(row["src_filename_base"].as!string)
                ~ "</p>"
              ~ "</div>"
            );
          }
          if (cv.results_type == "txt") {
            string _sfn, _id;
            if ((row["lev"].as!int < 4)
            || (row["ocn"].as!string == "0")) {
              if (row["is_a"].as!string == "bookindex") {
                _sfn = "bookindex";
                _id = "idx";
              } else if (row["is_a"].as!string == "blurb") {
                _sfn = "blurb";
                _id = "bm";
              } else {
                _sfn = "toc";
                _id = row["ocn"].as!string;
              }
              cgi.write(
                "<div class=\"flex-container\">"
                ~ "<div class=\"textview_ocn\" style=\"flex: 0 0 1.2em\">"
                  ~ "<p class=\"ocn_is\"><a href=\""
                    ~ conf.http_request_type ~ "://"
                    ~ conf.http_host ~ conf.doc_collection_subroot ~ "/"
                    ~ row["language_document_char"].as!string ~ "/html/"
                    ~ row["src_filename_base"].as!string ~ "/"
                    ~ _sfn ~ ".html"
                  ~ "\">"
                    ~ _id
                  ~ "</a>:</p>"
                ~ "</div>"
                ~ "<div class=\"textview_found\">"
                  ~ highlight_text_matched(row["body"].as!string, tf.text)
                ~ "</div>"
                ~ "</div>"
              );
            } else {
              if (row["is_a"].as!string == "bibliography") {
                _id = row["ocn"].as!string ~ "b";
                _sfn = "bibliography";
              } else if (row["is_a"].as!string == "glossary") {
                _id = row["ocn"].as!string ~ "g";
                _sfn = "glossary";
              } else {
                _id = row["ocn"].as!string;
                _sfn = row["seg_name"].as!string;
              }
              cgi.write(
                "<div class=\"flex-container\">"
                ~ "<div class=\"textview_ocn\" style=\"flex: 0 0 1.2em\">"
                  ~ "<p class=\"ocn_is\"><a href=\""
                    ~ conf.http_request_type ~ "://"
                    ~ conf.http_host ~ conf.doc_collection_subroot ~ "/"
                    ~ row["language_document_char"].as!string ~ "/html/"
                    ~ row["src_filename_base"].as!string ~ "/"
                    ~ _sfn ~ ".html#" ~ row["ocn"].as!string
                  ~ "\">"
                    ~  _id
                  ~ "</a>:</p>"
                ~ "</div>"
                ~ "<div class=\"textview_found\">"
                  ~ highlight_text_matched(row["body"].as!string, tf.text)
                ~ "</div>"
                ~ "</div>"
              );
            }
          } else {
            string _sfn, _id;
            if ((row["lev"].as!int < 4)
            || (row["ocn"].as!string == "0")) {
              if (row["is_a"].as!string == "bookindex") {
                _sfn = "bookindex";
                _id = "i";
              } else if (row["is_a"].as!string == "blurb") {
                _sfn = "blurb";
                _id = "bm";
              } else {
                _sfn = "toc";
                _id = row["ocn"].as!string;
              }
              cgi.write(
                _matched_ocn_open
                ~ "<a href=\""
                  ~ conf.http_request_type ~ "://"
                  ~ conf.http_host ~ conf.doc_collection_subroot ~ "/"
                  ~ row["language_document_char"].as!string ~ "/html/"
                  ~ row["src_filename_base"].as!string ~ "/"
                  ~ _sfn ~ ".html"
                ~ "\">"
                  ~ _id
                ~ "</a>, "
              );
            } else {
              if (row["is_a"].as!string == "bibliography") {
                _id = row["ocn"].as!string ~ "b";
                _sfn = "bibliography";
              } else if (row["is_a"].as!string == "glossary") {
                _id = row["ocn"].as!string ~ "g";
                _sfn = "glossary";
              } else {
                _id = row["ocn"].as!string;
                _sfn = row["seg_name"].as!string;
              }
              cgi.write(
                _matched_ocn_open
                ~ "<a href=\""
                  ~ conf.http_request_type ~ "://"
                  ~ conf.http_host ~ conf.doc_collection_subroot ~ "/"
                  ~ row["language_document_char"].as!string ~ "/html/"
                  ~ row["src_filename_base"].as!string ~ "/"
                  ~ _sfn ~ ".html#" ~ row["ocn"].as!string
                ~ "\">"
                  ~  _id
                ~ "</a>, "
              );
            }
            _matched_ocn_open = "";
          }
        }
        cgi.write( previous_next);
      } else { // offset_not_beyond_limit = false;
        cgi.write("select_query_results empty<p>\n");
      }
      cgi.write("<br><p class=\"center\">
<label for=\"find\">
<a href=\"https://sisudoc.org/\" target=\"_top\"><b>≅ SiSU Spine ፨</b></a>
</label>
<label for=\"find\">(object numbering &amp; object search)</label>
<label for=\"find\">2023</label>
<br><label for=\"find\">(web 1993, object numbering 1997, object search 2002 ...)</label>
<br><a href=\"https://git.sisudoc.org/\" target=\"_top\">Δ git</a>
</p>
");
    }
    sql_search_query;
  }
  {
    db.close;
  }
  {
    string tail = format(q"┃
</body>
┃");
    cgi.write(tail);
  }
}
mixin GenericMain!cgi_function_intro;