/+ 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) {
  string header;
  string table;
  string form;
  struct Config {
    string http_request_type;
    string http_host;
    // string server_name;
    string doc_root;
    string cgi_root;
    string cgi_script;
    string data_path_html;
    string db_path;
    string query_string;
    string http_url;
    string request_method;
  }
  auto conf = Config();
  conf.http_request_type    = environment.get("REQUEST_SCHEME",        "http");
  conf.http_host            = environment.get("HTTP_HOST",             "localhost");
  // conf.server_name          = environment.get("SERVER_NAME",           "localhost");
  conf.doc_root             = environment.get("DOCUMENT_ROOT",         "/var/www/html");
  conf.cgi_root             = environment.get("CONTEXT_DOCUMENT_ROOT", "/usr/lib/cgi-bin/");
  // conf.cgi_script           = environment.get("SCRIPT_NAME",           "/cgi-bin/spine-search");
  conf.query_string         = environment.get("QUERY_STRING",          "");
  conf.http_url             = environment.get("HTTP_REFERER",          conf.http_request_type ~ "://" ~ conf.http_host ~ conf.cgi_script ~ "?" ~ conf.query_string);
  conf.db_path              = "/var/www/html/sqlite/";                 // conf.http_host ~ "/sqlite/";
  conf.request_method       = environment.get("REQUEST_METHOD",        "POST");
  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 = "spine.search.db"; // config, set db name
  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 identifier        = ctRegex!(`(?:^|\s~\s*)identifier:\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");
    }
    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 identifier        = ""; // identifier        == id
      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 rgx  = Rgx();
    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"];
        }
        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.identifier)) {
          got.identifier = m["matched"];
          got.canned_query ~= "&id=" ~ 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 ("id" in canned_query && !(canned_query["id"]).empty) {
        got.identifier = canned_query["id"].split("%20").join(" ");
        got.search_text_area ~= "identifier: " ~ got.identifier ~ "\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 base                  ; // = "";
  string tip                   ; // = "";
  string search_note           ; // = "";
  uint   sql_match_offset_count   = 0;
  string previous_next () {
    static struct Rgx {
      static track_offset = ctRegex!(`(?P<offset_key>[&]smo=)(?P<offset_val>[0-9]+)`, "m");
    }
    auto rgx = Rgx();
    string _previous_next = "";
    int    _current_offset_value = 0;
    string _set_offset_next = "";
    string _set_offset_previous = "";
    string _url = "";
    string _url_previous = "";
    string _url_next = "";
    string arrow_previous = "";
    string arrow_next = "";
    if (environment.get("REQUEST_METHOD", "POST") == "POST") {
      _url = conf.http_request_type ~ "://" ~ conf.http_host ~ conf.cgi_script ~ "?" ~ tf.canned_query;
    } else if (environment.get("REQUEST_METHOD", "POST") == "GET") {
      _url = conf.http_request_type ~ "://" ~ conf.http_host ~ conf.cgi_script ~ "?" ~ environment.get("QUERY_STRING", "");
    }
    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=\"2\" color=\"#666666\">"
        ~ "<a href=\""
        ~ _url_previous
        ~ "\">"
        ~ "&lt;&lt prev"
        ~ "</a> || </font>";
    }
    arrow_next =
      "<font size=\"2\" color=\"#666666\">"
      ~ "<a href=\""
      ~ _url_next
      ~ "\">"
      ~ "next &gt;&gt"
      ~ "</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>
    SiSU spine search form (sample)
  </title>
  <meta name="sourcefile" content="SiSU.sst" />
  <link rel="generator" href="sisudoc.org" />
  <link rel="shortcut icon" href="http://%s/image_sys/spine.ico" />
  <style media = "all">
   *{
    padding                  : 0px;
    margin                   : 2px;
  }
  body {
    height                   : 100vh;
    background-color         : #FFFFFF;
  }
  body {
    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.lnkocn:link {
    color                    : #777777;
    text-decoration          : none;
  }
  a.lnkocn:visited {
    color                    : #32CD32;
    text-decoration          : none;
  }
  a.lnkocn:hover {
    color                    : #777777;
    font-size                : 15px;
  }
  a:hover img {
    background-color         : #FFFFFF;
  }
  a:active {
    color                    : #003399;
    text-decoration          : underline;
  }
  hr {
    width                    : 100%%;
    margin-left              : 0%%;
    margin-right             : 0em;
    margin-top               : 0.5em;
    margin-bottom            : 0.5em;
  }
</style>
</head>
<body lang="en" xml:lang="en">
┃",
    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">
   <br /><a href="http://sisudoc.org/" target="_top">
     <b>SiSU</b>
   </a>
   <br /><a href="http://git.sisudoc.org/" target="_top">
     git
   </a>
  </td></tr>
  </table>
 </td>
 <td>
   <label for="find"><b>SiSU spine (generated) search form</b></label>
 </td></tr>
 </table>
 ┃");
  }
  {
    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.http_request_type ~ "://" ~ conf.http_host ~ conf.cgi_script ~ "?" ~ environment.get("QUERY_STRING", "");
        string method_post_url_construct = conf.http_request_type ~ "://" ~ conf.http_host ~ conf.cgi_script ~ "?" ~ tf.canned_query;
        // assert(method_get_url == environment.get("HTTP_REFERER", conf.http_request_type ~ "://" ~ conf.http_host ~ conf.cgi_script ~ "?" ~ conf.query_string));
        if (conf.request_method == "POST") {
          _the_can =
            "<font size=\"2\" 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=\"2\" 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 ~ 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="2" color="#666666">
<b>database:</b> <font size="2" 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=\"2\" color=\"#004000\">" ~ tf.text   ~ "</font>; "),
          (tf.title.empty  ? "" : "\"title:  <font size=\"2\" color=\"#004000\">" ~ tf.title  ~ "</font>; "),
          (tf.author.empty ? "" : "\"author: <font size=\"2\" color=\"#004000\">" ~ tf.author ~ "</font>; "),
          (tf.date.empty   ? "" : "\"date    <font size=\"2\" color=\"#004000\">" ~ tf.date   ~ "</font>; "),
          (tf.uid.empty    ? "" : "\"uid:    <font size=\"2\" color=\"#004000\">" ~ tf.uid    ~ "</font>; "),
          (tf.fn.empty     ? "" : "\"fn:     <font size=\"2\" color=\"#004000\">" ~ tf.fn     ~ "</font>; "),
          (tf.text.empty   ? "" :  "text:    <font size=\"2\" color=\"#004000\">" ~ tf.text   ~ "</font><br />"),
          (tf.title.empty  ? "" : "title:    <font size=\"2\" color=\"#004000\">" ~ tf.title  ~ "</font><br />"),
          (tf.author.empty ? "" :  "author:  <font size=\"2\" color=\"#004000\">" ~ tf.author ~ "</font><br />"),
          (tf.date.empty   ? "" :  "date:    <font size=\"2\" color=\"#004000\">" ~ tf.date   ~ "</font><br />"),
          (tf.uid.empty    ? "" : "\"uid:    <font size=\"2\" color=\"#004000\">" ~ tf.uid    ~ "</font>; "),
          (tf.fn.empty     ? "" : "\"fn:     <font size=\"2\" 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="2" color="#222222">
    <b>to search:</b> select which database to search (drop-down menu below); enter your search query (in the form above); and <b>click on the search button</b> (below)
    <br />
    <select name="db" size="1">
      %s
      <option value="%s">spine</option>
    </select>
    <input type="submit" value="SiSU search" />
    <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;
    match 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="sts" %s> result stats
      <input type="checkbox" name="url" %s> search url
      <input type="checkbox" name="se" %s> searched
      <input type="checkbox" name="tip" %s> available fields
      <input type="checkbox" name="sql" %s> sql statement
      <input type="hidden" name="smo" value="0">
    <br />
    </font>
  </td></tr>
  </table>
</form>
┃",
      "spine-search",
      (post_value("ec") == "checked") ? post_value("sf", "field") : "",
      provide_tip,
      search_note,
      the_can(post_value("sf", "field")),
      cv.db_selected,
      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("sts"),
      post_value("url"),
      post_value("se"),
      post_value("tip"),
      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",      "spine.search.db"); // selected_db == db
      cv.sql_match_limit  = set_value("sml", "1000");
      cv.sql_match_offset = set_value("smo", "0");
      cv.search_text      = set_value("sf",  "test");                         // remove test
      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_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 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,
  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=\"2\" color=\"#666666\">" ~ sql_select.the_body.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) {
        foreach (row; select_query_results) {
          if (row["uid"].as!string != _old_uid) {
            _old_uid = row["uid"].as!string;
            auto m = (row["date_published"].as!string).match(regex(r"^([0-9]{4})")); // breaks if row missing or no match?
            cgi.write(
              "<hr><a href=\""
                ~ "http://" ~ conf.http_host ~ "/"
                ~ row["language_document_char"].as!string ~ "/html/"
                ~ row["src_filename_base"].as!string ~ "/"
                ~ "toc.html"
              ~ "\">\""
                ~ row["title"].as!string ~ "\""
              ~ "</a> ("
              ~ m.hit
              ~ ") "
              ~ "["
              ~ row["language_document_char"].as!string
              ~ "] "
              ~ row["creator_author_last_first"].as!string
              ~ ":<br>\n"
            );
          }
          if (cv.results_type == "txt") {
            cgi.write(
              "<hr><a href=\""
                ~ "http://" ~ conf.http_host ~ "/"
                ~ row["language_document_char"].as!string ~ "/html/"
                ~ row["src_filename_base"].as!string ~ "/"
                ~ row["seg_name"].as!string ~ ".html#" ~ row["ocn"].as!string
              ~ "\">"
                ~ row["ocn"].as!string
              ~ "</a>"
              ~ "<br>"
              ~ row["body"].as!string
            );
          } else {
            cgi.write(
              "<a href=\""
                ~ "http://" ~ conf.http_host ~ "/"
                ~ row["language_document_char"].as!string ~ "/html/"
                ~ row["src_filename_base"].as!string ~ "/"
                ~ row["seg_name"].as!string ~ ".html#" ~ row["ocn"].as!string
              ~ "\">"
                ~ row["ocn"].as!string
              ~ "</a>, "
            );
          }
        }
        cgi.write( previous_next);
      } else { // offset_not_beyond_limit = false;
        cgi.write("select_query_results empty<p>\n");
      }
    }
    sql_search_query;
  }
  {
    db.close;
  }
  {
    string tail = format(q"┃
</body>
┃");
    cgi.write(tail);
  }
}
mixin GenericMain!cgi_function_intro;