#!/usr/bin/env rdmd
/+
  - read in file .sst .ssi .ssm
  - loop twice
    - first
      - check for and skip code blocks
      - use unique code marker for endnote markers in text and give an endnote
        number ★1, increment
      - extract all endnotes in array
    - second
      - check that the footnote marker number count matches the number of notes
        in the array
        - if they match either:
            - substitute each endnote marker with the array footnote[number-1]
            - substitute each endnote marker with footnote
              as inlined footnote markup (footnote number not needed)
        - if they do not match exit
  - check whether changes have been made
    - if so write file with inline footnotes in sub-directory converted_output_/
      using the same name as the original file
    - else, exit
+/
import std.stdio;
import std.file;
import std.array : split, join;
import std.exception;
// import std.range;
import core.stdc.errno;
import std.regex;
import std.format;
import std.conv;
void main(string[] args) {
  static heading_a               = ctRegex!(`^:?[A][~] `, "m");
  static comment                 = ctRegex!(`^%+ `);
  static block_tic_code_open     = ctRegex!("^`{3} code(?:[.](?P<syntax>[a-z][0-9a-z#+_]+))?(?:[(](?P<attrib>[ a-zA-Z0-9;:,]*)[)])?");
  static block_tic_close         = ctRegex!("^(`{3})$","m");
  static block_curly_code_open   = ctRegex!(`^(?:code(?:[.](?P<syntax>[a-z][0-9a-z_]+))?(?:[(](?P<attrib>[ a-zA-Z0-9;:,]*)[)])?[{][ ]*$)`);
  static block_curly_code_close  = ctRegex!(`^([}]code)`);
  auto rgx_endnote_ref           = ctRegex!(`([~]\^)(?P<tail>[)\]]? |$)`, "gm");
  auto rgx_endnote               = ctRegex!(`^\^~\s+(.+|\n)`, "gm");
  char[][] header0Content1(in string src_text) { // cast(char[])
    /+ split string on _first_ match of "^:?A~\s" into [header, content] array/tuple +/
    char[][] header_and_content;
    auto m = (cast(char[]) src_text).matchFirst(heading_a);
    header_and_content ~= m.pre;
    header_and_content ~= m.hit ~ m.post;
    assert(header_and_content.length == 2,
      "document markup is broken, header body split == "
      ~ header_and_content.length.to!string
      ~ "; (header / body array split should == 2 (split is on level A~))"
    );
    return header_and_content;
  }
  string format_body_string(string s) {
    string o;
    o = s
     .replaceAll(regex("^<(?:/[ ]*)?br>[ ]*"), " \\\\ ")
     .replaceAll(regex("[ ]*<(?:/[ ]*)?br>$"), " \\\\")
     .replaceAll(regex("[ ]*<(?:/[ ]*)?br>[ ]*"), " \\\\ ");
    return o;
  }
  string format_header_string(string s) {
    string o;
    o = s
     .replaceAll(regex("\""), "\\\"")
     .replaceAll(regex("[ ]*<(?:/[ ]*)?br>$"), " \\\\")
     .replaceAll(regex("[ ]*<(?:/[ ]*)?br>[ ]*"), " \\\\ ");
    return o;
  }
  string format_main_header(string hm, string hs = "", string c = "") {
    string o;
    if (c.length == 0) {
      o ~= hm ~ ":\n";
    } else {
      o ~= hm ~ ":\n"
        ~ "  " ~ hs ~ ": "
        ~ "\"" ~ format_header_string(c) ~ "\"\n";
    }
    return o;
  }
  string format_sub_header(string hs, string c) {
    string o;
    o ~= "  " ~ hs ~ ": "
      ~ "\"" ~ format_header_string(c) ~ "\"\n";
    return o;
  }
  foreach(arg; args[1..$]) {
    if (
      !(arg.match(regex(r"--\w+")))
      && arg.match(regex(r"\w+?\.ss[itm]"))
    ) {
      writeln(arg);
      string filename                  = arg;
      try {
        string[] munged_header, munged_contents, munged_endnotes, endnote_refs;
        char[][] hc;
        char[] src_header;
        string[] headers;
        char[] src_txt;
        string[] paragraphs;
        enum codeBlock { off, curly, tic, }
        string _tmp_header;
        int endnote_ref_count          = 0;
        int code_block_status          = codeBlock.off;
        string text                    = filename.readText;
        if (arg.match(regex(r"\w+?\.ss[tm]"))) {
          hc                           = header0Content1(text);
          src_header                   = hc[0];
          headers                      = src_header.to!string.split("\n\n");
          src_txt                      = hc[1];
          paragraphs                   = src_txt.to!string.split("\n\n");
        } else if (arg.match(regex(r"\w+?\.ssi"))) {
          headers                      = [];
          paragraphs                   = text.split("\n\n");
        }
        if (headers.length > 0) {
          headers[0] = headers[0].replaceFirst(regex(r"^%\s+SiSU.+", "i"), "# SiSU 8.0 spine (auto-conversion)");
          foreach (h_; headers) {
            _tmp_header = "";
            if (auto m = h_.match(regex(r"^%\s*", "m"))) {
              h_ = h_.replaceAll(regex(r"^%\s*", "m"), "# ") ~ "\n";
            }
            if (h_.match(regex(r"^@title:|@subtitle"))) {
              if (auto m = h_.match(regex(r"^@(?P<h>title):(?:[ ]+(?P<c>.+)|\n)"))) {
                _tmp_header ~= format_main_header(m.captures["h"], "main", m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^@(?P<h>subtitle):(?:[ ]+(?P<c>.+)|$)"))) {
                if (m.captures["c"].length == 0) {
                } else {
                  _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
                }
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>main):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:sub(?:title)?:(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header("subtitle", m.captures["c"]);
              }
            } else if (h_.match(regex(r"^@creator:|@author:"))) {
              if (auto m = h_.match(regex(r"^(?:@creator:|@author:)(?:[ ]+(?P<c>.+)|\n)"))) {
                _tmp_header ~= format_main_header("creator", "author", m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>author):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
            } else if (h_.match(regex(r"^@rights:"))) {
              if (auto m = h_.match(regex(r"^@(?P<h>rights):(?:[ ]+(?P<c>.+)|\n)"))) {
                _tmp_header ~= format_main_header(m.captures["h"], "copyright", m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>copyright):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:licen[cs]e:(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header("license", m.captures["c"]);
              }
            } else if (h_.match(regex(r"^@date:|@date\."))) {
              if (auto m = h_.match(regex(r"^@(?P<h>date):(?:[ ]+(?P<c>.+)|\n)"))) {
                _tmp_header ~= format_main_header(m.captures["h"], "published", m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>published):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>available):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>modified):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>created):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>issued):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>valid):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^@date\.(?P<h>available):[ ]+(?P<c>.+)$"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^@date\.(?P<h>modified):[ ]+(?P<c>.+)$"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^@date\.(?P<h>created):[ ]+(?P<c>.+)$"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^@date\.(?P<h>issued):[ ]+(?P<c>.+)$"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^@date\.(?P<h>valid):[ ]+(?P<c>.+)$"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
            } else if (h_.match(regex(r"^@classify:"))) {
              if (auto m = h_.match(regex(r"^@classify:"))) {
                _tmp_header ~= "classify:\n";
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>topic_register):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:type:(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= "#  type: " ~ "\"" ~ m.captures["c"] ~ "\"\n";
              }
            } else if (h_.match(regex(r"^(?:@identifier:|@identify:)"))) {
              if (auto m = h_.match(regex(r"^(?:@identifier:|@idenfify)"))) {
                _tmp_header ~= "identify:\n";
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>oclc):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>isbn):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>dewey):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
            } else if (h_.match(regex(r"^@publisher:"))) {
              if (auto m = h_.match(regex(r"^@publisher:[ ]+(?P<c>.+)$"))) {
                _tmp_header ~= "publisher: " ~  "\"" ~ m.captures["c"] ~ "\"\n";
              }
            } else if (h_.match(regex(r"^@make:"))) {
              // writeln(h_);
              if (auto m = h_.match(regex(r"^@make:"))) {
                _tmp_header ~= "make:\n";
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>breaks):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>num_top):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>headings):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>italics):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>bold):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>emphasis):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>substitute):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>texpdf_font):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>home_button_text):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>home_button_image):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>cover_image):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              if (auto m = h_.match(regex(r"^\s+:(?P<h>footer):(?:[ ]+(?P<c>.+)|$)", "m"))) {
                _tmp_header ~= format_sub_header(m.captures["h"], m.captures["c"]);
              }
              // writeln(_tmp_header);
            } else if (h_.match(regex(r"^@\w+:"))) {
              _tmp_header ~= "# " ~ h_.split("\n").join("\n# ") ~ "\n";
            } else if (h_.match(regex(r"^\s+:\w+:", "m"))) {
              if (auto m = h_.match(regex(r"^(?P<g>\s+:\w+:.*)"))) {
                _tmp_header ~= "# " ~ m.captures["g"] ~ "\n";
              }
            }
            if (h_.match(regex(r"^#", "m"))) {
              if (auto m = h_.match(regex(r"^(?P<g>#.*)", "m"))) {
                _tmp_header ~= m.captures["g"] ~ "\n";
              }
             }
            if (_tmp_header.length > 0) {
              munged_header ~= _tmp_header.split("\n\n");
            } else if (h_.length > 0) {
              writeln("munging required: ", h_);
              h_ = h_.replaceAll((regex(r"\n\n\n+", "m")), "\n\n");
              munged_header ~= h_;
            }
          }
          // writeln(munged_header.join("\n"));
        }
        foreach (paragraph; paragraphs) {                                                                                  /+ loop to gather binary endnotes +/
          if (code_block_status == codeBlock.off
            && paragraph.match(rgx_endnote)
          ) {
            munged_endnotes ~= replaceAll!(m => m[1])
              (paragraph, rgx_endnote);
          } else {
            if ( code_block_status != codeBlock.off
              || paragraph.matchFirst(block_curly_code_open)
              || paragraph.matchFirst(block_tic_code_open)
            ) { /+ code blocks identified, no munging +/
              if ((code_block_status == codeBlock.curly
                  && paragraph.matchFirst(block_curly_code_close))
                || (code_block_status == codeBlock.tic
                  && paragraph.matchFirst(block_tic_close))
              ) {
                code_block_status = codeBlock.off;
              } else if (paragraph.matchFirst(block_curly_code_open)) {
                code_block_status = codeBlock.curly;
              } else if (paragraph.matchFirst(block_tic_code_open)) {
                code_block_status = codeBlock.tic;
              }
              munged_contents ~= paragraph;
            } else { /+ regular content, not a code block +/
              if (auto m = paragraph.matchAll(rgx_endnote_ref)) {
                foreach (n; m) {
                  endnote_ref_count++; // endnote_refs ~= (n.captures[1]);
                }
              }
              paragraph = format_body_string(paragraph);
              // paragraph = replaceAll!(m => " \\\\ " )
              //   (paragraph, regex(r"\s*<(?:/\s*|:)?br>\s*")); // (paragraph, regex(r"(<br>)"));
              munged_contents ~= paragraph;
            }
          }
        }
        {
          import std.outbuffer;
          auto buffer = new OutBuffer();
          if (munged_header.length > 0) {
            foreach (header; munged_header) { /+ loop to inline endnotes +/
              buffer.write(header ~ "\n");
            }
          }
          if (munged_endnotes.length == endnote_ref_count) {
            int endnote_count = -1;
            foreach (k, content; munged_contents) { /+ loop to inline endnotes +/
              content = replaceAll!(m => "~{ " ~ munged_endnotes[++endnote_count] ~ " }~" ~ m["tail"] )
                (content, rgx_endnote_ref); // endnote_ref cannot occur in a code block or else fail
              buffer.write(content ~ ((k == munged_contents.length - 1) ? "" : "\n\n"));
            }
            if (buffer) {
              try {
                string dir_out = "converted_output_";
                string path_and_file_out = dir_out ~ "/" ~ filename;
                dir_out.mkdirRecurse;
                auto f = File(path_and_file_out, "w");
                f.write(buffer);
                // writeln("wrote: ", path_and_file_out);
              } catch (FileException ex) {
                writeln("did not write file");
                // Handle errors
              }
            }
          } else {
            foreach (content; munged_contents) { /+ loop to inline endnotes +/
              buffer.write(content ~ "\n\n");
            }
          }
        }
      } catch (ErrnoException ex) {
        switch(ex.errno) {
          case EPERM:
          case EACCES: // Permission denied
            break;
          case ENOENT: // File does not exist
            break;
          default:     // Handle other errors
            break;
        }
      }
    }
  }
}