#include "convertmarkdown.h"

#include <cerrno>
#include <cstring>
#include <fstream>
#include <iostream>

static bool markdown_needs_escape (char ch) {
  switch (ch) {
    case '\\':
    case '`':
    case '*':
    case '_':
    case '[':
    case ']':
    case '<':
    case '>':
    case '#':
    case '!':
    case '|':
      return true;
    default:
      return false;
  }
}

static std::string markdown_escape (const std::string &s) {
  std::string out;
  out.reserve (s.size() + s.size() / 8);
  for (char ch : s) {
    if (markdown_needs_escape (ch))
      out.push_back ('\\');
    out.push_back (ch);
  }
  return out;
}

bool ConverterMarkdown::save (const std::string &output_file_name) {
  if (!parse())
    return false;

  std::ofstream output (output_file_name, std::ios::trunc);
  if (!output.is_open()) {
    std::cerr << "Failed to open output file: "
              << output_file_name
              << " (" << std::strerror (errno) << ")\n";
    set_error_code (3);
    return false;
  }

  const auto &book_titles = titles();
  for (std::size_t i = 0; i < book_titles.size(); ++i) {
    const auto &title = book_titles[i];
    output << "# " << markdown_escape (title) << "\n\n";

    for (std::size_t quote_index = 0;
         quote_index < quote_count (title);
         ++quote_index) {
      output << "## " << markdown_escape (quote_meta (title, quote_index))
             << "\n\n";

      const auto &text_lines = quote_text_lines (title, quote_index);
      std::size_t line_index = 0;
      if (!text_lines.empty() && text_lines.front().empty())
        line_index = 1;

      for (; line_index < text_lines.size(); ++line_index) {
        if (text_lines[line_index].empty())
          output << ">\n";
        else
          output << "> " << markdown_escape (text_lines[line_index]) << '\n';
      }

      output << "\n### Notes\n\n";
    }
  }

  set_error_code (0);
  return true;
}