#!/usr/bin/env node

/*! Copyright Twitter Inc. and other contributors. Licensed under MIT *//*
    https://github.com/twitter/twemoji/blob/gh-pages/LICENSE
*/

// dependencies
var fs = require('fs');
var path = require('path');

var regex = new RegExp(fs.readFileSync(file('scripts/regex')).toString(), 'g');

function fromCodePoint(codepoint) {
  var code = typeof codepoint === 'string' ?
        parseInt(codepoint, 16) : codepoint;
  if (code < 0x10000) {
    return String.fromCharCode(code);
  }
  code -= 0x10000;
  return String.fromCharCode(
    0xD800 + (code >> 10),
    0xDC00 + (code & 0x3FF)
  );
}

function countEmoji(emoji) {
  var count = 0;
  regex.lastIndex = 0;
  while (regex.exec(emoji)) {
    count++;
  }
  return count;
}

function file(which) {
  return path.join(__dirname, '..', which);
}

fs.readdir(file('assets'), function (err, files) {
  var page = fs.readFileSync(file('templates/preview.html')).toString().replace(
    '{{emoji-list}}',
    '<li>' + files.map(function (filename) {
      var codepoints = filename.replace('.ai', '').split('-');
      var emoji = codepoints.map(function(codepoint) {
        return fromCodePoint(codepoint);
      }).join('');
      if (countEmoji(emoji + '\ufe0f') === 1) {
        codepoints.push('fe0f');
      }
      return codepoints.map(function (codepoint) {
        return '&#x' + codepoint.toUpperCase() + ';';
      }).join('');
    }).join('</li>\n      <li>')+ '</li>'
  );
  fs.writeFileSync(
    file('test/preview.html'),
    page.replace(
      '{{emoji-options}}',
      JSON.stringify({
        size: 72
      })
    )
  );
  fs.writeFileSync(
    file('test/preview-svg.html'),
    page.replace(
      '{{emoji-options}}',
      JSON.stringify({
        folder: '../svg',
        ext: '.svg',
        base: ''
      })
    )
  );
});