/**
 * Gamemaster Utilities
 * Functions for fetching and processing PokeMiners gamemaster data
 */

const POKEMINERS_GAMEMASTER_URL =
  'https://raw.githubusercontent.com/PokeMiners/game_masters/master/latest/latest.json';

/**
 * Fetch latest gamemaster data from PokeMiners GitHub
 * @returns {Promise<Array>} Gamemaster data array
 */
export async function fetchLatestGamemaster() {
  try {
    const response = await fetch(POKEMINERS_GAMEMASTER_URL);
    if (!response.ok) {
      throw new Error(`Failed to fetch gamemaster: ${response.statusText}`);
    }
    return await response.json();
  } catch (error) {
    console.error('Error fetching gamemaster:', error);
    throw error;
  }
}

/**
 * Break up gamemaster into separate categories
 * @param {Array} gamemaster - Full gamemaster data
 * @returns {Object} Separated data {pokemon, pokemonAllForms, moves}
 */
export function breakUpGamemaster(gamemaster) {
  const regionCheck = ['alola', 'galarian', 'hisuian', 'paldea'];

  const result = gamemaster.reduce(
    (acc, item) => {
      const templateId = item.templateId;

      // POKEMON FILTER
      // If the templateId begins with 'V' AND includes 'pokemon'
      if (
        templateId.startsWith('V') &&
        templateId.toLowerCase().includes('pokemon')
      ) {
        const pokemonSettings = item.data?.pokemonSettings;
        const pokemonId = pokemonSettings?.pokemonId;

        // Add to allFormsCostumes (includes everything)
        acc.pokemonAllForms.push(item);

        // Add to pokemon (filtered - first occurrence OR regional forms)
        // Check if this is a regional form by looking at the form string
        const form = pokemonSettings?.form;
        const isRegionalForm =
          form && typeof form === 'string'
            ? regionCheck.includes(form.split('_')[1]?.toLowerCase())
            : false;

        if (
          !acc.pokemonSeen.has(pokemonId) ||
          (acc.pokemonSeen.has(pokemonId) && isRegionalForm)
        ) {
          acc.pokemonSeen.add(pokemonId);
          acc.pokemon.push(item);
        }
      }

      // POKEMON MOVE FILTER
      if (
        templateId.startsWith('V') &&
        templateId.toLowerCase().includes('move')
      ) {
        const moveSettings = item.data?.moveSettings;
        const moveId = moveSettings?.movementId;
        if (!acc.moveSeen.has(moveId)) {
          acc.moveSeen.add(moveId);
          acc.moves.push(item);
        }
      }

      return acc;
    },
    {
      pokemon: [],
      pokemonAllForms: [],
      moves: [],
      pokemonSeen: new Set(),
      moveSeen: new Set()
    }
  );

  // Clean up the Sets before returning
  delete result.pokemonSeen;
  delete result.moveSeen;

  return result;
}

/**
 * Download JSON data as a file
 * @param {Object|Array} data - Data to download
 * @param {string} filename - Filename for download
 */
export function downloadJson(data, filename) {
  const json = JSON.stringify(data, null, 2);
  const blob = new Blob([json], { type: 'application/json' });
  const url = URL.createObjectURL(blob);

  const link = document.createElement('a');
  link.href = url;
  link.download = filename;
  document.body.appendChild(link);
  link.click();
  document.body.removeChild(link);
  URL.revokeObjectURL(url);
}

/**
 * Calculate file size in MB
 * @param {Object|Array} data - Data to measure
 * @returns {string} Size in MB formatted
 */
export function calculateFileSize(data) {
  const json = JSON.stringify(data);
  const bytes = new Blob([json]).size;
  const mb = bytes / (1024 * 1024);
  return `${mb.toFixed(2)} MB`;
}

/**
 * Get statistics about gamemaster data
 * @param {Object} brokenUpData - Result from breakUpGamemaster
 * @returns {Object} Statistics
 */
export function getGamemasterStats(brokenUpData) {
  return {
    pokemonCount: brokenUpData.pokemon.length,
    allFormsCount: brokenUpData.pokemonAllForms.length,
    movesCount: brokenUpData.moves.length,
    pokemonSize: calculateFileSize(brokenUpData.pokemon),
    allFormsSize: calculateFileSize(brokenUpData.pokemonAllForms),
    movesSize: calculateFileSize(brokenUpData.moves)
  };
}