import {
  SlashCommandBuilder,
  EmbedBuilder,
  ChatInputCommandInteraction,
} from 'discord.js';
import {
  listGameNames,
  getGame,
  setGame,
  deleteGame,
  deleteField,
} from './utils/db/game';

// Initialise the command data.
export const data = new SlashCommandBuilder()
  .setName('game')
  .setDescription('Perform ButlerBot game database operations.')
  .addSubcommand((subcommand) =>
    subcommand.setName('list').setDescription('List all games in the database.')
  )
  .addSubcommand((subcommand) =>
    subcommand
      .setName('get')
      .setDescription('Get a game from the database.')
      .addStringOption((option) =>
        option
          .setName('game')
          .setDescription('The name of the game to get.')
          .setRequired(true)
      )
  )
  .addSubcommand((subcommand) =>
    subcommand
      .setName('set')
      .setDescription('Set a key value pair on a game in the database.')
      .addStringOption((option) =>
        option
          .setName('game')
          .setDescription('The name of the game to set the field in.')
          .setRequired(true)
      )
      .addStringOption((option) =>
        option
          .setName('key')
          .setDescription('The key or label to set.')
          .setRequired(true)
      )
      .addStringOption((option) =>
        option
          .setName('value')
          .setDescription('The value of the field to set.')
          .setRequired(true)
          .setMinLength(1)
          .setMaxLength(1024)
      )
  )
  .addSubcommand((subcommand) =>
    subcommand
      .setName('delete')
      .setDescription('Delete a game, or a field from a game.')
      .addStringOption((option) =>
        option
          .setName('game')
          .setDescription(
            'The name of the game to remove, or remove a field from.'
          )
          .setRequired(true)
      )
      .addStringOption((option) =>
        option
          .setName('key')
          .setDescription('The key or label of the field to remove.')
          .setRequired(false)
      )
  );

console.log(`Loaded ${data.name} command.`);

/**
 * Handle the interaction for the game command.
 * @param interaction The interaction that triggered the command.
 * @returns A promise that resolves when the command is finished executing.
 */
export async function execute(
  interaction: ChatInputCommandInteraction
): Promise<void> {
  await interaction.deferReply();

  const subcommand = interaction.options.getSubcommand();

  switch (subcommand) {
    case 'list': {
      const gameNames = await listGameNames();

      if (gameNames.length === 0) {
        await interaction.editReply('No games found in the database.');
        return;
      }

      const embed = new EmbedBuilder()
        .setTitle('Game Database')
        .setColor(0xff0000)
        .setDescription('List of games in the database.');

      embed.addFields({
        name: 'Games',
        value: gameNames.map((game) => game.game).join('\n'),
      });

      await interaction.editReply({ embeds: [embed] });
      break;
    }

    case 'get': {
      const gameName = interaction.options.getString('game', true);

      const game = await getGame(gameName);

      if (!game) {
        await interaction.editReply(
          `Game ${gameName} not found in the database.`
        );
        return;
      }

      try {
        const embed = createEmbedFromGame(game);
        await interaction.editReply({ embeds: [embed] });
      } catch (error) {
        await interaction.editReply(
          'Embed too large to send. Game has not been retrieved.'
        );
      }
      break;
    }

    case 'set': {
      const gameName = interaction.options.getString('game', true);
      const key = interaction.options.getString('key', true);
      const value = interaction.options.getString('value', true);

      const oldGame = await getGame(gameName);
      await setGame(gameName, key, value);
      const updatedGame = await getGame(gameName);

      try {
        const embed = createEmbedFromGame(updatedGame);
        await interaction.editReply({ embeds: [embed] });
      } catch (error) {
        // Revert game back to original state if the embed is too large.
        if (oldGame) {
          // If key already existed, revert to old value, else delete the key.
          if (oldGame[key]) {
            await setGame(gameName, key, oldGame[key]);
          } else {
            await deleteField(gameName, key);
          }
        }
        await interaction.editReply(
          'Embed too large to send. Game has not been updated.'
        );
      }
      break;
    }

    case 'delete': {
      const gameName = interaction.options.getString('game', true);
      const key = interaction.options.getString('key');

      if (key) {
        await deleteField(gameName, key);
        const updatedGame = await getGame(gameName);

        if (!updatedGame) {
          await interaction.editReply(
            `Game ${gameName} deleted from the database.`
          );
          return;
        }

        try {
          const embed = createEmbedFromGame(updatedGame);
          await interaction.editReply({ embeds: [embed] });
        } catch (error) {
          await interaction.editReply(
            'Embed too large to send. Field deleted from game but game has not been retrieved.'
          );
        }
      } else {
        await deleteGame(gameName);
        await interaction.editReply(
          `Game ${gameName} deleted from the database.`
        );
      }
      break;
    }

    default:
      await interaction.editReply('Unknown subcommand.');
      break;
  }
}

/**
 * Create an embed from a game object.
 * @param game The game object containing key-value pairs.
 * @returns The embed object to be sent in the interaction.
 */
function createEmbedFromGame(game: any): EmbedBuilder {
  const embed = new EmbedBuilder().setTitle(game.game).setColor(0xff0000);

  // Add fields for each key value pair - skip name, _id and guild.
  embed.addFields(
    Object.entries(game)
      .filter(([key]) => !['_id', 'game', 'guild'].includes(key))
      .map(([key, value]) => ({ name: key, value: String(value) }))
  );

  if (embed.length > 6000) {
    throw new Error('Embed size exceeds maximum.');
  }

  return embed;
}