import {
  Client,
  GatewayIntentBits,
  ChannelType,
  REST,
  Routes,
  TextChannel,
  Interaction,
} from "discord.js";
import { DisclawDatabase } from "./db/database";
import { DisclawConfig, EnvConfig } from "./config/loader";
import { newAgentCommand, handleNewAgent } from "./commands/new-agent";
import { routeMessage } from "./router";
import { childLogger } from "./runtime/logger";

const log = childLogger("bot");

export async function startBot(
  envConfig: EnvConfig,
  disclawConfig: DisclawConfig,
  db: DisclawDatabase
): Promise<Client> {
  const client = new Client({
    intents: [
      GatewayIntentBits.Guilds,
      GatewayIntentBits.GuildMessages,
      GatewayIntentBits.MessageContent,
    ],
  });

  // Track the management channel id once resolved
  let managementChannelId: string | null = null;

  // --- Event: Ready ---
  client.once("ready", async () => {
    if (!client.user) return;
    log.info({ tag: client.user.tag }, "Bot online");

    const guild = envConfig.DISCORD_GUILD_ID
      ? client.guilds.cache.get(envConfig.DISCORD_GUILD_ID)
      : client.guilds.cache.first();

    if (!guild) {
      log.error("No guild found. Is the bot added to a server?");
      process.exit(1);
    }

    log.info({ guildName: guild.name, guildId: guild.id }, "Connected to guild");

    // --- Ensure management channel exists ---
    const managementName = disclawConfig.management_channel;
    let existingWorkspace = db.getWorkspaceByName(managementName);

    if (existingWorkspace) {
      // Verify the channel still exists on Discord
      const existingChannel = guild.channels.cache.get(
        existingWorkspace.channel_id
      );
      if (existingChannel) {
        managementChannelId = existingWorkspace.channel_id;
        log.info({ channelName: managementName }, "Management channel found");
      } else {
        // Channel was deleted from Discord, recreate it
        existingWorkspace = undefined;
      }
    }

    if (!existingWorkspace) {
      // Look for an existing channel with that name first
      let mgmtChannel: TextChannel;

      const found = guild.channels.cache.find(
        (ch) =>
          ch.type === ChannelType.GuildText && ch.name === managementName
      ) as TextChannel | undefined;

      if (found) {
        db.createWorkspace(
          found.id,
          guild.id,
          managementName,
          "__management__"
        );
        managementChannelId = found.id;
        mgmtChannel = found;
        log.info({ channelName: managementName }, "Adopted existing channel");
      } else {
        const newChannel = await guild.channels.create({
          name: managementName,
          type: ChannelType.GuildText,
          topic: "DisClaw Management -- verwende /new-agent um Agenten zu erstellen",
        });
        db.createWorkspace(
          newChannel.id,
          guild.id,
          managementName,
          "__management__"
        );
        managementChannelId = newChannel.id;
        mgmtChannel = newChannel;
        log.info({ channelName: managementName }, "Created management channel");
      }

      // Send welcome message using the direct channel reference
      await mgmtChannel
        .send(
          "DisClaw ist bereit. Verwende `/new-agent` um einen neuen Agenten zu erstellen."
        )
        .catch(() => {});
    }

    // --- Register slash commands ---
    const rest = new REST({ version: "10" }).setToken(
      envConfig.DISCORD_BOT_TOKEN
    );

    try {
      await rest.put(
        Routes.applicationGuildCommands(client.user.id, guild.id),
        {
          body: [newAgentCommand.toJSON()],
        }
      );
      log.info("Slash commands registered.");
    } catch (err) {
      log.error({ err }, "Failed to register slash commands");
    }
  });

  // --- Event: interactionCreate (slash commands) ---
  client.on("interactionCreate", async (interaction: Interaction) => {
    if (!interaction.isChatInputCommand()) return;

    if (interaction.commandName === "new-agent") {
      await handleNewAgent(interaction, db, disclawConfig);
    }
  });

  // --- Event: messageCreate (agent routing) ---
  client.on("messageCreate", async (message) => {
    // Ignore bot messages
    if (message.author.bot) return;

    // Only handle text channels in guilds
    if (!message.guild || message.channel.type !== ChannelType.GuildText) return;

    await routeMessage(message, db, disclawConfig, managementChannelId);
  });

  // --- Login ---
  await client.login(envConfig.DISCORD_BOT_TOKEN);

  return client;
}