// Discord Bus Event Integrations
// Purpose: Handles event-bus announcements to Discord channels.
// Scope: Processes supported event types and posts formatted messages/embeds.
const { EmbedBuilder, AttachmentBuilder } = require('discord.js');
const { buildBatteryStatusEmbed, buildBatteryCaption } = require('../batteryEmbeds');

function createBusEventHandler(deps) {
  const { logger, config, discordConfig, roverManager, rovers, schedulePresenceRotation, formatDuration, sendToChannel } = deps;
  const ADMIN_ALERT_EVENT_TYPES = new Set(['rover.online', 'rover.offline', 'rover.dockGuard', 'rover.helpNeeded', 'rover.helpCleared', 'battery.warn', 'battery.urgent', 'battery.docked', 'battery.undocked', 'battery.charging.start', 'battery.charging.stop', 'battery.locked', 'battery.unlocked']);
  let skippedFirstModeAnnouncement = false;

  function buildEmbed({ title, description, color, includeSiteUrl = true }) {
    const embed = new EmbedBuilder().setTitle(title || 'Update').setColor(color || 0x2196f3);
    const publicUrl = includeSiteUrl && config.publicUrl ? String(config.publicUrl) : '';
    if (description) embed.setDescription(publicUrl ? `${description}\n\n${publicUrl}` : description);
    else if (publicUrl) embed.setDescription(publicUrl);
    embed.setTimestamp(new Date());
    return embed;
  }


  async function announce({
    channelId,
    content,
    pingRoleId,
    prefixMentions = true,
    includeSiteUrl = true,
    color,
    title,
    description,
    embeds,
    files,
  }) {
    if (!channelId) return;
    const prefix = prefixMentions && pingRoleId ? `<@&${pingRoleId}> ` : '';
    const payloadEmbeds = Array.isArray(embeds) && embeds.length
      ? embeds
      : [buildEmbed({ title, description, color, includeSiteUrl })];
    await sendToChannel(channelId, `${prefix}${content || ''}`.trim(), { embeds: payloadEmbeds, files: Array.isArray(files) ? files : undefined }, { parse: [], roles: pingRoleId ? [pingRoleId] : [] }, !pingRoleId);
  }

  function handleBusEvent(event) {
    const { type, payload } = event || {};
    const channels = discordConfig.channels || {};
    const roles = discordConfig.roles || {};
    const roverId = payload?.roverId || null;
    if (roverId && !roverManager.canReplayRoverId(roverId) && !ADMIN_ALERT_EVENT_TYPES.has(type)) return;

    switch (type) {
      case 'mode.changed':
        if (!skippedFirstModeAnnouncement) { skippedFirstModeAnnouncement = true; schedulePresenceRotation(); break; }
        schedulePresenceRotation();
        break;
      case 'globalObjective.updated':
        schedulePresenceRotation();
        break;
      case 'communityGoal.updated':
        schedulePresenceRotation();
        break;
      case 'rover.locked':
        schedulePresenceRotation();
        break;
      case 'rover.unlocked':
        schedulePresenceRotation();
        break;
      case 'rovers.allUnlocked':
        schedulePresenceRotation();
        break;
      case 'rover.online':
        announce({ channelId: channels.adminAlerts, pingRoleId: roles.adminPing || null, color: 0x4caf50, title: 'Rover Online', description: `${payload?.roverId} is online.` });
        schedulePresenceRotation();
        break;
      case 'rover.offline':
        announce({ channelId: channels.adminAlerts, pingRoleId: roles.adminPing || null, color: 0xe53935, title: 'Rover Offline', description: `${payload?.roverId} went offline.` });
        schedulePresenceRotation();
        break;
      case 'rover.reboot.userRequested':
        announce({
          channelId: channels.adminAlerts,
          color: 0xf0b651,
          title: 'User Rover Reboot Requested',
          description: `${payload?.by || 'unknown user'} requested reboot for ${payload?.roverName || payload?.roverId || 'unknown rover'}.`,
        });
        break;
      case 'rover.dockGuard':
        announce({ channelId: channels.adminAlerts, color: 0xf0b651, title: 'Dock Guard Triggered', description: `${payload?.roverId} (${payload?.reasonText || 'undocked'}) for ${formatDuration(payload?.idleMs)}.` });
        break;
      case 'rover.helpNeeded':
        announce({
          channelId: channels.adminAlerts,
          pingRoleId: roles.adminPing || null,
          color: 0xef4444,
          title: 'Rover Needs Help',
          description: `${payload?.roverName || payload?.roverId || 'Unknown rover'}: ${payload?.reason || 'a sustained rover fault was detected'}.`,
        });
        break;
      case 'rover.helpCleared':
        announce({
          channelId: channels.adminAlerts,
          color: 0x4caf50,
          title: 'Rover Help Cleared',
          description: `${payload?.roverName || payload?.roverId || 'Unknown rover'} no longer needs help.`,
        });
        break;
      case 'battery.warn':
        announce({ channelId: channels.adminAlerts, pingRoleId: roles.adminPing || null, color: 0xf0b651, content: buildBatteryCaption(type, rovers.get(payload?.roverId || 'unknown')), embeds: [buildBatteryStatusEmbed({ color: 0xf0b651, records: Array.from(rovers.values()) })] });
        break;
      case 'battery.urgent':
        announce({ channelId: channels.adminAlerts, pingRoleId: roles.adminPing || null, color: 0xe53935, content: buildBatteryCaption(type, rovers.get(payload?.roverId || 'unknown')), embeds: [buildBatteryStatusEmbed({ color: 0xe53935, records: Array.from(rovers.values()) })] });
        break;
      case 'battery.docked':
      case 'battery.undocked':
      case 'battery.charging.start':
        announce({ channelId: channels.adminAlerts, color: 0x2196f3, content: buildBatteryCaption(type, rovers.get(payload?.roverId || 'unknown')), embeds: [buildBatteryStatusEmbed({ color: 0x2196f3, records: Array.from(rovers.values()) })] });
        break;
      case 'battery.charging.stop':
      case 'battery.locked':
        announce({ channelId: channels.adminAlerts, color: 0xf0b651, content: buildBatteryCaption(type, rovers.get(payload?.roverId || 'unknown')), embeds: [buildBatteryStatusEmbed({ color: 0xf0b651, records: Array.from(rovers.values()) })] });
        schedulePresenceRotation();
        break;
      case 'battery.unlocked':
        announce({ channelId: channels.adminAlerts, color: 0x4caf50, content: buildBatteryCaption(type, rovers.get(payload?.roverId || 'unknown')), embeds: [buildBatteryStatusEmbed({ color: 0x4caf50, records: Array.from(rovers.values()) })] });
        schedulePresenceRotation();
        break;
      case 'humanAlert.buttonPressed': {
        const imageBase64 = payload?.imageBase64 ? String(payload.imageBase64) : '';
        let attachment = null;
        if (imageBase64) {
          try {
            const imageBuffer = Buffer.from(imageBase64, 'base64');
            if (imageBuffer.length > 0) attachment = new AttachmentBuilder(imageBuffer, { name: 'human-alert-mosaic.jpg' });
          } catch (err) { logger.warn('Failed to decode human alert image for Discord', err.message); }
        }
        announce({
          channelId: channels.humanAlerts,
          pingRoleId: roles.humanAlertPing || null,
          content: payload?.message || 'Human alert button pressed.',
          embeds: [buildEmbed({ title: 'Human Alert Button Pressed', description: null, color: 0xe53935, includeSiteUrl: false })],
          files: attachment ? [attachment] : [],
          includeSiteUrl: false,
        });
        break;
      }
      // Replay requests are deliberately consumed by replayDeliveryService.
      // Discord registers only a preferred delivery provider, allowing the
      // same request to fall back locally without a second event subscriber.
      case 'buttonBox.discordStalkerPing': {
        const message = payload?.message ? String(payload.message) : 'Button box chaos reward triggered.';
        announce({
          channelId: channels.general,
          pingRoleId: roles.stalkerPing || null,
          content: message,
          color: 0xe91e63,
          title: 'Button Box',
          description: message,
          includeSiteUrl: false,
        });
        break;
      }
      case 'buttonBox.discordPingEveryone': {
        const message = payload?.message ? String(payload.message) : 'Button box chaos reward triggered.';
        sendToChannel(
          channels.general,
          `@everyone ${message}`.trim(),
          {
            embeds: [buildEmbed({ title: 'Button Box', description: message, color: 0xff3b30, includeSiteUrl: false })],
          },
          { parse: ['everyone'] },
          false,
        );
        break;
      }
      default:
        break;
    }
  }

  return { handleBusEvent };
}

module.exports = { createBusEventHandler };