import { WebSocket } from 'ws';
import { randomUUID } from 'crypto';
import { getDb } from '../db';
import { runAgentChat } from '../agent/pi-bridge';

export function handleChat(ws: WebSocket) {
  let conversationId: string | null = null;

  ws.on('message', async (raw) => {
    try {
      const msg = JSON.parse(raw.toString());

      if (msg.type === 'init') {
        conversationId = msg.conversationId || randomUUID();
        const history = getDb().prepare(
          'SELECT * FROM messages WHERE conversation_id = ? ORDER BY created_at'
        ).all(conversationId);
        ws.send(JSON.stringify({ type: 'history', data: { conversationId, messages: history } }));
        return;
      }

      if (msg.type === 'create_conversation') {
        const { title, accountId } = msg;
        conversationId = randomUUID();
        getDb().prepare(
          'INSERT INTO conversations (id, title, account_id) VALUES (?, ?, ?)'
        ).run(conversationId, title || '新对话', accountId || null);
        ws.send(JSON.stringify({ type: 'conversation_created', data: { id: conversationId, title } }));
        return;
      }

      if (msg.type === 'chat') {
        // Fallback: use conversationId from message if server state lost (e.g. after reconnect)
        if (!conversationId && msg.conversationId) {
          conversationId = msg.conversationId as string;
        }
        if (!conversationId) {
          ws.send(JSON.stringify({ type: 'error', data: { message: '没有活跃对话，请先创建或选择一个对话' } }));
          return;
        }
        await runAgentChat(ws, conversationId, msg.content, msg.images);
      }
    } catch (e) {
      console.error('WebSocket error:', e);
      ws.send(JSON.stringify({ type: 'error', data: { message: (e as Error).message } }));
    }
  });

  ws.on('close', () => {});
}