/**
 * OKR API — Objective - Key Result 目标管理路由
 *
 * 旧路径 /api/goals/* 已在 index.js / agent-server.js 注册为向后兼容别名。
 *
 * GET    /api/okr                      → 列出所有目标
 * POST   /api/okr                      → 创建新目标
 * GET    /api/okr/:objectiveId              → 获取完整 OKR 树
 * PUT    /api/okr/:objectiveId              → 更新目标元数据
 * POST   /api/okr/:objectiveId/nodes        → 添加节点
 * GET    /api/okr/:objectiveId/nodes/:nodeId → 获取节点 + 上下文
 * PUT    /api/okr/:objectiveId/nodes/:nodeId → 更新节点状态
 * GET    /api/okr/:objectiveId/progress     → 获取进度统计
 *
 * 参考: docs/architecture-v5.md 第二章
 */

const { Router } = require('express');
const { OkrService } = require('../services/okr-service');

const router = Router();
const okr = new OkrService();

// ── 列出所有目标 ──
router.get('/', (req, res) => {
  res.json(okr.list());
});

// ── 创建新目标 ──
router.post('/', (req, res) => {
  try {
    const { title, description, owner } = req.body;
    if (!title || !owner) {
      return res.status(400).json({ error: 'title and owner are required' });
    }
    const objective = okr.create({ title, description, owner });
    res.status(201).json(objective);
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

// ── 获取完整 OKR 树 ──
router.get('/:objectiveId', (req, res) => {
  const objective = okr.get(req.params.objectiveId);
  if (!objective) return res.status(404).json({ error: 'Objective not found' });
  res.json(objective);
});

// ── 更新目标元数据 ──
router.put('/:objectiveId', (req, res) => {
  const result = okr.updateObjective(req.params.objectiveId, req.body);
  if (!result) return res.status(404).json({ error: 'Objective not found' });
  res.json(result);
});

// ── 添加节点 ──
router.post('/:objectiveId/nodes', (req, res) => {
  try {
    const { parentNodeId, title, owner, priority } = req.body;
    if (!title || !owner) {
      return res.status(400).json({ error: 'title and owner are required' });
    }

    const result = okr.addNode(req.params.objectiveId, parentNodeId || null, {
      title, owner, priority,
    });

    if (!result) return res.status(404).json({ error: 'Objective not found' });
    res.status(201).json({ nodeId: result.nodeId, node: result.objective.nodes[result.nodeId] });
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

// ── 获取节点 + 上下文 ──
router.get('/:objectiveId/nodes/:nodeId', (req, res) => {
  const node = okr.getNode(req.params.objectiveId, req.params.nodeId);
  if (!node) return res.status(404).json({ error: 'Node not found' });
  res.json(node);
});

// ── 更新节点状态 ──
router.put('/:objectiveId/nodes/:nodeId', (req, res) => {
  const result = okr.updateNode(req.params.objectiveId, req.params.nodeId, req.body);
  if (!result) return res.status(404).json({ error: 'Node not found' });
  res.json({ nodeId: result.nodeId, node: result.node });
});

// ── 获取进度 ──
router.get('/:objectiveId/progress', (req, res) => {
  const progress = okr.getProgress(req.params.objectiveId);
  if (!progress) return res.status(404).json({ error: 'Objective not found' });
  res.json(progress);
});

module.exports = router;