/**
 * 星环OPC中心 — Dashboard 监控中心 API
 *
 * 路由:
 *   GET /opc/admin/api/dashboard — 获取监控中心数据
 *   POST /opc/admin/api/alerts/:id/dismiss — 忽略预警
 */

import type { IncomingMessage, ServerResponse } from "node:http";
import type { OpenClawPluginApi } from "openclaw/plugin-sdk";
import type { OpcDatabase } from "../db/index.js";
import {
  generateDashboardHtml,
  type DashboardData,
  type DashboardMetrics,
  type DashboardAlert,
  type DashboardTodo,
  type DashboardSuggestion,
} from "../web/dashboard-ui.js";

interface DashboardRow {
  total_income: number;
  total_expense: number;
}

interface PaymentRow {
  id: string;
  company_id: string;
  direction: string;
  counterparty: string;
  amount: number;
  paid_amount: number;
  status: string;
  due_date: string;
  category: string;
}

interface AlertRow {
  id: string;
  company_id: string;
  title: string;
  severity: string;
  category: string;
  status: string;
  message: string;
  created_at: string;
}

interface TodoRow {
  id: string;
  company_id: string;
  title: string;
  priority: string;
  category: string;
  status: string;
  due_date: string;
  description: string;
}

/**
 * 注册 Dashboard API 路由
 */
export function registerDashboardApiRoutes(api: OpenClawPluginApi, db: OpcDatabase): void {
  const handler = async (req: IncomingMessage, res: ServerResponse): Promise<boolean> => {
    const rawUrl = req.url ?? "";
    const urlObj = new URL(rawUrl, "http://localhost");
    const pathname = urlObj.pathname;
    const method = req.method?.toUpperCase() ?? "GET";

    // GET /opc/admin/api/dashboard
    if (pathname === "/opc/admin/api/dashboard" && method === "GET") {
      try {
        const data = getDashboardData(db);
        const html = generateDashboardHtml(data);
        res.writeHead(200, { "Content-Type": "application/json; charset=utf-8" });
        res.end(JSON.stringify({ ...data, html }));
      } catch (err) {
        res.writeHead(500, { "Content-Type": "application/json; charset=utf-8" });
        res.end(JSON.stringify({ error: err instanceof Error ? err.message : String(err) }));
      }
      return true;
    }

    // POST /opc/admin/api/alerts/:id/dismiss
    const alertMatch = pathname.match(/^\/opc\/admin\/api\/alerts\/([^/]+)\/dismiss$/);
    if (alertMatch && method === "POST") {
      try {
        const alertId = alertMatch[1];

        if (!alertId) {
          res.writeHead(400, { "Content-Type": "application/json; charset=utf-8" });
          res.end(JSON.stringify({ error: "Missing alert ID" }));
          return true;
        }

        const now = new Date().toISOString();
        const result = db.execute(
          "UPDATE opc_alerts SET status = 'resolved', resolved_at = ? WHERE id = ? AND status = 'active'",
          now,
          alertId,
        );

        if (result.changes > 0) {
          res.writeHead(200, { "Content-Type": "application/json; charset=utf-8" });
          res.end(JSON.stringify({ ok: true }));
        } else {
          res.writeHead(404, { "Content-Type": "application/json; charset=utf-8" });
          res.end(JSON.stringify({ error: "Alert not found or already resolved" }));
        }
      } catch (err) {
        res.writeHead(500, { "Content-Type": "application/json; charset=utf-8" });
        res.end(JSON.stringify({ error: err instanceof Error ? err.message : String(err) }));
      }
      return true;
    }

    return false;
  };

  const apiAny = api as unknown as {
    registerHttpHandler?: (h: (req: IncomingMessage, res: ServerResponse) => Promise<boolean> | boolean) => void;
    registerHttpRoute?: (r: { path: string; handler: (req: IncomingMessage, res: ServerResponse) => Promise<boolean | void> | boolean | void; auth: string; match?: string }) => void;
  };

  if (typeof apiAny.registerHttpHandler === "function") {
    apiAny.registerHttpHandler(handler);
  } else if (typeof apiAny.registerHttpRoute === "function") {
    apiAny.registerHttpRoute({
      path: "/opc/admin/api",
      handler,
      auth: "plugin",
      match: "prefix",
    });
  }
}

/**
 * 获取 Dashboard 数据
 */
function getDashboardData(db: OpcDatabase): DashboardData {
  const metrics = calculateMetrics(db);
  const alerts = getActiveAlerts(db);
  const todos = getTodayTodos(db);
  const suggestions = generateSuggestions(db, metrics, alerts, todos);

  return {
    metrics,
    alerts,
    todos,
    suggestions,
  };
}

/**
 * 计算关键指标
 */
function calculateMetrics(db: OpcDatabase): DashboardMetrics {
  // 本月收入和支出
  const now = new Date();
  const currentMonthStart = new Date(now.getFullYear(), now.getMonth(), 1).toISOString().slice(0, 10);
  const currentMonthEnd = new Date(now.getFullYear(), now.getMonth() + 1, 0).toISOString().slice(0, 10);

  const currentMonth = db.queryOne(
    `SELECT
      COALESCE(SUM(CASE WHEN type='income' THEN amount ELSE 0 END), 0) as total_income,
      COALESCE(SUM(CASE WHEN type='expense' THEN amount ELSE 0 END), 0) as total_expense
    FROM opc_transactions
    WHERE transaction_date >= ? AND transaction_date <= ?`,
    currentMonthStart,
    currentMonthEnd,
  ) as DashboardRow;

  // 上月收入和支出（用于计算同比）
  const lastMonthStart = new Date(now.getFullYear(), now.getMonth() - 1, 1).toISOString().slice(0, 10);
  const lastMonthEnd = new Date(now.getFullYear(), now.getMonth(), 0).toISOString().slice(0, 10);

  const lastMonth = db.queryOne(
    `SELECT
      COALESCE(SUM(CASE WHEN type='income' THEN amount ELSE 0 END), 0) as total_income,
      COALESCE(SUM(CASE WHEN type='expense' THEN amount ELSE 0 END), 0) as total_expense
    FROM opc_transactions
    WHERE transaction_date >= ? AND transaction_date <= ?`,
    lastMonthStart,
    lastMonthEnd,
  ) as DashboardRow;

  const monthlyIncome = currentMonth.total_income;
  const monthlyExpense = currentMonth.total_expense;
  const monthlyProfit = monthlyIncome - monthlyExpense;

  // 计算同比变化（避免除零）
  const monthlyIncomeChange = lastMonth.total_income > 0
    ? ((monthlyIncome - lastMonth.total_income) / lastMonth.total_income) * 100
    : 0;

  const lastMonthProfit = lastMonth.total_income - lastMonth.total_expense;
  const monthlyProfitChange = lastMonthProfit !== 0
    ? ((monthlyProfit - lastMonthProfit) / Math.abs(lastMonthProfit)) * 100
    : 0;

  // 现金余额（所有收入 - 所有支出）
  const cashBalance = db.queryOne(
    `SELECT
      COALESCE(SUM(CASE WHEN type='income' THEN amount ELSE 0 END), 0) -
      COALESCE(SUM(CASE WHEN type='expense' THEN amount ELSE 0 END), 0) as balance
    FROM opc_transactions`,
  ) as { balance: number };

  // 可撑月数（基于最近3个月平均支出）
  const threeMonthsAgo = new Date(now.getFullYear(), now.getMonth() - 3, 1).toISOString().slice(0, 10);
  const avgExpense = db.queryOne(
    `SELECT COALESCE(AVG(monthly_expense), 0) as avg_expense FROM (
      SELECT SUM(amount) as monthly_expense
      FROM opc_transactions
      WHERE type='expense' AND transaction_date >= ?
      GROUP BY strftime('%Y-%m', transaction_date)
    )`,
    threeMonthsAgo,
  ) as { avg_expense: number };

  const monthsOfRunway = avgExpense.avg_expense > 0
    ? cashBalance.balance / avgExpense.avg_expense
    : 999;

  // 应收账款（未收和部分已收的应收款）
  const receivables = db.queryOne(
    `SELECT COALESCE(SUM(amount - paid_amount), 0) as total
    FROM opc_payments
    WHERE direction = 'receivable' AND status IN ('pending', 'partial')`,
  ) as { total: number };

  // 逾期应收账款
  const today = new Date().toISOString().slice(0, 10);
  const overdueReceivables = db.queryOne(
    `SELECT COALESCE(SUM(amount - paid_amount), 0) as total
    FROM opc_payments
    WHERE direction = 'receivable'
      AND status IN ('pending', 'partial', 'overdue')
      AND due_date < ?`,
    today,
  ) as { total: number };

  return {
    monthlyIncome,
    monthlyIncomeChange,
    monthlyProfit,
    monthlyProfitChange,
    cashBalance: cashBalance.balance,
    monthsOfRunway,
    receivables: receivables.total,
    overdueReceivables: overdueReceivables.total,
  };
}

/**
 * 获取活跃预警
 */
function getActiveAlerts(db: OpcDatabase): DashboardAlert[] {
  const alerts = db.query(
    `SELECT id, company_id, title, severity, category, message, created_at
    FROM opc_alerts
    WHERE status = 'active'
    ORDER BY
      CASE severity
        WHEN 'critical' THEN 0
        WHEN 'warning' THEN 1
        ELSE 2
      END,
      created_at DESC
    LIMIT 10`,
  ) as AlertRow[];

  return alerts.map(alert => ({
    id: alert.id,
    title: alert.title,
    severity: alert.severity as 'critical' | 'warning' | 'info',
    category: alert.category,
    message: alert.message,
    created_at: alert.created_at,
  }));
}

/**
 * 获取今日待办
 */
function getTodayTodos(db: OpcDatabase): DashboardTodo[] {
  const today = new Date().toISOString().slice(0, 10);

  const todos = db.query(
    `SELECT id, company_id, title, priority, related_type as category, due_date, description
    FROM opc_todos
    WHERE status = 'pending'
      AND (due_date = ? OR due_date < ?)
    ORDER BY
      CASE priority
        WHEN 'urgent' THEN 0
        WHEN 'high' THEN 1
        ELSE 2
      END,
      due_date ASC
    LIMIT 20`,
    today,
    today,
  ) as TodoRow[];

  return todos.map(todo => ({
    id: todo.id,
    title: todo.title,
    priority: todo.priority as 'urgent' | 'high' | 'normal',
    category: todo.category || '',
    due_date: todo.due_date || undefined,
    description: todo.description || undefined,
  }));
}

/**
 * 生成 AI 建议
 */
function generateSuggestions(
  db: OpcDatabase,
  metrics: DashboardMetrics,
  alerts: DashboardAlert[],
  todos: DashboardTodo[],
): DashboardSuggestion[] {
  const suggestions: DashboardSuggestion[] = [];

  // 建议1: 现金流预警
  if (metrics.monthsOfRunway < 2) {
    suggestions.push({
      id: "cash-runway-low",
      title: "现金流预警：可撑月数不足",
      description: `当前现金余额 ¥${metrics.cashBalance.toFixed(0)} 仅能维持 ${metrics.monthsOfRunway.toFixed(1)} 个月运营。建议尽快催收应收账款或拓展收入来源。`,
      action: {
        label: "查看应收账款",
        onclick: "loadView('finance')",
      },
    });
  }

  // 建议2: 逾期催收
  if (metrics.overdueReceivables > 0) {
    suggestions.push({
      id: "overdue-receivables",
      title: "逾期账款催收提醒",
      description: `有 ¥${metrics.overdueReceivables.toFixed(0)} 的应收账款已逾期，建议立即联系客户催收。`,
      action: {
        label: "查看逾期清单",
        onclick: "loadView('finance')",
      },
    });
  }

  // 建议3: 利润优化
  if (metrics.monthlyProfit < 0) {
    suggestions.push({
      id: "negative-profit",
      title: "本月利润为负，需优化成本",
      description: `本月支出超过收入 ¥${Math.abs(metrics.monthlyProfit).toFixed(0)}，建议检查支出明细，削减非必要成本。`,
      action: {
        label: "查看支出分析",
        onclick: "loadView('finance')",
      },
    });
  }

  // 建议4: 收入增长策略
  if (metrics.monthlyIncomeChange < -10) {
    suggestions.push({
      id: "income-decline",
      title: "收入下滑，需拓展业务",
      description: `本月收入较上月下降 ${Math.abs(metrics.monthlyIncomeChange).toFixed(1)}%，建议加强客户开发和老客户维护。`,
      action: {
        label: "查看客户管理",
        onclick: "loadView('companies')",
      },
    });
  }

  // 建议5: 合同到期提醒
  const expiringContracts = db.query(
    `SELECT COUNT(*) as cnt FROM opc_contracts
    WHERE status = 'active'
      AND end_date <= date('now', '+30 days')
      AND end_date >= date('now')`,
  ) as { cnt: number }[];

  if (expiringContracts.length > 0 && expiringContracts[0].cnt > 0) {
    suggestions.push({
      id: "contracts-expiring",
      title: "合同即将到期",
      description: `有 ${expiringContracts[0].cnt} 份合同将在 30 天内到期，建议提前联系续约。`,
      action: {
        label: "查看合同列表",
        onclick: "loadView('companies')",
      },
    });
  }

  // 默认建议：一切正常
  if (suggestions.length === 0) {
    suggestions.push({
      id: "all-good",
      title: "经营状况良好",
      description: "当前各项指标正常，继续保持！建议定期回顾财务数据，优化运营效率。",
    });
  }

  return suggestions.slice(0, 5); // 最多返回5条建议
}