-- =============================================
-- 配送效率分析 - 配送相关基础表（建表 + 升级，支持重复执行）
-- 说明：
-- - 本脚本用于测试阶段，为配送效率分析页面提供必要的表结构。
-- - 使用 CREATE TABLE IF NOT EXISTS + DO 块判断列/约束是否存在，实现可重复执行。
-- - 外键：
--   - driver_id -> ml_delivery_drivers(id) 必须存在。
--   - user_id -> ak_users(id) 仅在 ak_users 表存在时才会创建外键（避免执行报错）。
-- =============================================

-- 1) 创建基础表（若不存在）
CREATE TABLE IF NOT EXISTS public.ml_delivery_drivers (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  real_name TEXT,
  created_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS public.ml_delivery_tasks (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  created_at TIMESTAMPTZ DEFAULT NOW()
);

-- 2) 补齐字段（若不存在）
DO $$
BEGIN
  -- =========================
  -- ml_delivery_drivers
  -- =========================
  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_drivers' AND column_name='user_id'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers ADD COLUMN user_id UUID;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_drivers' AND column_name='work_status'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers ADD COLUMN work_status INTEGER DEFAULT 1;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_drivers' AND column_name='rating_avg'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers ADD COLUMN rating_avg NUMERIC(3,2) DEFAULT 0;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_drivers' AND column_name='rating_count'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers ADD COLUMN rating_count INTEGER DEFAULT 0;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_drivers' AND column_name='updated_at'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers ADD COLUMN updated_at TIMESTAMPTZ DEFAULT NOW();
  END IF;

  -- =========================
  -- ml_delivery_tasks
  -- =========================
  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_tasks' AND column_name='order_id'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks ADD COLUMN order_id UUID;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_tasks' AND column_name='driver_id'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks ADD COLUMN driver_id UUID;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_tasks' AND column_name='status'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks ADD COLUMN status INTEGER DEFAULT 1;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_tasks' AND column_name='assigned_at'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks ADD COLUMN assigned_at TIMESTAMPTZ;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_tasks' AND column_name='delivered_at'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks ADD COLUMN delivered_at TIMESTAMPTZ;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_tasks' AND column_name='delivery_fee'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks ADD COLUMN delivery_fee NUMERIC(10,2) DEFAULT 0;
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema='public' AND table_name='ml_delivery_tasks' AND column_name='updated_at'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks ADD COLUMN updated_at TIMESTAMPTZ DEFAULT NOW();
  END IF;
END;
$$;

-- 3) 添加表/字段中文注释
COMMENT ON TABLE public.ml_delivery_drivers IS '配送员表';
COMMENT ON COLUMN public.ml_delivery_drivers.id IS '配送员ID';
COMMENT ON COLUMN public.ml_delivery_drivers.user_id IS '关联用户ID（可选，若存在 ak_users 表则可建立外键）';
COMMENT ON COLUMN public.ml_delivery_drivers.real_name IS '真实姓名';
COMMENT ON COLUMN public.ml_delivery_drivers.work_status IS '工作状态：1在线 2忙碌 3离线';
COMMENT ON COLUMN public.ml_delivery_drivers.rating_avg IS '平均评分（0-5）';
COMMENT ON COLUMN public.ml_delivery_drivers.rating_count IS '评分次数';
COMMENT ON COLUMN public.ml_delivery_drivers.created_at IS '创建时间';
COMMENT ON COLUMN public.ml_delivery_drivers.updated_at IS '更新时间';

COMMENT ON TABLE public.ml_delivery_tasks IS '配送任务表（接单->送达）';
COMMENT ON COLUMN public.ml_delivery_tasks.id IS '任务ID';
COMMENT ON COLUMN public.ml_delivery_tasks.order_id IS '订单ID（测试阶段可空；正式可做 UNIQUE + 外键）';
COMMENT ON COLUMN public.ml_delivery_tasks.driver_id IS '配送员ID';
COMMENT ON COLUMN public.ml_delivery_tasks.status IS '状态：1待接 2已接 3取货 4配送中 5已送达 6配送失败';
COMMENT ON COLUMN public.ml_delivery_tasks.assigned_at IS '接单时间';
COMMENT ON COLUMN public.ml_delivery_tasks.delivered_at IS '送达时间';
COMMENT ON COLUMN public.ml_delivery_tasks.delivery_fee IS '配送费';
COMMENT ON COLUMN public.ml_delivery_tasks.created_at IS '创建时间';
COMMENT ON COLUMN public.ml_delivery_tasks.updated_at IS '更新时间';

-- 4) 添加约束（幂等）
DO $$
BEGIN
  -- drivers: real_name 唯一
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='u' AND n.nspname='public' AND t.relname='ml_delivery_drivers' AND c.conname='ml_delivery_drivers_real_name_key'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers
      ADD CONSTRAINT ml_delivery_drivers_real_name_key UNIQUE (real_name);
  END IF;

  -- drivers: work_status 枚举
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='c' AND n.nspname='public' AND t.relname='ml_delivery_drivers' AND c.conname='chk_ml_delivery_drivers_work_status'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers
      ADD CONSTRAINT chk_ml_delivery_drivers_work_status CHECK (work_status IN (1,2,3));
  END IF;

  -- drivers: rating_avg 范围
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='c' AND n.nspname='public' AND t.relname='ml_delivery_drivers' AND c.conname='chk_ml_delivery_drivers_rating_avg'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers
      ADD CONSTRAINT chk_ml_delivery_drivers_rating_avg CHECK (rating_avg >= 0 AND rating_avg <= 5);
  END IF;

  -- drivers: rating_count 非负
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='c' AND n.nspname='public' AND t.relname='ml_delivery_drivers' AND c.conname='chk_ml_delivery_drivers_rating_count'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers
      ADD CONSTRAINT chk_ml_delivery_drivers_rating_count CHECK (rating_count >= 0);
  END IF;

  -- tasks: status 枚举
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='c' AND n.nspname='public' AND t.relname='ml_delivery_tasks' AND c.conname='chk_ml_delivery_tasks_status'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks
      ADD CONSTRAINT chk_ml_delivery_tasks_status CHECK (status IN (1,2,3,4,5,6));
  END IF;

  -- tasks: delivery_fee 非负
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='c' AND n.nspname='public' AND t.relname='ml_delivery_tasks' AND c.conname='chk_ml_delivery_tasks_delivery_fee'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks
      ADD CONSTRAINT chk_ml_delivery_tasks_delivery_fee CHECK (delivery_fee >= 0);
  END IF;

  -- tasks: 时间逻辑 delivered_at >= assigned_at
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='c' AND n.nspname='public' AND t.relname='ml_delivery_tasks' AND c.conname='chk_ml_delivery_tasks_time_logic'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks
      ADD CONSTRAINT chk_ml_delivery_tasks_time_logic CHECK (
        delivered_at IS NULL OR assigned_at IS NULL OR delivered_at >= assigned_at
      );
  END IF;

  -- tasks: driver_id 外键
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='f' AND n.nspname='public' AND t.relname='ml_delivery_tasks' AND c.conname='ml_delivery_tasks_driver_id_fkey'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks
      ADD CONSTRAINT ml_delivery_tasks_driver_id_fkey FOREIGN KEY (driver_id)
      REFERENCES public.ml_delivery_drivers(id) ON DELETE SET NULL;
  END IF;

  -- drivers: user_id 外键（仅当 ak_users 表存在时才创建）
  IF EXISTS (
    SELECT 1 FROM information_schema.tables
    WHERE table_schema='public' AND table_name='ak_users'
  ) THEN
    IF NOT EXISTS (
      SELECT 1 FROM pg_constraint c
      JOIN pg_class t ON t.oid = c.conrelid
      JOIN pg_namespace n ON n.oid = t.relnamespace
      WHERE c.contype='f' AND n.nspname='public' AND t.relname='ml_delivery_drivers' AND c.conname='ml_delivery_drivers_user_id_fkey'
    ) THEN
      ALTER TABLE public.ml_delivery_drivers
        ADD CONSTRAINT ml_delivery_drivers_user_id_fkey FOREIGN KEY (user_id)
        REFERENCES public.ak_users(id) ON DELETE SET NULL;
    END IF;
  END IF;

  -- drivers: user_id 唯一（如果你不用 user_id，可以后续删除该约束）
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='u' AND n.nspname='public' AND t.relname='ml_delivery_drivers' AND c.conname='ml_delivery_drivers_user_id_key'
  ) THEN
    ALTER TABLE public.ml_delivery_drivers
      ADD CONSTRAINT ml_delivery_drivers_user_id_key UNIQUE (user_id);
  END IF;

  -- tasks: order_id 唯一（测试阶段允许 NULL，NULL 不冲突）
  IF NOT EXISTS (
    SELECT 1 FROM pg_constraint c
    JOIN pg_class t ON t.oid = c.conrelid
    JOIN pg_namespace n ON n.oid = t.relnamespace
    WHERE c.contype='u' AND n.nspname='public' AND t.relname='ml_delivery_tasks' AND c.conname='ml_delivery_tasks_order_id_key'
  ) THEN
    ALTER TABLE public.ml_delivery_tasks
      ADD CONSTRAINT ml_delivery_tasks_order_id_key UNIQUE (order_id);
  END IF;

END;
$$;

-- 5) 索引（幂等）
CREATE INDEX IF NOT EXISTS idx_ml_delivery_drivers_work_status ON public.ml_delivery_drivers(work_status);
CREATE INDEX IF NOT EXISTS idx_ml_delivery_tasks_status ON public.ml_delivery_tasks(status);
CREATE INDEX IF NOT EXISTS idx_ml_delivery_tasks_assigned_at ON public.ml_delivery_tasks(assigned_at);
CREATE INDEX IF NOT EXISTS idx_ml_delivery_tasks_driver_id ON public.ml_delivery_tasks(driver_id);

-- 完成
SELECT 'delivery tables ensured' AS message;