-- ====================================================================
-- 角色字段统一说明
-- ====================================================================
-- 注意：角色信息统一存储在 ak_users.role 字段中
-- ml_user_profiles 表不再包含 role 字段，避免数据重复
-- 本脚本主要用于清理可能存在的重复字段和更新相关函数
-- ====================================================================

\echo '检查角色字段统一状态...'

BEGIN;

-- ====================================================================
-- 1. 安全检查
-- ====================================================================

-- 检查表是否存在
DO $$
BEGIN
    IF NOT EXISTS (SELECT 1 FROM information_schema.tables WHERE table_name = 'ml_user_profiles') THEN
        RAISE EXCEPTION '表 ml_user_profiles 不存在，请先运行完整数据库创建脚本';
    END IF;
END $$;

-- 检查是否已经有 role 字段
DO $$
BEGIN
    IF EXISTS (SELECT 1 FROM information_schema.columns WHERE table_name = 'ml_user_profiles' AND column_name = 'role') THEN
        RAISE NOTICE '检测到 role 字段已存在，跳过字段创建';
    ELSE
        RAISE NOTICE '开始添加 role 字段';
        -- 添加 role 字段
        ALTER TABLE public.ml_user_profiles 
        ADD COLUMN role TEXT DEFAULT 'customer';
    END IF;
END $$;

-- ====================================================================
-- 2. 数据迁移
-- ====================================================================

-- 迁移现有 user_type 数据到 role 字段
UPDATE public.ml_user_profiles 
SET role = CASE 
    WHEN user_type = 1 THEN 'customer'     -- 消费者
    WHEN user_type = 2 THEN 'merchant'     -- 商家
    WHEN user_type = 3 THEN 'delivery'     -- 配送员
    WHEN user_type = 4 THEN 'service'      -- 客服
    WHEN user_type = 5 THEN 'admin'        -- 管理员
    ELSE 'customer'
END
WHERE role = 'customer' OR role IS NULL;

-- 设置非空约束
ALTER TABLE public.ml_user_profiles 
ALTER COLUMN role SET NOT NULL;

-- ====================================================================
-- 3. 约束和索引更新
-- ====================================================================

-- 添加新的约束
DO $$
BEGIN
    IF NOT EXISTS (SELECT 1 FROM information_schema.check_constraints WHERE constraint_name = 'chk_ml_user_role') THEN
        ALTER TABLE public.ml_user_profiles 
        ADD CONSTRAINT chk_ml_user_role 
        CHECK (role IN ('customer', 'merchant', 'delivery', 'service', 'admin'));
        RAISE NOTICE '已添加 role 字段约束';
    END IF;
END $$;

-- 创建新索引
DROP INDEX IF EXISTS idx_ml_user_profiles_role;
CREATE INDEX idx_ml_user_profiles_role ON public.ml_user_profiles(role);

-- ====================================================================
-- 4. 同步 ak_users 表的 role 字段
-- ====================================================================

-- 同步 ak_users.role 字段
UPDATE public.ak_users 
SET role = p.role,
    updated_at = CURRENT_TIMESTAMP
FROM public.ml_user_profiles p
WHERE ak_users.id = p.user_id
AND (ak_users.role != p.role OR ak_users.role IS NULL);

-- ====================================================================
-- 5. 更新函数和视图
-- ====================================================================

-- 更新商家验证函数
CREATE OR REPLACE FUNCTION public.is_verified_merchant(user_uuid UUID)
RETURNS BOOLEAN
LANGUAGE plpgsql
SECURITY DEFINER
AS $$
DECLARE
    result BOOLEAN := FALSE;
BEGIN
    SELECT (role = 'merchant' AND verification_status = 1) INTO result
    FROM public.ml_user_profiles
    WHERE user_id = user_uuid;
    
    RETURN COALESCE(result, FALSE);
END;
$$;

-- 更新用户信息视图
CREATE OR REPLACE VIEW public.ml_users_view AS
SELECT 
    u.id,
    u.email,
    u.username,
    u.phone,
    u.avatar_url,
    u.status as user_status,
    u.gender,
    u.birthday,
    u.bio,
    u.created_at as user_created_at,
    u.updated_at as user_updated_at,
    p.role,
    p.status,
    p.real_name,
    p.credit_score,
    p.verification_status,
    p.created_at as profile_created_at,
    p.updated_at as profile_updated_at,
    CASE 
        WHEN p.role = 'customer' THEN '消费者'
        WHEN p.role = 'merchant' THEN '商家'
        WHEN p.role = 'delivery' THEN '配送员'
        WHEN p.role = 'service' THEN '客服'
        WHEN p.role = 'admin' THEN '管理员'
        ELSE '未知'
    END as role_name
FROM public.ak_users u
LEFT JOIN public.ml_user_profiles p ON u.id = p.user_id;

-- ====================================================================
-- 6. 更新字段注释
-- ====================================================================

COMMENT ON COLUMN public.ml_user_profiles.role IS '用户角色：customer消费者, merchant商家, delivery配送员, service客服, admin管理员';

-- ====================================================================
-- 7. 验证迁移结果
-- ====================================================================

DO $$
DECLARE
    total_users INTEGER;
    migrated_users INTEGER;
    role_stats RECORD;
BEGIN
    -- 统计总用户数
    SELECT COUNT(*) INTO total_users FROM public.ml_user_profiles;
    
    -- 统计已迁移用户数
    SELECT COUNT(*) INTO migrated_users 
    FROM public.ml_user_profiles 
    WHERE role IN ('customer', 'merchant', 'delivery', 'service', 'admin');
    
    RAISE NOTICE '迁移完成：总用户 %, 已迁移 %', total_users, migrated_users;
    
    -- 显示角色分布
    RAISE NOTICE '角色分布统计：';
    FOR role_stats IN 
        SELECT role, COUNT(*) as count
        FROM public.ml_user_profiles
        GROUP BY role
        ORDER BY count DESC
    LOOP
        RAISE NOTICE '  %: % 用户', role_stats.role, role_stats.count;
    END LOOP;
END $$;

COMMIT;

\echo '角色字段迁移完成！'

-- ====================================================================
-- 8. 可选：清理旧字段（请谨慎执行）
-- ====================================================================

/*
-- 警告：以下操作将永久删除 user_type 字段，请确保迁移成功后再执行

BEGIN;

-- 删除旧约束
ALTER TABLE public.ml_user_profiles DROP CONSTRAINT IF EXISTS chk_ml_user_type;

-- 删除旧索引
DROP INDEX IF EXISTS idx_ml_user_profiles_type;

-- 删除旧字段
ALTER TABLE public.ml_user_profiles DROP COLUMN IF EXISTS user_type;

COMMIT;

\echo '旧 user_type 字段清理完成';
*/

-- ====================================================================
-- 9. 回滚脚本（如需回滚，请执行以下命令）
-- ====================================================================

/*
-- 回滚到 user_type 字段（仅在必要时执行）

BEGIN;

-- 重新添加 user_type 字段
ALTER TABLE public.ml_user_profiles 
ADD COLUMN user_type INTEGER DEFAULT 1;

-- 从 role 字段恢复数据
UPDATE public.ml_user_profiles 
SET user_type = CASE 
    WHEN role = 'customer' THEN 1
    WHEN role = 'merchant' THEN 2
    WHEN role = 'delivery' THEN 3
    WHEN role = 'service' THEN 4
    WHEN role = 'admin' THEN 5
    ELSE 1
END;

-- 设置非空约束
ALTER TABLE public.ml_user_profiles 
ALTER COLUMN user_type SET NOT NULL;

-- 重新添加约束
ALTER TABLE public.ml_user_profiles 
ADD CONSTRAINT chk_ml_user_type CHECK (user_type IN (1,2,3,4,5));

-- 重新创建索引
CREATE INDEX idx_ml_user_profiles_type ON public.ml_user_profiles(user_type);

-- 删除 role 字段
ALTER TABLE public.ml_user_profiles DROP CONSTRAINT IF EXISTS chk_ml_user_role;
ALTER TABLE public.ml_user_profiles DROP COLUMN IF EXISTS role;

COMMIT;

\echo '已回滚到 user_type 字段';
*/