-- ✅ 创建 schema （幂等）
DO $$
BEGIN
    IF NOT EXISTS (
        SELECT schema_name FROM information_schema.schemata
        WHERE schema_name = 'storage'
    ) THEN
        CREATE SCHEMA storage;
    END IF;
END$$;

-- ✅ 创建角色和默认权限（幂等）
DO $$
DECLARE
    install_roles text := COALESCE(current_setting('storage.install_roles', true), 'true');
    anon_role text := COALESCE(current_setting('storage.anon_role', true), 'anon');
    authenticated_role text := COALESCE(current_setting('storage.authenticated_role', true), 'authenticated');
    service_role text := COALESCE(current_setting('storage.service_role', true), 'service_role');
BEGIN
    IF install_roles != 'true' THEN RETURN; END IF;

    IF NOT EXISTS (SELECT 1 FROM pg_roles WHERE rolname = anon_role) THEN
        EXECUTE 'CREATE ROLE ' || quote_ident(anon_role) || ' NOLOGIN NOINHERIT';
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_roles WHERE rolname = authenticated_role) THEN
        EXECUTE 'CREATE ROLE ' || quote_ident(authenticated_role) || ' NOLOGIN NOINHERIT';
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_roles WHERE rolname = service_role) THEN
        EXECUTE 'CREATE ROLE ' || quote_ident(service_role) || ' NOLOGIN NOINHERIT BYPASSRLS';
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_roles WHERE rolname = 'authenticator') THEN
        CREATE USER authenticator NOINHERIT;
    END IF;

    EXECUTE 'GRANT ' || quote_ident(anon_role) || ',' ||
                     quote_ident(authenticated_role) || ',' ||
                     quote_ident(service_role) || ' TO authenticator';

    EXECUTE 'GRANT USAGE ON SCHEMA storage TO ' ||
        quote_ident(anon_role) || ',' ||
        quote_ident(authenticated_role) || ',' ||
        quote_ident(service_role);

    EXECUTE 'ALTER DEFAULT PRIVILEGES IN SCHEMA storage GRANT ALL ON TABLES TO ' ||
        quote_ident(anon_role) || ',' || quote_ident(authenticated_role) || ',' || quote_ident(service_role);
    EXECUTE 'ALTER DEFAULT PRIVILEGES IN SCHEMA storage GRANT ALL ON FUNCTIONS TO ' ||
        quote_ident(anon_role) || ',' || quote_ident(authenticated_role) || ',' || quote_ident(service_role);
    EXECUTE 'ALTER DEFAULT PRIVILEGES IN SCHEMA storage GRANT ALL ON SEQUENCES TO ' ||
        quote_ident(anon_role) || ',' || quote_ident(authenticated_role) || ',' || quote_ident(service_role);
END$$;

-- ✅ 创建 migrations 表（幂等）
CREATE TABLE IF NOT EXISTS storage.migrations (
  id integer PRIMARY KEY,
  name varchar(100) UNIQUE NOT NULL,
  hash varchar(40) NOT NULL,
  executed_at timestamp DEFAULT current_timestamp
);

-- ✅ 创建 buckets 表（不含 public 字段）
CREATE TABLE IF NOT EXISTS storage.buckets (
    id text NOT NULL,
    name text NOT NULL,
    owner uuid,
    created_at timestamptz DEFAULT now(),
    updated_at timestamptz DEFAULT now(),
    PRIMARY KEY (id)
);
CREATE UNIQUE INDEX IF NOT EXISTS bname ON storage.buckets (name);

-- ✅ 补 public 字段（兼容升级）
DO $$
BEGIN
  IF NOT EXISTS (
    SELECT 1 FROM information_schema.columns
    WHERE table_schema = 'storage'
      AND table_name = 'buckets'
      AND column_name = 'public'
  ) THEN
    ALTER TABLE storage.buckets
    ADD COLUMN public boolean NOT NULL DEFAULT false;
  END IF;
END$$;

-- ✅ 创建 objects 表
CREATE TABLE IF NOT EXISTS storage.objects (
    id uuid NOT NULL DEFAULT gen_random_uuid(),
    bucket_id text,
    name text,
    owner uuid,
    created_at timestamptz DEFAULT now(),
    updated_at timestamptz DEFAULT now(),
    last_accessed_at timestamptz DEFAULT now(),
    metadata jsonb,
    CONSTRAINT objects_bucketId_fkey FOREIGN KEY (bucket_id) REFERENCES storage.buckets(id),
    PRIMARY KEY (id)
);
CREATE UNIQUE INDEX IF NOT EXISTS bucketid_objname ON storage.objects (bucket_id, name);
CREATE INDEX IF NOT EXISTS name_prefix_search ON storage.objects (name text_pattern_ops);

-- ✅ 启用 RLS
ALTER TABLE storage.objects ENABLE ROW LEVEL SECURITY;

-- ✅ 内置函数（可重用）
CREATE OR REPLACE FUNCTION storage.foldername(name text)
 RETURNS text[] LANGUAGE plpgsql AS $$
DECLARE _parts text[];
BEGIN
	SELECT string_to_array(name, '/') INTO _parts;
	RETURN _parts[1:array_length(_parts,1)-1];
END$$;

CREATE OR REPLACE FUNCTION storage.filename(name text)
 RETURNS text LANGUAGE plpgsql AS $$
DECLARE _parts text[];
BEGIN
	SELECT string_to_array(name, '/') INTO _parts;
	RETURN _parts[array_length(_parts,1)];
END$$;

CREATE OR REPLACE FUNCTION storage.extension(name text)
 RETURNS text LANGUAGE plpgsql AS $$
DECLARE _parts text[]; _filename text;
BEGIN
	SELECT string_to_array(name, '/') INTO _parts;
	SELECT _parts[array_length(_parts,1)] INTO _filename;
	RETURN reverse(split_part(reverse(_filename), '.', 1));
END$$;

-- ✅ 文件夹搜索函数（用于前端分层目录浏览）
CREATE OR REPLACE FUNCTION storage.search(
  prefix text, bucketname text, limits int DEFAULT 100, levels int DEFAULT 1, offsets int DEFAULT 0
)
 RETURNS TABLE (
    name text,
    id uuid,
    updated_at timestamptz,
    created_at timestamptz,
    last_accessed_at timestamptz,
    metadata jsonb
 )
 LANGUAGE plpgsql AS $$
BEGIN
	RETURN QUERY
	WITH files_folders AS (
		SELECT (string_to_array(objects.name, '/'))[levels] AS folder
		FROM storage.objects
		WHERE objects.name ILIKE prefix || '%'
		  AND bucket_id = bucketname
		GROUP BY folder
		LIMIT limits OFFSET offsets
	)
	SELECT
		files_folders.folder AS name,
		objects.id,
		objects.updated_at,
		objects.created_at,
		objects.last_accessed_at,
		objects.metadata
	FROM files_folders
	LEFT JOIN storage.objects
	ON prefix || files_folders.folder = objects.name
	   AND objects.bucket_id = bucketname;
END$$;

-- ✅ 管理员角色创建（幂等）
DO $$
DECLARE
    install_roles text := COALESCE(current_setting('storage.install_roles', true), 'true');
    super_user text := COALESCE(current_setting('storage.super_user', true), 'supabase_storage_admin');
BEGIN
    IF install_roles != 'true' THEN RETURN; END IF;

    IF NOT EXISTS (SELECT 1 FROM pg_roles WHERE rolname = super_user) THEN
        EXECUTE 'CREATE ROLE ' || quote_ident(super_user) || ' NOINHERIT CREATEROLE LOGIN NOREPLICATION';
    END IF;

    EXECUTE 'GRANT ALL PRIVILEGES ON SCHEMA storage TO ' || quote_ident(super_user);
    EXECUTE 'GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA storage TO ' || quote_ident(super_user);
    EXECUTE 'GRANT ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA storage TO ' || quote_ident(super_user);

    IF super_user != 'postgres' THEN
        EXECUTE 'ALTER ROLE ' || quote_ident(super_user) || ' SET search_path = "storage"';
    END IF;

    EXECUTE 'ALTER TABLE storage.objects OWNER TO ' || quote_ident(super_user);
    EXECUTE 'ALTER TABLE storage.buckets OWNER TO ' || quote_ident(super_user);
    EXECUTE 'ALTER TABLE storage.migrations OWNER TO ' || quote_ident(super_user);

    EXECUTE 'ALTER FUNCTION storage.foldername(text) OWNER TO ' || quote_ident(super_user);
    EXECUTE 'ALTER FUNCTION storage.filename(text) OWNER TO ' || quote_ident(super_user);
    EXECUTE 'ALTER FUNCTION storage.extension(text) OWNER TO ' || quote_ident(super_user);
    EXECUTE 'ALTER FUNCTION storage.search(text,text,int,int,int) OWNER TO ' || quote_ident(super_user);
END$$;

-- ✅ 插入默认 bucket（公开访问，用于头像）
INSERT INTO storage.buckets (id, name, owner, public)
VALUES ('profile_images', 'profile_images', NULL, true)
ON CONFLICT (id) DO UPDATE SET public = true;

-- ✅ RLS 策略定义（幂等）
DO $$
BEGIN
  IF NOT EXISTS (
    SELECT 1 FROM pg_policies WHERE policyname = 'anon upload profile_images'
  ) THEN
    EXECUTE 'CREATE POLICY "anon upload profile_images"
             ON storage.objects
             FOR INSERT
             TO anon
             WITH CHECK (bucket_id = ''profile_images'')';
  END IF;

  IF NOT EXISTS (
    SELECT 1 FROM pg_policies WHERE policyname = 'anon read profile_images'
  ) THEN
    EXECUTE 'CREATE POLICY "anon read profile_images"
             ON storage.objects
             FOR SELECT
             TO anon
             USING (bucket_id = ''profile_images'')';
  END IF;
END$$;
