-- 切换到目标数据库
\c postgres;

CREATE OR REPLACE FUNCTION update_country_modified_column()
RETURNS TRIGGER AS $$
BEGIN
    NEW.updated_at = CURRENT_TIMESTAMP;
    RETURN NEW;
END;
$$ LANGUAGE plpgsql VOLATILE;

DO $$
BEGIN
    IF NOT EXISTS (SELECT 1 FROM information_schema.tables WHERE table_name = 'country') THEN
        CREATE TABLE "country" (  -- country是关键字，用双引号包裹
            id UUID DEFAULT gen_random_uuid_v7() PRIMARY KEY NOT NULL,
            deleted BOOLEAN NOT NULL DEFAULT FALSE,
            created_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
            updated_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP
        );
        CREATE TRIGGER update_country_updated_at
        BEFORE UPDATE ON "country"
        FOR EACH ROW
        EXECUTE FUNCTION update_country_modified_column();
        
        RAISE NOTICE 'Created country table and trigger';
    ELSE
        RAISE NOTICE 'country table already exists';
    END IF;

    IF NOT EXISTS (SELECT 1 FROM information_schema.tables WHERE table_name = 'name') THEN
        CREATE TABLE name (
            id UUID DEFAULT gen_random_uuid_v7() PRIMARY KEY NOT NULL,
            country_id UUID NOT NULL,
            name VARCHAR NOT NULL,
            deleted BOOLEAN NOT NULL DEFAULT FALSE,
            created_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
            updated_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP
        );
        CREATE TRIGGER update_name_updated_at
        BEFORE UPDATE ON "name"
        FOR EACH ROW
        EXECUTE FUNCTION update_name_modified_column();
        
        RAISE NOTICE 'Created name table and trigger';
    ELSE
        RAISE NOTICE 'name table already exists';
    END IF;

    IF NOT EXISTS (SELECT 1 FROM information_schema.tables WHERE table_name = 'code') THEN
        CREATE TABLE code (
            id UUID DEFAULT gen_random_uuid_v7() PRIMARY KEY NOT NULL,
            country_id UUID NOT NULL,
            code VARCHAR NOT NULL,
            deleted BOOLEAN NOT NULL DEFAULT FALSE,
            created_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP,
            updated_at TIMESTAMPTZ NOT NULL DEFAULT CURRENT_TIMESTAMP
        );
        CREATE TRIGGER update_code_updated_at
        BEFORE UPDATE ON "code"
        FOR EACH ROW
        EXECUTE FUNCTION update_code_modified_column();
        
        RAISE NOTICE 'Created code table and trigger';
    ELSE
        RAISE NOTICE 'code table already exists';
    END IF;
END $$;

DO $$
DECLARE
    view_exists BOOLEAN;
BEGIN
    -- 检查视图是否已存在
    SELECT EXISTS (
        SELECT 1 FROM information_schema.views 
        WHERE table_name = 'country_info_view'
    ) INTO view_exists;

    -- 创建或更新视图
    CREATE OR REPLACE VIEW country_info_view AS
    SELECT 
        u.id AS country_id,
        n.name AS name,
        c.code AS code,
        u.deleted AS deleted
    FROM 
        "country" u
    JOIN 
        name n ON u.id = n.country_id
    JOIN 
        code c ON u.id = c.country_id
    WHERE
        u.deleted = FALSE;

    -- 根据视图是否已存在输出不同提示
    IF view_exists THEN
        RAISE NOTICE '视图 country_info_view 已更新';
    ELSE
        RAISE NOTICE '视图 country_info_view 已创建';
    END IF;
EXCEPTION
    WHEN OTHERS THEN
        RAISE NOTICE '处理视图时发生错误: %', SQLERRM;
END $$;