package database

import (
	"context"

	"github.com/jackc/pgx/v5/pgxpool"
)

func Migrate(ctx context.Context, pool *pgxpool.Pool) error {
	queries := []string{
		`CREATE TABLE IF NOT EXISTS admins (
			id            SERIAL PRIMARY KEY,
			email         VARCHAR(255) UNIQUE NOT NULL,
			password_hash VARCHAR(255) NOT NULL,
			created_at    TIMESTAMPTZ NOT NULL DEFAULT NOW()
		)`,
		`ALTER TABLE products ADD COLUMN IF NOT EXISTS details TEXT NOT NULL DEFAULT ''`,
		`ALTER TABLE products ADD COLUMN IF NOT EXISTS is_active BOOLEAN NOT NULL DEFAULT true`,
		`ALTER TABLE products ADD COLUMN IF NOT EXISTS updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()`,
		`CREATE TABLE IF NOT EXISTS product_images (
			id          SERIAL PRIMARY KEY,
			product_id  INT NOT NULL REFERENCES products(id) ON DELETE CASCADE,
			file_path   VARCHAR(512) NOT NULL,
			is_primary  BOOLEAN NOT NULL DEFAULT false,
			sort_order  INT NOT NULL DEFAULT 0,
			created_at  TIMESTAMPTZ NOT NULL DEFAULT NOW()
		)`,
		`CREATE INDEX IF NOT EXISTS idx_product_images_product ON product_images (product_id)`,
		`CREATE TABLE IF NOT EXISTS site_stats (
			id           INT PRIMARY KEY DEFAULT 1 CHECK (id = 1),
			total_visits BIGINT NOT NULL DEFAULT 0,
			today_visits INT NOT NULL DEFAULT 0,
			visit_date   DATE NOT NULL DEFAULT CURRENT_DATE
		)`,
		`INSERT INTO site_stats (id) VALUES (1) ON CONFLICT (id) DO NOTHING`,
		`CREATE TABLE IF NOT EXISTS users (
			id SERIAL PRIMARY KEY,
			email VARCHAR(255) UNIQUE NOT NULL,
			password_hash VARCHAR(255) NOT NULL,
			name VARCHAR(255) NOT NULL DEFAULT '',
			phone VARCHAR(50) NOT NULL DEFAULT '',
			address TEXT NOT NULL DEFAULT '',
			created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
		)`,
		`CREATE TABLE IF NOT EXISTS carts (
			id SERIAL PRIMARY KEY,
			user_id INT REFERENCES users(id) ON DELETE CASCADE,
			session_key VARCHAR(64) NOT NULL DEFAULT '',
			updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
		)`,
		`CREATE UNIQUE INDEX IF NOT EXISTS idx_carts_user ON carts (user_id) WHERE user_id IS NOT NULL`,
		`CREATE UNIQUE INDEX IF NOT EXISTS idx_carts_session ON carts (session_key) WHERE user_id IS NULL`,
		`CREATE TABLE IF NOT EXISTS cart_items (
			id SERIAL PRIMARY KEY,
			cart_id INT NOT NULL REFERENCES carts(id) ON DELETE CASCADE,
			product_id INT NOT NULL REFERENCES products(id) ON DELETE CASCADE,
			quantity INT NOT NULL DEFAULT 1 CHECK (quantity > 0),
			UNIQUE (cart_id, product_id)
		)`,
		`CREATE TABLE IF NOT EXISTS orders (
			id SERIAL PRIMARY KEY,
			user_id INT REFERENCES users(id) ON DELETE SET NULL,
			guest_name VARCHAR(255) NOT NULL DEFAULT '',
			guest_email VARCHAR(255) NOT NULL DEFAULT '',
			guest_phone VARCHAR(50) NOT NULL DEFAULT '',
			address TEXT NOT NULL DEFAULT '',
			total NUMERIC(10,2) NOT NULL DEFAULT 0,
			status VARCHAR(50) NOT NULL DEFAULT 'new',
			created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
		)`,
		`CREATE TABLE IF NOT EXISTS order_items (
			id SERIAL PRIMARY KEY,
			order_id INT NOT NULL REFERENCES orders(id) ON DELETE CASCADE,
			product_id INT NOT NULL,
			product_name VARCHAR(255) NOT NULL,
			price NUMERIC(10,2) NOT NULL,
			quantity INT NOT NULL CHECK (quantity > 0)
		)`,
		`CREATE INDEX IF NOT EXISTS idx_orders_user ON orders (user_id)`,
	}

	for _, q := range queries {
		if _, err := pool.Exec(ctx, q); err != nil {
			return err
		}
	}
	return nil
}