// Copyright 2024 CloudWeGo Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package model

import (
	"context"
	"encoding/json"
	"fmt"
	"time"

	"github.com/redis/go-redis/v9"
	"gorm.io/gorm"
)

type Product struct {
	Base
	Name        string     `json:"name"`
	Description string     `json:"description"`
	Picture     string     `json:"picture"`
	Price       float32    `json:"price"`
	Categories  []Category `json:"categories" gorm:"many2many:product_category"`
}

func (p Product) TableName() string {
	return "product"
}

type ProductQuery struct {
	ctx context.Context
	db  *gorm.DB
}

func (p ProductQuery) GetById(productId int) (product Product, err error) {
	err = p.db.WithContext(p.ctx).Model(&Product{}).Where(&Product{Base: Base{ID: productId}}).First(&product).Error
	return
}

func NewProductQuery(ctx context.Context, db *gorm.DB) ProductQuery {
	return ProductQuery{ctx: ctx, db: db}
}

type CachedProductQuery struct {
	productQuery ProductQuery
	cacheClient  *redis.Client
	prefix       string
}

func (c CachedProductQuery) GetById(productId int) (product Product, err error) {
	cacheKey := fmt.Sprintf("%s_%s_%d", c.prefix, "product_by_id", productId)
	cachedResult := c.cacheClient.Get(c.productQuery.ctx, cacheKey)

	err = func() error {
		err1 := cachedResult.Err()
		if err1 != nil {
			return err1
		}
		cachedResultByte, err2 := cachedResult.Bytes()
		if err2 != nil {
			return err2
		}
		err3 := json.Unmarshal(cachedResultByte, &product)
		if err3 != nil {
			return err3
		}
		return nil
	}()

	if err != nil {
		product, err = c.productQuery.GetById(productId)
		if err != nil {
			return Product{}, err
		}
		encoded, err := json.Marshal(product)
		if err != nil {
			return product, nil
		}
		_ = c.cacheClient.Set(c.productQuery.ctx, cacheKey, encoded, time.Hour)
	}
	return
}

func NewCachedProductQuery(pq ProductQuery, cacheClient *redis.Client) CachedProductQuery {
	return CachedProductQuery{productQuery: pq, cacheClient: cacheClient, prefix: "cloudwego_shop"}
}

func GetProductById(db *gorm.DB, ctx context.Context, productId int) (product Product, err error) {
	err = db.WithContext(ctx).Model(&Product{}).Where(&Product{Base: Base{ID: productId}}).First(&product).Error
	return product, err
}

func SearchProduct(db *gorm.DB, ctx context.Context, q string) (product []*Product, err error) {
	err = db.WithContext(ctx).Model(&Product{}).Find(&product, "name like ? or description like ?", "%"+q+"%", "%"+q+"%").Error
	return product, err
}
