package cache

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

	"github.com/luxsin/app-api/internal/model"
	"github.com/redis/go-redis/v9"
)

const (
	modelBrandPrefix = "model:brand:"
	modelAllKey      = "model:all"
	modelTTL         = 30 * time.Minute
)

type ModelCache struct {
	rdb *redis.Client
}

func NewModelCache(rdb *redis.Client) *ModelCache {
	return &ModelCache{rdb: rdb}
}

func (c *ModelCache) Exists(ctx context.Context) (bool, error) {
	n, err := c.rdb.Exists(ctx, modelAllKey).Result()
	if err != nil {
		return false, err
	}
	return n > 0, nil
}

func modelBrandKey(brandName string) string {
	return modelBrandPrefix + brandName
}

func (c *ModelCache) GetByBrand(ctx context.Context, brandName string) ([]model.Model, error) {
	data, err := c.rdb.Get(ctx, modelBrandKey(brandName)).Bytes()
	if err != nil {
		return nil, err
	}
	var list []model.Model
	if err := json.Unmarshal(data, &list); err != nil {
		return nil, fmt.Errorf("unmarshal models: %w", err)
	}
	return list, nil
}

func (c *ModelCache) SetByBrand(ctx context.Context, brandName string, list []model.Model) error {
	data, err := json.Marshal(list)
	if err != nil {
		return fmt.Errorf("marshal models: %w", err)
	}
	return c.rdb.Set(ctx, modelBrandKey(brandName), data, modelTTL).Err()
}

func (c *ModelCache) GetAll(ctx context.Context) ([]model.Model, error) {
	data, err := c.rdb.Get(ctx, modelAllKey).Bytes()
	if err != nil {
		return nil, err
	}
	var list []model.Model
	if err := json.Unmarshal(data, &list); err != nil {
		return nil, fmt.Errorf("unmarshal models: %w", err)
	}
	return list, nil
}

func (c *ModelCache) SetAll(ctx context.Context, list []model.Model) error {
	data, err := json.Marshal(list)
	if err != nil {
		return fmt.Errorf("marshal models: %w", err)
	}
	return c.rdb.Set(ctx, modelAllKey, data, modelTTL).Err()
}