package oss

import (
	"encoding/json"
	"io"
	"log"
	"net/url"
	"strings"

	"soul-api/internal/database"
	"soul-api/internal/model"

	alioss "github.com/aliyun/aliyun-oss-go-sdk/oss"
)

// Config 阿里云 OSS 配置，与管理端 ossConfig 字段对应
type Config struct {
	Endpoint        string `json:"endpoint"`
	Bucket          string `json:"bucket"`
	Region          string `json:"region"`
	AccessKeyID     string `json:"accessKeyId"`
	AccessKeySecret string `json:"accessKeySecret"`
}

// LoadConfig 从 system_config 读取 oss_config，配置不完整时返回 nil
func LoadConfig() *Config {
	var row model.SystemConfig
	if err := database.DB().Where("config_key = ?", "oss_config").First(&row).Error; err != nil {
		return nil
	}
	var m map[string]interface{}
	if err := json.Unmarshal(row.ConfigValue, &m); err != nil {
		return nil
	}
	var cfg Config
	if v, ok := m["endpoint"].(string); ok && v != "" {
		cfg.Endpoint = strings.TrimSpace(v)
	}
	if v, ok := m["bucket"].(string); ok && v != "" {
		cfg.Bucket = strings.TrimSpace(v)
	}
	if v, ok := m["accessKeyId"].(string); ok && v != "" {
		cfg.AccessKeyID = v
	}
	if v, ok := m["accessKeySecret"].(string); ok && v != "" {
		cfg.AccessKeySecret = v
	}
	if cfg.Endpoint == "" || cfg.Bucket == "" || cfg.AccessKeyID == "" || cfg.AccessKeySecret == "" {
		return nil
	}
	// endpoint 去掉 scheme，SDK 需要
	cfg.Endpoint = strings.TrimPrefix(strings.TrimPrefix(cfg.Endpoint, "https://"), "http://")
	return &cfg
}

// IsEnabled 是否已配置 OSS 且可用
func IsEnabled() bool {
	return LoadConfig() != nil
}

// Upload 上传文件到 OSS，objectKey 如 "uploads/avatars/xxx.jpg"
// 返回公网访问 URL，如 https://bucket.oss-cn-hangzhou.aliyuncs.com/uploads/avatars/xxx.jpg
func Upload(objectKey string, reader io.Reader, options ...alioss.Option) (string, error) {
	cfg := LoadConfig()
	if cfg == nil {
		return "", nil // 未配置，调用方需回退本地
	}
	client, err := alioss.New(cfg.Endpoint, cfg.AccessKeyID, cfg.AccessKeySecret)
	if err != nil {
		log.Printf("oss: client init failed: %v", err)
		return "", err
	}
	bucket, err := client.Bucket(cfg.Bucket)
	if err != nil {
		log.Printf("oss: bucket %s failed: %v", cfg.Bucket, err)
		return "", err
	}
	if err := bucket.PutObject(objectKey, reader, options...); err != nil {
		log.Printf("oss: PutObject %s failed: %v", objectKey, err)
		return "", err
	}
	// 公网 URL：https://{bucket}.{endpoint}/{objectKey}
	u := "https://" + cfg.Bucket + "." + cfg.Endpoint + "/" + objectKey
	return u, nil
}

// Delete 从 OSS 删除对象，objectKey 如 "uploads/avatars/xxx.jpg"
func Delete(objectKey string) error {
	cfg := LoadConfig()
	if cfg == nil {
		return nil
	}
	client, err := alioss.New(cfg.Endpoint, cfg.AccessKeyID, cfg.AccessKeySecret)
	if err != nil {
		return err
	}
	bucket, err := client.Bucket(cfg.Bucket)
	if err != nil {
		return err
	}
	return bucket.DeleteObject(objectKey)
}

// ParseObjectKeyFromURL 从 OSS 公网 URL 解析出 objectKey
// 格式: https://bucket.oss-cn-xxx.aliyuncs.com/uploads/avatars/xxx.jpg
func ParseObjectKeyFromURL(rawURL string) string {
	u, err := url.Parse(rawURL)
	if err != nil {
		return ""
	}
	path := strings.TrimPrefix(u.Path, "/")
	return path
}

// IsOSSURL 判断是否为 OSS 公网 URL（用于删除时区分本地/OSS）
func IsOSSURL(rawURL string) bool {
	cfg := LoadConfig()
	if cfg == nil {
		return false
	}
	// 格式: https://{bucket}.{endpoint}/...
	prefix := "https://" + cfg.Bucket + "." + cfg.Endpoint + "/"
	return strings.HasPrefix(rawURL, prefix)
}