package conversion

import (
	"fmt"

	"github.com/subconverter-go/internal/config"
	"github.com/subconverter-go/internal/logging"
)

// Converter 代理订阅转换器
// 负责在不同代理格式之间进行转换
type Converter struct {
	logger    *logging.Logger
	configMgr *config.ConfigManager
}

// NewConverter 创建新的转换器
// 返回初始化好的Converter实例
func NewConverter(logger *logging.Logger, configMgr *config.ConfigManager) *Converter {
	return &Converter{
		logger:    logger,
		configMgr: configMgr,
	}
}

// Convert 执行转换操作
// 将输入的订阅转换为指定格式的配置
func (c *Converter) Convert(req *ConversionRequest) (*ConversionResponse, error) {
	c.logger.Infof("Converting subscription from %s to %s format", req.SourceSummary(), req.Target)

	// 这里实现实际的转换逻辑
	// 目前只是占位符，后续会实现完整的转换功能

	// 验证目标格式是否支持
	if !c.isTargetSupported(req.Target) {
		return nil, fmt.Errorf("unsupported target format: %s", req.Target)
	}

	// 创建响应
	resp := NewConversionResponse()
	resp.Success = true
	resp.Content = "# Placeholder converted configuration\n# Target: " + req.Target + "\n# Source: " + req.SourceSummary() + "\n"
	resp.ContentType = "text/plain"
	resp.TargetFormat = req.Target
	resp.SourceURL = req.SourceSummary()
	resp.ConfigURL = req.ConfigURL
	resp.NodeCount = 0
	resp.ProcessingTime = 0

	c.logger.Infof("Conversion completed successfully for target: %s", req.Target)
	return resp, nil
}

// isTargetSupported 检查目标格式是否支持
func (c *Converter) isTargetSupported(target string) bool {
	config := c.configMgr.GetConfig()
	supportedTargets := config.Conversion.SupportedTargets

	for _, supported := range supportedTargets {
		if supported == target {
			return true
		}
	}

	return false
}

// GetSupportedTargets 获取支持的目标格式列表
func (c *Converter) GetSupportedTargets() []string {
	config := c.configMgr.GetConfig()
	return config.Conversion.SupportedTargets
}

// ValidateRequest 验证转换请求
func (c *Converter) ValidateRequest(req *ConversionRequest) error {
	// 验证目标格式
	if !c.isTargetSupported(req.Target) {
		return fmt.Errorf("unsupported target format: %s", req.Target)
	}

	// 验证订阅URL
	if len(req.GetSources()) == 0 {
		return fmt.Errorf("subscription URL is required")
	}

	// 验证配置URL（如果提供）
	if req.ConfigURL != "" {
		// 这里应该验证URL格式
		// 目前简单检查不为空
	}

	return nil
}

// GetStatistics 获取转换统计信息
func (c *Converter) GetStatistics() map[string]interface{} {
	// 返回转换统计信息
	return map[string]interface{}{
		"total_conversions":      0,
		"successful_conversions": 0,
		"failed_conversions":     0,
		"cache_hits":             0,
		"cache_misses":           0,
		"supported_targets":      c.GetSupportedTargets(),
	}
}