package com.ainovel.server.service.impl;

import java.math.BigDecimal;
import java.time.LocalDateTime;

import org.springframework.stereotype.Service;

import com.ainovel.server.service.ai.pricing.TokenUsageTrackingService;

import lombok.extern.slf4j.Slf4j;
import reactor.core.publisher.Mono;

/**
 * Token使用追踪服务实现（简化版本）
 * 注意：这是一个基础实现，主要用于支持公共模型管理功能
 * 实际生产环境中应该与真实的使用统计数据库集成
 */
@Slf4j
@Service
public class TokenUsageTrackingServiceImpl implements TokenUsageTrackingService {

    @Override
    public Mono<TokenUsageRecord> recordUsage(TokenUsageRecord usage) {
        // 简化实现：仅记录日志，不持久化
        log.info("记录Token使用: provider={}, modelId={}, inputTokens={}, outputTokens={}, cost={}", 
                usage.provider(), usage.modelId(), usage.inputTokens(), usage.outputTokens(), usage.totalCost());
        return Mono.just(usage);
    }

    @Override
    public Mono<TokenUsageRecord> recordUsage(String userId, String provider, String modelId, 
                                             int inputTokens, int outputTokens, BigDecimal cost) {
        TokenUsageRecord record = TokenUsageRecord.builder()
                .userId(userId)
                .provider(provider)
                .modelId(modelId)
                .inputTokens(inputTokens)
                .outputTokens(outputTokens)
                .totalCost(cost)
                .build();
        return recordUsage(record);
    }

    @Override
    public Mono<TokenUsageStatistics> getUserUsageStatistics(String userId, 
                                                            LocalDateTime startTime, 
                                                            LocalDateTime endTime) {
        // 简化实现：返回空统计
        return Mono.just(createEmptyStatistics("user", userId, startTime, endTime));
    }

    @Override
    public Mono<TokenUsageStatistics> getProviderUsageStatistics(String provider, 
                                                                LocalDateTime startTime, 
                                                                LocalDateTime endTime) {
        // 简化实现：返回空统计
        return Mono.just(createEmptyStatistics("provider", provider, startTime, endTime));
    }
    
    /**
     * 创建空的使用统计
     */
    private TokenUsageStatistics createEmptyStatistics(String scope, String scopeId, 
                                                      LocalDateTime startTime, LocalDateTime endTime) {
        return new TokenUsageStatistics(
                scope,
                scopeId,
                startTime,
                endTime,
                0L,  // totalRequests
                0L,  // totalInputTokens
                0L,  // totalOutputTokens
                0L,  // totalTokens
                BigDecimal.ZERO,  // totalCost
                BigDecimal.ZERO,  // averageCostPerRequest
                BigDecimal.ZERO,  // averageCostPerToken
                null,  // providerBreakdown
                null   // featureBreakdown
        );
    }
}