package handler

import (
	"net/http"
	"time"

	"github.com/gin-gonic/gin"

	"nex/backend/internal/service"
)

// StatsHandler 统计处理器
type StatsHandler struct {
	statsService service.StatsService
}

// NewStatsHandler 创建统计处理器
func NewStatsHandler(statsService service.StatsService) *StatsHandler {
	return &StatsHandler{statsService: statsService}
}

// GetStats 查询统计
func (h *StatsHandler) GetStats(c *gin.Context) {
	providerID := c.Query("provider_id")
	modelName := c.Query("model_name")
	startDateStr := c.Query("start_date")
	endDateStr := c.Query("end_date")

	var startDate, endDate *time.Time

	if startDateStr != "" {
		t, err := time.Parse("2006-01-02", startDateStr)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{
				"error": "无效的 start_date 格式，应为 YYYY-MM-DD",
			})
			return
		}
		startDate = &t
	}

	if endDateStr != "" {
		t, err := time.Parse("2006-01-02", endDateStr)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{
				"error": "无效的 end_date 格式，应为 YYYY-MM-DD",
			})
			return
		}
		endDate = &t
	}

	stats, err := h.statsService.Get(providerID, modelName, startDate, endDate)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{
			"error": "查询统计失败: " + err.Error(),
		})
		return
	}

	c.JSON(http.StatusOK, stats)
}

// AggregateStats 聚合统计
func (h *StatsHandler) AggregateStats(c *gin.Context) {
	providerID := c.Query("provider_id")
	modelName := c.Query("model_name")
	startDateStr := c.Query("start_date")
	endDateStr := c.Query("end_date")
	groupBy := c.Query("group_by")

	var startDate, endDate *time.Time

	if startDateStr != "" {
		t, err := time.Parse("2006-01-02", startDateStr)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{
				"error": "无效的 start_date 格式，应为 YYYY-MM-DD",
			})
			return
		}
		startDate = &t
	}

	if endDateStr != "" {
		t, err := time.Parse("2006-01-02", endDateStr)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{
				"error": "无效的 end_date 格式，应为 YYYY-MM-DD",
			})
			return
		}
		endDate = &t
	}

	stats, err := h.statsService.Get(providerID, modelName, startDate, endDate)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{
			"error": "查询统计失败: " + err.Error(),
		})
		return
	}

	result := h.statsService.Aggregate(stats, groupBy)
	c.JSON(http.StatusOK, result)
}