package middleware

import (
	"strconv"
	"time"

	"ResendIt/internal/logger"

	"github.com/gin-gonic/gin"
	"github.com/rs/zerolog"
)

// StructuredLogger returns a gin middleware that logs HTTP requests in JSON format
func StructuredLogger() gin.HandlerFunc {
	return func(c *gin.Context) {
		start := time.Now()
		path := c.Request.URL.Path
		query := c.Request.URL.RawQuery
		method := c.Request.Method

		c.Next()

		latency := time.Since(start)
		status := c.Writer.Status()
		clientIP := c.ClientIP()
		userAgent := c.Request.UserAgent()
		requestID := c.GetString("request_id")

		evt := logger.Log.Info().
			Str("type", "http_request").
			Str("method", method).
			Str("path", path).
			Str("query", query).
			Int("status", status).
			Dur("latency_ms", latency).
			Str("client_ip", clientIP).
			Str("user_agent", userAgent).
			Str("request_id", requestID)

		if len(c.Errors) > 0 {
			evt = evt.Str("error", c.Errors.ByType(gin.ErrorTypePrivate).String())
		}

		if userID, exists := c.Get("user_id"); exists {
			evt = evt.Str("user_id", userID.(string))
		}
		if username, exists := c.Get("username"); exists {
			evt = evt.Str("username", username.(string))
		}

		evt.Msg("")
	}
}

// RequestIDMiddleware adds a unique request ID to each request
func RequestIDMiddleware() gin.HandlerFunc {
	return func(c *gin.Context) {
		requestID := c.GetHeader("X-Request-ID")
		if requestID == "" {
			requestID = generateRequestID()
		}
		c.Set("request_id", requestID)
		c.Header("X-Request-ID", requestID)
		c.Next()
	}
}

func generateRequestID() string {
	// Simple request ID generation - could use uuid package for more entropy
	return strconv.FormatInt(time.Now().UnixNano(), 36)
}

// StructuredLog returns a child logger with HTTP context for use in handlers
func StructuredLog(c *gin.Context) zerolog.Logger {
	log := logger.Log.With().
		Str("type", "app_log").
		Str("request_id", c.GetString("request_id"))

	if userID, exists := c.Get("user_id"); exists {
		log = log.Str("user_id", userID.(string))
	}
	if username, exists := c.Get("username"); exists {
		log = log.Str("username", username.(string))
	}

	return log.Logger()
}