package middleware

import (
	"fmt"
	"log"
	"time"

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

// LoggingMiddleware creates a custom logging middleware with detailed request information
func LoggingMiddleware() gin.HandlerFunc {
	return gin.LoggerWithFormatter(func(param gin.LogFormatterParams) string {
		// Custom log format with more details
		return fmt.Sprintf("[%s] %s %s %s %d %s \"%s\" %s \"%s\" %s\n",
			param.TimeStamp.Format("2006-01-02 15:04:05"),
			param.ClientIP,
			param.Method,
			param.Path,
			param.StatusCode,
			param.Latency,
			param.Request.UserAgent(),
			param.ErrorMessage,
			param.Request.Referer(),
			formatBodySize(param.BodySize),
		)
	})
}

// StructuredLoggingMiddleware creates a structured logging middleware for better log parsing
func StructuredLoggingMiddleware() gin.HandlerFunc {
	return func(c *gin.Context) {
		// Start timer
		start := time.Now()
		path := c.Request.URL.Path
		raw := c.Request.URL.RawQuery

		// Process request
		c.Next()

		// Calculate latency
		latency := time.Since(start)

		// Get client IP
		clientIP := c.ClientIP()

		// Get method
		method := c.Request.Method

		// Get status code
		statusCode := c.Writer.Status()

		// Get body size
		bodySize := c.Writer.Size()

		// Build full path with query string
		if raw != "" {
			path = path + "?" + raw
		}

		// Log structured information
		log.Printf("REQUEST: method=%s path=%s status=%d latency=%v client_ip=%s body_size=%d user_agent=\"%s\"",
			method,
			path,
			statusCode,
			latency,
			clientIP,
			bodySize,
			c.Request.UserAgent(),
		)

		// Log errors if any
		if len(c.Errors) > 0 {
			log.Printf("ERRORS: %v", c.Errors.String())
		}
	}
}

// formatBodySize formats body size in human readable format
func formatBodySize(size int) string {
	if size == 0 {
		return "0B"
	}

	const unit = 1024
	if size < unit {
		return fmt.Sprintf("%dB", size)
	}

	div, exp := int64(unit), 0
	for n := size / unit; n >= unit; n /= unit {
		div *= unit
		exp++
	}

	return fmt.Sprintf("%.1f%cB", float64(size)/float64(div), "KMGTPE"[exp])
}