package httpapi

import (
	"context"
	"log/slog"
	"net/http"
	"time"

	"github.com/google/uuid"
)

type ctxKey string

const requestIDKey ctxKey = "request_id"

func RequestID(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		requestID := r.Header.Get("X-Request-Id")
		if requestID == "" {
			requestID = uuid.NewString()
		}
		w.Header().Set("X-Request-Id", requestID)
		ctx := context.WithValue(r.Context(), requestIDKey, requestID)
		next.ServeHTTP(w, r.WithContext(ctx))
	})
}

func RequestIDFromContext(ctx context.Context) string {
	val := ctx.Value(requestIDKey)
	if val == nil {
		return ""
	}
	id, _ := val.(string)
	return id
}

func Logging(logger *slog.Logger) func(http.Handler) http.Handler {
	return func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			start := time.Now()
			ww := &responseWriter{ResponseWriter: w, status: http.StatusOK}
			next.ServeHTTP(ww, r)
			logger.Info("request",
				"method", r.Method,
				"path", r.URL.Path,
				"status", ww.status,
				"duration_ms", time.Since(start).Milliseconds(),
				"request_id", RequestIDFromContext(r.Context()),
			)
		})
	}
}

type responseWriter struct {
	http.ResponseWriter
	status int
}

func (w *responseWriter) WriteHeader(status int) {
	w.status = status
	w.ResponseWriter.WriteHeader(status)
}