package server_test

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"

	"git.codelab.vc/pkg/httpx/server"
)

func TestRouter_NotFoundHandler(t *testing.T) {
	t.Run("custom 404 handler", func(t *testing.T) {
		notFound := http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
			w.Header().Set("Content-Type", "application/json")
			w.WriteHeader(http.StatusNotFound)
			json.NewEncoder(w).Encode(map[string]string{"error": "not found"})
		})

		r := server.NewRouter(server.WithNotFoundHandler(notFound))
		r.HandleFunc("GET /exists", func(w http.ResponseWriter, _ *http.Request) {
			w.WriteHeader(http.StatusOK)
		})

		// Matched route works normally.
		w := httptest.NewRecorder()
		req := httptest.NewRequest(http.MethodGet, "/exists", nil)
		r.ServeHTTP(w, req)

		if w.Code != http.StatusOK {
			t.Fatalf("matched route: got status %d, want %d", w.Code, http.StatusOK)
		}

		// Unmatched route uses custom handler.
		w = httptest.NewRecorder()
		req = httptest.NewRequest(http.MethodGet, "/nope", nil)
		r.ServeHTTP(w, req)

		if w.Code != http.StatusNotFound {
			t.Fatalf("not found: got status %d, want %d", w.Code, http.StatusNotFound)
		}
		if ct := w.Header().Get("Content-Type"); ct != "application/json" {
			t.Fatalf("Content-Type = %q, want %q", ct, "application/json")
		}

		var body map[string]string
		if err := json.Unmarshal(w.Body.Bytes(), &body); err != nil {
			t.Fatalf("unmarshal: %v", err)
		}
		if body["error"] != "not found" {
			t.Fatalf("error = %q, want %q", body["error"], "not found")
		}
	})

	t.Run("default behavior without custom handler", func(t *testing.T) {
		r := server.NewRouter()
		r.HandleFunc("GET /exists", func(w http.ResponseWriter, _ *http.Request) {
			w.WriteHeader(http.StatusOK)
		})

		w := httptest.NewRecorder()
		req := httptest.NewRequest(http.MethodGet, "/nope", nil)
		r.ServeHTTP(w, req)

		// Default ServeMux returns 404.
		if w.Code != http.StatusNotFound {
			t.Fatalf("got status %d, want %d", w.Code, http.StatusNotFound)
		}
	})
}