package server_test

import (
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"sneak.berlin/go/netwatch/internal/config"
	"sneak.berlin/go/netwatch/internal/globals"
	"sneak.berlin/go/netwatch/internal/handlers"
	"sneak.berlin/go/netwatch/internal/healthcheck"
	"sneak.berlin/go/netwatch/internal/logger"
	"sneak.berlin/go/netwatch/internal/middleware"
	"sneak.berlin/go/netwatch/internal/reportbuf"
	"sneak.berlin/go/netwatch/internal/server"

	"go.uber.org/fx"
	"go.uber.org/fx/fxtest"
)

// newServer builds the server from the same constructors as main,
// never started: SetupRoutes is called directly, so nothing listens.
func newServer(t *testing.T) *server.Server {
	t.Helper()

	var srv *server.Server

	app := fxtest.New(t,
		fx.Provide(
			config.New,
			globals.New,
			handlers.New,
			healthcheck.New,
			logger.New,
			middleware.New,
			reportbuf.New,
			server.New,
		),
		fx.Populate(&srv),
	)

	err := app.Err()
	if err != nil {
		t.Fatalf("build server: %v", err)
	}

	srv.SetupRoutes()

	return srv
}

// TestReportsAreRateLimited checks that POST /api/v1/reports is
// behind the per-address rate limit, set here to two a minute.
func TestReportsAreRateLimited(t *testing.T) {
	t.Setenv("REPORTS_PER_MINUTE", "2")

	srv := newServer(t)

	post := func() int {
		rec := httptest.NewRecorder()
		req := httptest.NewRequestWithContext(t.Context(),
			http.MethodPost, "/api/v1/reports",
			strings.NewReader(`{"clientId":"c1","hosts":[]}`),
		)
		srv.ServeHTTP(rec, req)

		return rec.Code
	}

	for i := range 2 {
		if code := post(); code != http.StatusOK {
			t.Fatalf("report %d: status = %d, want %d",
				i+1, code, http.StatusOK)
		}
	}

	if code := post(); code != http.StatusTooManyRequests {
		t.Fatalf("third report in a minute: status = %d, want %d",
			code, http.StatusTooManyRequests)
	}
}

// TestHealthCheckRejectsOversizeBody sends the health check, which
// never reads its body, a body one byte over the limit. Only the
// router-wide body limit can reject it.
func TestHealthCheckRejectsOversizeBody(t *testing.T) {
	t.Parallel()

	srv := newServer(t)

	rec := httptest.NewRecorder()
	req := httptest.NewRequestWithContext(t.Context(),
		http.MethodGet, "/.well-known/healthcheck",
		strings.NewReader(
			strings.Repeat("x", int(server.MaxRequestBodyBytes)+1),
		),
	)

	srv.ServeHTTP(rec, req)

	if rec.Code != http.StatusRequestEntityTooLarge {
		t.Fatalf("status = %d, want %d",
			rec.Code, http.StatusRequestEntityTooLarge)
	}

	if got := rec.Body.String(); got != "{\"status\":\"error\"}\n" {
		t.Errorf("body = %q, want %q", got, "{\"status\":\"error\"}\n")
	}

	got := rec.Header().Get("Content-Type")
	if got != "application/json; charset=utf-8" {
		t.Errorf("Content-Type = %q, want a JSON content type", got)
	}
}