package test

import (
	"crypto/tls"
	"encoding/json"
	"fmt"
	"io"
	"net"
	"net/http"
	"os"
	"testing"
	"time"

	"github.com/go-chi/chi/v5"
	"github.com/go-chi/render"
	. "github.com/smartystreets/goconvey/convey"
	"scm.yoorie.de/go-lib/micro/web"
	"scm.yoorie.de/go-lib/util"
)

var (
	internalCount int
	httpPort      int
	sslPort       int
)

const (
	readyMessage   = "service is ready"
	aMessage       = "A message"
	testFailureMsg = "test failure"
)

type MyData struct {
	Message string `json:"message"`
	Count   int    `json:"count"`
}

func MyTestEndpoint(w http.ResponseWriter, r *http.Request) {
	internalCount++
	render.JSON(w, r, &MyData{
		Message: aMessage,
		Count:   internalCount,
	})
}

func CreateTestRouter() *chi.Mux {
	router := chi.NewRouter()
	router.Get("/myendpoint", MyTestEndpoint)
	return router
}

// GetFreePort asks the kernel for a free open port that is ready to use.
func GetFreePort() (int, error) {
	addr, err := net.ResolveTCPAddr("tcp", "localhost:0")
	if err != nil {
		return 0, err
	}

	l, err := net.ListenTCP("tcp", addr)
	if err != nil {
		return 0, err
	}
	defer l.Close()
	return l.Addr().(*net.TCPAddr).Port, nil
}

func getServerURL(ssl bool, path string) string {
	var scheme string
	var port int
	if ssl {
		scheme = "https"
		port = sslPort
	} else {
		scheme = "http"
		port = httpPort
	}
	return util.JoiningSlash(fmt.Sprintf("%s://localhost:%d", scheme, port), path)
}

func TestMain(m *testing.M) {
	internalCount = 0
	var err error
	httpPort, err = GetFreePort()
	if err != nil {
		panic(err)
	}
	sslPort, err = GetFreePort()
	if err != nil {
		panic(err)
	}
	config := &web.WebServerConfiguration{
		Port:    httpPort,
		SslPort: sslPort,
	}
	server, err := web.NewWebServer(config)
	if err != nil {
		panic(err)
	}
	server.Mount("/api", CreateTestRouter())
	if err = server.Start(); err != nil {
		panic(err)
	}

	// Allow insecure calls to https
	http.DefaultTransport.(*http.Transport).TLSClientConfig = &tls.Config{InsecureSkipVerify: true}

	exitVal := m.Run()
	server.Stop()
	os.Exit(exitVal)
}

func TestNewWebServerNilConfig(t *testing.T) {
	Convey("NewWebServer with nil config returns error", t, func() {
		server, err := web.NewWebServer(nil)
		So(err, ShouldNotBeNil)
		So(server, ShouldBeNil)
	})
}

func TestGetBindings(t *testing.T) {
	Convey("WebServerConfiguration.GetBindings", t, func() {
		Convey("returns only http binding when SSL port is 0", func() {
			config := &web.WebServerConfiguration{Port: 8080}
			So(config.GetBindings(), ShouldEqual, "http://0.0.0.0:8080")
		})
		Convey("returns https and http bindings when SSL port is set", func() {
			config := &web.WebServerConfiguration{Port: 8080, SslPort: 8443}
			So(config.GetBindings(), ShouldEqual, "https://0.0.0.0:8443,http://0.0.0.0:8080")
		})
	})
}

func TestBuildHostAddress(t *testing.T) {
	Convey("WebServerConfiguration.BuildHostAddress", t, func() {
		Convey("uses 0.0.0.0 when host is empty", func() {
			config := &web.WebServerConfiguration{Port: 8080, SslPort: 8443}
			So(config.BuildHostAddress(false), ShouldEqual, "0.0.0.0:8080")
			So(config.BuildHostAddress(true), ShouldEqual, "0.0.0.0:8443")
		})
		Convey("uses configured host when set", func() {
			config := &web.WebServerConfiguration{Host: "192.168.1.1", Port: 8080, SslPort: 8443}
			So(config.BuildHostAddress(false), ShouldEqual, "192.168.1.1:8080")
			So(config.BuildHostAddress(true), ShouldEqual, "192.168.1.1:8443")
		})
	})
}

func TestStartWithNoMounts(t *testing.T) {
	Convey("Start returns error when no mounts are registered", t, func() {
		port, err := GetFreePort()
		So(err, ShouldBeNil)

		config := &web.WebServerConfiguration{Port: port}
		server, err := web.NewWebServer(config)
		So(err, ShouldBeNil)

		err = server.Start()
		So(err, ShouldNotBeNil)
	})
}

func TestNonSSLServer(t *testing.T) {
	Convey("Non-SSL web server starts, serves requests, and stops", t, func() {
		port, err := GetFreePort()
		So(err, ShouldBeNil)

		config := &web.WebServerConfiguration{Port: port}
		server, err := web.NewWebServer(config)
		So(err, ShouldBeNil)

		server.Mount("/api", CreateTestRouter())
		err = server.Start()
		So(err, ShouldBeNil)

		time.Sleep(100 * time.Millisecond)

		uri := fmt.Sprintf("http://localhost:%d/health/readyz", port)
		resp, err := http.Get(uri)
		So(err, ShouldBeNil)
		So(resp.StatusCode, ShouldEqual, http.StatusOK)

		body, _ := io.ReadAll(resp.Body)
		healthData := web.HealthData{}
		err = json.Unmarshal(body, &healthData)
		So(err, ShouldBeNil)
		So(healthData.Message, ShouldEqual, readyMessage)

		server.Stop()
	})
}

func TestUnhealthyServer(t *testing.T) {
	Convey("Server with failing HealthCheck returns 503 from healthz endpoint", t, func() {
		port, err := GetFreePort()
		So(err, ShouldBeNil)

		config := &web.WebServerConfiguration{Port: port}
		server, err := web.NewWebServer(config)
		So(err, ShouldBeNil)

		server.HealthCheck = func() (bool, string) { return false, testFailureMsg }
		server.Mount("/api", CreateTestRouter())
		err = server.Start()
		So(err, ShouldBeNil)

		time.Sleep(100 * time.Millisecond)

		uri := fmt.Sprintf("http://localhost:%d/health/healthz", port)
		resp, err := http.Get(uri)
		So(err, ShouldBeNil)
		So(resp.StatusCode, ShouldEqual, http.StatusServiceUnavailable)

		server.Stop()
	})
}

func TestReady(t *testing.T) {
	Convey("HTTP ready endpoint returns 200 with ready message", t, func() {
		uri := getServerURL(false, "/readyz")
		resp, err := http.Get(uri)
		So(err, ShouldBeNil)
		So(resp.StatusCode, ShouldEqual, http.StatusOK)
		body, _ := io.ReadAll(resp.Body)
		healthData := web.HealthData{}
		err = json.Unmarshal(body, &healthData)
		So(err, ShouldBeNil)
		So(healthData.Message, ShouldEqual, readyMessage)
		So(healthData.LastChecked, ShouldNotBeZeroValue)
	})
}

func TestReadySSL(t *testing.T) {
	Convey("HTTPS ready endpoint returns 200 with ready message", t, func() {
		uri := getServerURL(true, "/health/readyz")
		resp, err := http.Get(uri)
		So(err, ShouldBeNil)
		So(resp.StatusCode, ShouldEqual, http.StatusOK)
		body, _ := io.ReadAll(resp.Body)
		healthData := web.HealthData{}
		err = json.Unmarshal(body, &healthData)
		So(err, ShouldBeNil)
		So(healthData.Message, ShouldEqual, readyMessage)
		So(healthData.LastChecked, ShouldNotBeZeroValue)
	})
}

func TestHealthy(t *testing.T) {
	Convey("Healthy endpoint returns 200 with running message", t, func() {
		resp, err := http.Get(getServerURL(false, "/healthz"))
		So(err, ShouldBeNil)
		So(resp.StatusCode, ShouldEqual, http.StatusOK)
		body, _ := io.ReadAll(resp.Body)
		healthData := web.HealthData{}
		err = json.Unmarshal(body, &healthData)
		So(err, ShouldBeNil)
		So(healthData.Message, ShouldEqual, "service up and running")
		So(healthData.LastChecked, ShouldNotBeZeroValue)
	})
}

func TestSslEndpoint(t *testing.T) {
	Convey("SSL endpoint returns 200 with expected data", t, func() {
		uri := getServerURL(true, "/api/myendpoint")
		resp, err := http.Get(uri)
		So(err, ShouldBeNil)
		So(resp.StatusCode, ShouldEqual, http.StatusOK)
		body, err := io.ReadAll(resp.Body)
		So(err, ShouldBeNil)
		myData := MyData{}
		err = json.Unmarshal(body, &myData)
		So(err, ShouldBeNil)
		So(myData.Message, ShouldEqual, aMessage)
		So(myData.Count, ShouldBeGreaterThan, 0)
	})
}