package oauth2

import (
	"context"
	"errors"
	"fmt"
	"io"
	"net"
	"net/http"
	"net/http/cookiejar"
	"net/http/httptest"
	"net/url"
	"regexp"
	"strings"
	"testing"

	"gitea.inhome.blapointe.com/local/oauth2"
	"gitea.inhome.blapointe.com/local/oauth2/oauth2client"
	"gitea.inhome.blapointe.com/local/oauth2/oauth2server/config"
	"gitea.inhome.blapointe.com/local/oauth2/oauth2server/server"
)

func TestAll(t *testing.T) {
	oauth2client.HTTPClient.Transport = makeTransport()

	oauth2server, err := launchServer()
	if err != nil {
		t.Fatal(err)
	}
	defer oauth2server.Close()
	oauth2server.URL = strings.ReplaceAll(oauth2server.URL, "127.0.0.1", "echo.belbox.dev")

	s := dummyServer(t, oauth2server.URL)
	defer s.Close()

	t.Log("createUser...")
	if err := createUser(oauth2server.URL); err != nil {
		t.Fatal(err)
	}

	t.Log("loginAsUser...")
	if err := loginAsuser(oauth2server.URL); err != nil {
		t.Fatal(err)
	}

	t.Log("shouldRedir...")
	if err := shouldRedir(s.URL); err != nil {
		t.Fatal(err)
	}

	t.Log("testAuth...")
	if err := testAuth(oauth2server.URL, s.URL); err != nil {
		t.Fatal(err)
	}

	t.Log("testAuthViaBadBasicAuth...")
	if err := testAuthViaBadBasicAuth(s.URL); err != nil {
		t.Fatal(err)
	}

	t.Log("testAuthViaBasicAuth...")
	if err := testAuthViaBasicAuth(s.URL); err != nil {
		t.Fatal(err)
	}
}

func launchServer() (*httptest.Server, error) {
	config.Store = "map"
	config.UserRegistration = true

	oauth2server := server.New()
	err := oauth2server.Routes()
	if err != nil {
		return nil, err
	}
	s := httptest.NewServer(oauth2server)

	re := regexp.MustCompile(":[0-9]*")
	port := re.FindString(s.URL)
	config.Port = port

	return s, err
}

func dummyServer(t *testing.T, oauth2server string) *httptest.Server {
	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		err := oauth2client.Authenticate(oauth2server, "scope", w, r)
		if err != nil {
			t.Logf("dummy: %s: %v", r.URL.Path, err)
			return
		}
		t.Logf("dummy: %s: :D", r.URL.Path)
		fmt.Fprintln(w, "dummy server serving authenticated")
	}))
}

func createUser(oauth2server string) error {
	req, _ := http.NewRequest(http.MethodPost, oauth2server+"/users/submit/scope", strings.NewReader("username=abc"))
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	resp, err := makeClient().Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		return errors.New("bad status " + resp.Status)
	}
	return nil
}

func loginAsuser(oauth2server string) error {
	req, _ := http.NewRequest(http.MethodPost, oauth2server+"/authorize/scope", strings.NewReader("username=abc"))
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	resp, err := makeClient().Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		return errors.New("bad status " + resp.Status)
	}
	return nil
}

func shouldRedir(dummy string) error {
	c := makeClient()
	return clientShouldRedir(c, dummy)
}

func clientShouldRedir(c *http.Client, dummy string) error {
	req, _ := http.NewRequest("GET", dummy, nil)
	resp, err := c.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != 403 || resp.Header.Get("WWW-Authenticate") == "" {
		return fmt.Errorf("did not need redir without auth: (%d) %q", resp.StatusCode, resp.Header.Get("WWW-Authenticate"))
	}
	return nil
}

func clientShouldNotRedir(c *http.Client, dummy string) error {
	req, _ := http.NewRequest("GET", dummy, nil)
	resp, err := c.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.Request.URL.Path == "/users/log/scope" {
		return fmt.Errorf("did redir with auth: %v", resp.Request.URL.Path)
	}
	return nil
}

func testAuth(oauth2server, dummy string) error {
	c := makeClient()
	if err := clientShouldRedir(c, dummy); err != nil {
		return err
	}
	access, err := clientLogin(c, oauth2server)
	if err != nil {
		return err
	}
	if err := clientShouldNotRedir(c, dummy+"?"+oauth2.NEWCOOKIE+"="+access); err != nil {
		return err
	}
	if !strings.Contains(fmt.Sprint(c.Jar), oauth2.COOKIE) {
		return errors.New("cookie jar empty:" + fmt.Sprint(c.Jar))
	}
	return nil
}

func clientLogin(c *http.Client, oauth2server string) (string, error) {
	req, _ := http.NewRequest("POST", oauth2server+"/authorize/scope?"+oauth2.REDIRECT+"="+oauth2server+"/", strings.NewReader("username=abc"))
	req.Header.Add("Content-Type", "application/x-www-form-urlencoded")
	resp, err := c.Do(req)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()
	if resp.StatusCode == http.StatusUnauthorized {
		return "", fmt.Errorf("bad status; %v", resp.StatusCode)
	}
	if resp.Request.URL.Path != "/" {
		return "", fmt.Errorf("login response path wrong: %v", resp.Request.URL.Path)
	}
	a := resp.Request.URL.Query().Get(oauth2.NEWCOOKIE)
	if a == "" {
		cookies := c.Jar.Cookies(&url.URL{Scheme: "http", Path: "/", Host: "echo.belbox.dev"})
		for i := range cookies {
			if cookies[i].Name == oauth2.NEWCOOKIE {
				a = cookies[i].Value
			}
		}
	}
	if a == "" {
		return "", fmt.Errorf("login and redir didnt set cookie: %v", a)
	}
	return a, nil
}

func testAuthViaBadBasicAuth(dummy string) error {
	c := makeClient()
	req, _ := http.NewRequest(http.MethodGet, dummy, nil)
	req.SetBasicAuth("u", "p")
	resp, err := c.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != 403 {
		b, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("got through with bad basic auth set: (%d) %s", resp.StatusCode, b)
	}
	return nil
}

func testAuthViaBasicAuth(dummy string) error {
	c := makeClient()
	req, _ := http.NewRequest(http.MethodGet, dummy, nil)
	req.SetBasicAuth("", "abc")
	resp, err := c.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		b, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("failed to get through with basic auth set: (%d) %s", resp.StatusCode, b)
	}
	if !strings.Contains(fmt.Sprint(c.Jar), oauth2.COOKIE) {
		return errors.New("cookie jar empty:" + fmt.Sprint(c.Jar))
	}
	return nil
}

func makeClient() *http.Client {
	jar, _ := cookiejar.New(&cookiejar.Options{})
	return &http.Client{
		Jar:       jar,
		Transport: makeTransport(),
	}
}

func makeTransport() *http.Transport {
	return &http.Transport{
		DialContext: func(ctx context.Context, network string, addr string) (net.Conn, error) {
			parts := strings.Split(addr, ":")
			port := "80"
			if len(parts) > 0 {
				port = parts[1]
			}
			return (&net.Dialer{}).DialContext(ctx, "tcp4", fmt.Sprintf("127.0.0.1:%s", port))
		},
	}
}