package tokens

import (
	"encoding/json"
	"fmt"
	"io/ioutil"
	"net/http"
	"time"

	"github.com/rancher/norman/httperror"
	"github.com/rancher/norman/types"
	"github.com/rancher/rancher/pkg/auth/util"
	"github.com/rancher/types/apis/management.cattle.io/v3"
	"github.com/sirupsen/logrus"
)

const (
	CookieName      = "R_SESS"
	AuthHeaderName  = "Authorization"
	AuthValuePrefix = "Bearer"
	BasicAuthPrefix = "Basic"
)

func tokenActionHandler(actionName string, action *types.Action, request *types.APIContext) error {
	logrus.Debugf("TokenActionHandler called for action %v", actionName)
	if actionName == "logout" {
		return tokenServer.logout(actionName, action, request)
	}
	return httperror.NewAPIError(httperror.ActionNotAvailable, "")
}

func tokenCreateHandler(request *types.APIContext, _ types.RequestHandler) error {
	logrus.Debugf("TokenCreateHandler called")
	return tokenServer.deriveToken(request)
}

func tokenListHandler(request *types.APIContext, _ types.RequestHandler) error {
	logrus.Debugf("TokenListHandler called")
	if request.ID != "" {
		return tokenServer.getToken(request)
	}
	return tokenServer.listTokens(request)
}

func tokenDeleteHandler(request *types.APIContext, _ types.RequestHandler) error {
	logrus.Debugf("TokenDeleteHandler called")
	return tokenServer.removeToken(request)
}

func (s *tokenAPIServer) deriveToken(request *types.APIContext) error {

	r := request.Request

	tokenAuthValue := GetTokenAuthFromRequest(r)
	if tokenAuthValue == "" {
		// no cookie or auth header, cannot authenticate
		return httperror.NewAPIErrorLong(http.StatusUnauthorized, util.GetHTTPErrorCode(http.StatusUnauthorized), "No valid token cookie or auth header")
	}

	bytes, err := ioutil.ReadAll(r.Body)
	if err != nil {
		logrus.Errorf("GetToken failed with error: %v", err)
	}
	jsonInput := v3.Token{}

	err = json.Unmarshal(bytes, &jsonInput)
	if err != nil {
		logrus.Errorf("unmarshal failed with error: %v", err)
	}

	var token v3.Token
	var status int

	// create derived token
	token, status, err = s.createDerivedToken(jsonInput, tokenAuthValue)
	if err != nil {
		logrus.Errorf("deriveToken failed with error: %v", err)
		if status == 0 {
			status = http.StatusInternalServerError
		}
		return httperror.NewAPIErrorLong(status, util.GetHTTPErrorCode(status), fmt.Sprintf("%v", err))
	}

	tokenData, err := ConvertTokenResource(request.Schema, token)
	if err != nil {
		return err
	}
	tokenData["token"] = token.ObjectMeta.Name + ":" + token.Token

	request.WriteResponse(http.StatusCreated, tokenData)

	return nil
}

func (s *tokenAPIServer) listTokens(request *types.APIContext) error {
	r := request.Request

	// TODO switch to X-API-UserId header
	tokenAuthValue := GetTokenAuthFromRequest(r)
	if tokenAuthValue == "" {
		// no cookie or auth header, cannot authenticate
		return httperror.NewAPIErrorLong(http.StatusUnauthorized, util.GetHTTPErrorCode(http.StatusUnauthorized), "No valid token cookie or auth header")
	}
	//getToken
	tokens, status, err := s.getTokens(tokenAuthValue)
	if err != nil {
		logrus.Errorf("GetToken failed with error: %v", err)
		if status == 0 {
			status = http.StatusInternalServerError
		}
		return httperror.NewAPIErrorLong(status, util.GetHTTPErrorCode(status), fmt.Sprintf("%v", err))
	}

	tokensFromStore := make([]map[string]interface{}, len(tokens))
	for _, token := range tokens {
		tokenData, err := ConvertTokenResource(request.Schema, token)
		if err != nil {
			return err
		}

		tokensFromStore = append(tokensFromStore, tokenData)
	}

	request.WriteResponse(http.StatusOK, tokensFromStore)
	return nil
}

func (s *tokenAPIServer) logout(actionName string, action *types.Action, request *types.APIContext) error {
	r := request.Request
	w := request.Response

	tokenAuthValue := GetTokenAuthFromRequest(r)
	if tokenAuthValue == "" {
		// no cookie or auth header, cannot authenticate
		return httperror.NewAPIErrorLong(http.StatusUnauthorized, util.GetHTTPErrorCode(http.StatusUnauthorized), "No valid token cookie or auth header")
	}

	isSecure := false
	if r.URL.Scheme == "https" {
		isSecure = true
	}

	tokenCookie := &http.Cookie{
		Name:     CookieName,
		Value:    "",
		Secure:   isSecure,
		Path:     "/",
		HttpOnly: true,
		MaxAge:   -1,
		Expires:  time.Date(1982, time.February, 10, 23, 0, 0, 0, time.UTC),
	}
	http.SetCookie(w, tokenCookie)

	//getToken
	status, err := s.deleteToken(tokenAuthValue)
	if err != nil {
		logrus.Errorf("DeleteToken failed with error: %v", err)
		if status == 0 {
			status = http.StatusInternalServerError
		}
		return httperror.NewAPIErrorLong(status, util.GetHTTPErrorCode(status), fmt.Sprintf("%v", err))
	}
	return nil
}

func (s *tokenAPIServer) getToken(request *types.APIContext) error {
	// TODO switch to X-API-UserId header
	r := request.Request

	tokenAuthValue := GetTokenAuthFromRequest(r)
	if tokenAuthValue == "" {
		// no cookie or auth header, cannot authenticate
		return httperror.NewAPIErrorLong(http.StatusUnauthorized, util.GetHTTPErrorCode(http.StatusUnauthorized), "No valid token cookie or auth header")
	}

	tokenID := request.ID

	//getToken
	token, status, err := s.getTokenByID(tokenAuthValue, tokenID)
	if err != nil {
		logrus.Errorf("GetToken failed with error: %v", err)
		if status == 0 {
			status = http.StatusInternalServerError
		} else if status == 410 {
			status = http.StatusNotFound
		}
		return httperror.NewAPIErrorLong(status, util.GetHTTPErrorCode(status), fmt.Sprintf("%v", err))
	}
	tokenData, err := ConvertTokenResource(request.Schema, token)
	if err != nil {
		return err
	}
	request.WriteResponse(http.StatusOK, tokenData)
	return nil
}

func (s *tokenAPIServer) removeToken(request *types.APIContext) error {
	// TODO switch to X-API-UserId header
	r := request.Request

	tokenAuthValue := GetTokenAuthFromRequest(r)
	if tokenAuthValue == "" {
		// no cookie or auth header, cannot authenticate
		return httperror.NewAPIErrorLong(http.StatusUnauthorized, util.GetHTTPErrorCode(http.StatusUnauthorized), "No valid token cookie or auth header")
	}
	tokenID := request.ID

	//getToken
	t, status, err := s.getTokenByID(tokenAuthValue, tokenID)
	if err != nil {
		if status != 410 {
			logrus.Errorf("DeleteToken Failed to fetch the token to delete with error: %v", err)
			if status == 0 {
				status = http.StatusInternalServerError
			}
			return httperror.NewAPIErrorLong(status, util.GetHTTPErrorCode(status), fmt.Sprintf("%v", err))
		}
	}

	currentAuthToken, _, err := s.getK8sTokenCR(tokenAuthValue)
	if err != nil {
		return err
	}

	if currentAuthToken.Name == t.Name && !currentAuthToken.IsDerived {
		return httperror.NewAPIErrorLong(http.StatusBadRequest, util.GetHTTPErrorCode(http.StatusBadRequest), "Cannot delete token for current session. Use logout instead")
	}

	if _, err := tokenServer.deleteTokenByName(t.Name); err != nil {
		return err
	}

	request.WriteResponse(http.StatusNoContent, nil)
	return nil
}