// staletea
// Copyright (C) 2019 Jonas Franz
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.

package web

import (
	"code.gitea.io/sdk/gitea"
	"context"
	"gitea.com/jonasfranz/staletea/auth"
	"gitea.com/jonasfranz/staletea/config"
	"gitea.com/jonasfranz/staletea/models"
	"gitea.com/jonasfranz/staletea/utils"
	"github.com/gin-contrib/sessions"
	"github.com/gin-gonic/gin"
	"net/http"
)

func handleLogin(ctx *gin.Context) {
	session := sessions.Default(ctx)
	state, err := utils.NewSecret(32)
	if err != nil {
		_ = ctx.AbortWithError(500, err)
		return
	}
	session.Set("state", state)
	if err := session.Save(); err != nil {
		_ = ctx.AbortWithError(http.StatusInternalServerError, err)
		return
	}
	redirectURL := auth.Config().AuthCodeURL(state)
	ctx.Redirect(http.StatusTemporaryRedirect, redirectURL)
}

func handleCallback(ctx *gin.Context) {
	session := sessions.Default(ctx)
	state := ctx.Query("state")
	savedState := session.Get("state")
	if savedState == nil {
		ctx.String(http.StatusUnauthorized, "Invalid state")
		return
	}
	session.Delete("state")
	if parsedState, ok := savedState.(string); !ok || parsedState != state {
		ctx.String(http.StatusUnauthorized, "Invalid state")
		return
	}
	token, err := auth.Config().Exchange(ctx, ctx.Query("code"))
	if err != nil {
		_ = ctx.AbortWithError(http.StatusUnauthorized, err)
		return
	}
	client := gitea.NewClient(config.GiteaURL.Get().(string), "")
	client.SetHTTPClient(auth.Config().Client(context.Background(), token))
	user, err := client.GetMyUserInfo()
	if err != nil {
		_ = ctx.AbortWithError(http.StatusUnauthorized, err)
		return
	}
	storedUser := &models.User{
		ID:       user.ID,
		Username: user.UserName,
		Token:    token,
	}
	if err := models.InsertOrUpdateUser(storedUser); err != nil {
		_ = ctx.AbortWithError(http.StatusInternalServerError, err)
		return
	}
	session.Set("user", storedUser)
	if err := session.Save(); err != nil {
		_ = ctx.AbortWithError(http.StatusInternalServerError, err)
		return
	}
	ctx.Redirect(http.StatusTemporaryRedirect, config.BaseURL.Get().(string))
}