/**
 *   OpenPlenary - Open your city council plenaries
 *   Copyright (C) 2013  Indignats de Cardedeu (indignatsdecardedeu@gmail.com)
 *
 *   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/>.
 */

import grails.converters.JSON

import javax.servlet.http.HttpServletResponse

import org.codehaus.groovy.grails.plugins.springsecurity.SpringSecurityUtils

import org.springframework.security.authentication.AccountExpiredException
import org.springframework.security.authentication.CredentialsExpiredException
import org.springframework.security.authentication.DisabledException
import org.springframework.security.authentication.LockedException
import org.springframework.security.core.context.SecurityContextHolder as SCH
import org.springframework.security.web.WebAttributes
import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter

class LoginController {

	/**
	 * Dependency injection for the authenticationTrustResolver.
	 */
	def authenticationTrustResolver

	/**
	 * Dependency injection for the springSecurityService.
	 */
	def springSecurityService

	/**
	 * Default action; redirects to 'defaultTargetUrl' if logged in, /login/auth otherwise.
	 */
	def index = {
		if (springSecurityService.isLoggedIn()) {
			redirect uri: SpringSecurityUtils.securityConfig.successHandler.defaultTargetUrl
		}
		else {
			redirect action: 'auth', params: params
		}
	}

	/**
	 * Show the login page.
	 */
	def auth = {

		def config = SpringSecurityUtils.securityConfig

		if (springSecurityService.isLoggedIn()) {
			redirect uri: config.successHandler.defaultTargetUrl
			return
		}

		String view = '../webUser/signup'
		String postUrl = "${request.contextPath}${config.apf.filterProcessesUrl}"
		render( view: view, model: [postUrl: postUrl,
		                           rememberMeParameter: config.rememberMe.parameter])
	}

	/**
	 * The redirect action for Ajax requests.
	 */
	def authAjax = {
		response.setHeader 'Location', SpringSecurityUtils.securityConfig.auth.ajaxLoginFormUrl
		response.sendError HttpServletResponse.SC_UNAUTHORIZED
	}

	/**
	 * Show denied page.
	 */
	def denied = {
		if (springSecurityService.isLoggedIn() &&
				authenticationTrustResolver.isRememberMe(SCH.context?.authentication)) {
			// have cookie but the page is guarded with IS_AUTHENTICATED_FULLY
			redirect action: 'full', params: params
		}
	}

	/**
	 * Login page for users with a remember-me cookie but accessing a IS_AUTHENTICATED_FULLY page.
	 */
	def full = {
		def config = SpringSecurityUtils.securityConfig
		render view: 'auth', params: params,
			model: [hasCookie: authenticationTrustResolver.isRememberMe(SCH.context?.authentication),
			        postUrl: "${request.contextPath}${config.apf.filterProcessesUrl}"]
	}

	/**
	 * Callback after a failed login. Redirects to the auth page with a warning message.
	 */
	def authfail = {

		def username = session[UsernamePasswordAuthenticationFilter.SPRING_SECURITY_LAST_USERNAME_KEY]
		String msg = ''
		def exception = session[WebAttributes.AUTHENTICATION_EXCEPTION]
		if (exception) {
			if (exception instanceof AccountExpiredException) {
				msg = g.message(code: "springSecurity.errors.login.expired")
			}
			else if (exception instanceof CredentialsExpiredException) {
				msg = g.message(code: "springSecurity.errors.login.passwordExpired")
			}
			else if (exception instanceof DisabledException) {
				msg = g.message(code: "springSecurity.errors.login.disabled")
			}
			else if (exception instanceof LockedException) {
				msg = g.message(code: "springSecurity.errors.login.locked")
			}
			else {
				msg = g.message(code: "springSecurity.errors.login.fail")
			}
		}

		if (springSecurityService.isAjax(request)) {
			render([error: msg] as JSON)
		}
		else {
			flash.message = msg
			redirect action: 'auth', params: params
		}
	}

	/**
	 * The Ajax success redirect url.
	 */
	def ajaxSuccess = {
		render([success: true, username: springSecurityService.authentication.name] as JSON)
	}

	/**
	 * The Ajax denied redirect url.
	 */
	def ajaxDenied = {
		render([error: 'access denied'] as JSON)
	}
}
