class UsersController < ApplicationController
  include SessionMethods
  include UserMethods

  layout "site"

  skip_before_action :verify_authenticity_token, :only => [:auth_success]
  before_action :disable_terms_redirect, :only => [:terms, :save]
  before_action :authorize_web
  before_action :set_locale
  before_action :check_database_readable

  authorize_resource

  before_action :check_database_writable, :only => [:new, :go_public]
  before_action :require_cookies, :only => [:new]
  before_action :lookup_user_by_name, :only => [:set_status, :destroy]
  before_action :allow_thirdparty_images, :only => [:show]

  ##
  # display a list of users matching specified criteria
  def index
    if request.post?
      ids = params[:user].keys.collect(&:to_i)

      User.where(:id => ids).update_all(:status => "confirmed") if params[:confirm]
      User.where(:id => ids).update_all(:status => "deleted") if params[:hide]

      redirect_to url_for(:status => params[:status], :ip => params[:ip], :page => params[:page])
    else
      @params = params.permit(:status, :ip)

      conditions = {}
      conditions[:status] = @params[:status] if @params[:status]
      conditions[:creation_ip] = @params[:ip] if @params[:ip]

      @user_pages, @users = paginate(:users,
                                     :conditions => conditions,
                                     :order => :id,
                                     :per_page => 50)
    end
  end

  def show
    @user = User.find_by(:display_name => params[:display_name])

    if @user &&
       (@user.visible? || current_user&.administrator?)
      @title = @user.display_name
    else
      render_unknown_user params[:display_name]
    end
  end

  def new
    @title = t ".title"
    @referer = if params[:referer]
                 safe_referer(params[:referer])
               else
                 session[:referer]
               end

    append_content_security_policy_directives(
      :form_action => %w[accounts.google.com *.facebook.com login.live.com github.com meta.wikimedia.org]
    )

    if current_user
      # The user is logged in already, so don't show them the signup
      # page, instead send them to the home page
      redirect_to @referer || { :controller => "site", :action => "index" }
    elsif params.key?(:auth_provider) && params.key?(:auth_uid)
      self.current_user = User.new(:email => params[:email],
                                   :email_confirmation => params[:email],
                                   :display_name => params[:nickname],
                                   :auth_provider => params[:auth_provider],
                                   :auth_uid => params[:auth_uid])

      flash.now[:notice] = render_to_string :partial => "auth_association"
    else
      check_signup_allowed

      self.current_user = User.new
    end
  end

  def create
    self.current_user = User.new(user_params)

    if check_signup_allowed(current_user.email)
      session[:referer] = safe_referer(params[:referer]) if params[:referer]

      Rails.logger.info "create: #{session[:referer]}"

      if current_user.auth_provider.present? && current_user.pass_crypt.empty?
        # We are creating an account with external authentication and
        # no password was specified so create a random one
        current_user.pass_crypt = SecureRandom.base64(16)
        current_user.pass_crypt_confirmation = current_user.pass_crypt
      end

      if current_user.invalid?
        # Something is wrong with a new user, so rerender the form
        render :action => "new"
      elsif current_user.auth_provider.present?
        # Verify external authenticator before moving on
        session[:new_user] = current_user
        redirect_to auth_url(current_user.auth_provider, current_user.auth_uid), :status => :temporary_redirect
      else
        # Save the user record
        session[:new_user] = current_user
        redirect_to :action => :terms
      end
    end
  end

  ##
  # destroy a user, marking them as deleted and removing personal data
  def destroy
    @user.soft_destroy!
    redirect_to user_path(:display_name => params[:display_name])
  end

  def terms
    @legale = params[:legale] || OSM.ip_to_country(request.remote_ip) || Settings.default_legale
    @text = OSM.legal_text_for_country(@legale)

    if request.xhr?
      render :partial => "terms"
    else
      @title = t ".title"

      if current_user&.terms_agreed?
        # Already agreed to terms, so just show settings
        redirect_to edit_account_path
      elsif current_user.nil? && session[:new_user].nil?
        redirect_to login_path(:referer => request.fullpath)
      end
    end
  end

  def save
    @title = t "users.new.title"

    if params[:decline] || !(params[:read_tou] && params[:read_ct])
      if current_user
        current_user.terms_seen = true

        flash[:notice] = { :partial => "users/terms_declined_flash" } if current_user.save

        referer = safe_referer(params[:referer]) if params[:referer]

        redirect_to referer || edit_account_path
      elsif params[:decline]
        redirect_to t("users.terms.declined"), :allow_other_host => true
      else
        redirect_to :action => :terms
      end
    elsif current_user
      unless current_user.terms_agreed?
        current_user.consider_pd = params[:user][:consider_pd]
        current_user.tou_agreed = Time.now.utc
        current_user.terms_agreed = Time.now.utc
        current_user.terms_seen = true

        flash[:notice] = t "users.new.terms accepted" if current_user.save
      end

      referer = safe_referer(params[:referer]) if params[:referer]

      redirect_to referer || edit_account_path
    else
      self.current_user = session.delete(:new_user)

      if check_signup_allowed(current_user.email)
        current_user.data_public = true
        current_user.description = "" if current_user.description.nil?
        current_user.creation_ip = request.remote_ip
        current_user.languages = http_accept_language.user_preferred_languages
        current_user.terms_agreed = Time.now.utc
        current_user.tou_agreed = Time.now.utc
        current_user.terms_seen = true

        if current_user.auth_uid.blank?
          current_user.auth_provider = nil
          current_user.auth_uid = nil
        end

        if current_user.save
          SIGNUP_IP_LIMITER&.update(request.remote_ip)
          SIGNUP_EMAIL_LIMITER&.update(canonical_email(current_user.email))

          flash[:matomo_goal] = Settings.matomo["goals"]["signup"] if defined?(Settings.matomo)

          referer = welcome_path

          begin
            uri = URI(session[:referer])
            %r{map=(.*)/(.*)/(.*)}.match(uri.fragment) do |m|
              editor = Rack::Utils.parse_query(uri.query).slice("editor")
              referer = welcome_path({ "zoom" => m[1],
                                       "lat" => m[2],
                                       "lon" => m[3] }.merge(editor))
            end
          rescue StandardError
            # Use default
          end

          if current_user.status == "active"
            session[:referer] = referer
            successful_login(current_user)
          else
            session[:token] = current_user.tokens.create.token
            UserMailer.signup_confirm(current_user, current_user.tokens.create(:referer => referer)).deliver_later
            redirect_to :controller => :confirmations, :action => :confirm, :display_name => current_user.display_name
          end
        else
          render :action => "new", :referer => params[:referer]
        end
      end
    end
  end

  def go_public
    current_user.data_public = true
    current_user.save
    flash[:notice] = t ".flash success"
    redirect_to edit_account_path
  end

  ##
  # sets a user's status
  def set_status
    @user.activate! if params[:event] == "activate"
    @user.confirm! if params[:event] == "confirm"
    @user.unconfirm! if params[:event] == "unconfirm"
    @user.hide! if params[:event] == "hide"
    @user.unhide! if params[:event] == "unhide"
    @user.unsuspend! if params[:event] == "unsuspend"
    redirect_to user_path(:display_name => params[:display_name])
  end

  ##
  # omniauth success callback
  def auth_success
    auth_info = request.env["omniauth.auth"]

    provider = auth_info[:provider]
    uid = auth_info[:uid]
    name = auth_info[:info][:name]
    email = auth_info[:info][:email]

    email_verified = case provider
                     when "openid"
                       uid.match(%r{https://www.google.com/accounts/o8/id?(.*)}) ||
                       uid.match(%r{https://me.yahoo.com/(.*)})
                     when "google", "facebook", "microsoft"
                       true
                     else
                       false
                     end

    if settings = session.delete(:new_user_settings)
      current_user.auth_provider = provider
      current_user.auth_uid = uid

      update_user(current_user, settings)

      flash.discard

      session[:user_errors] = current_user.errors.as_json

      redirect_to edit_account_path
    elsif session[:new_user]
      session[:new_user].auth_provider = provider
      session[:new_user].auth_uid = uid

      session[:new_user].activate if email_verified && email == session[:new_user].email

      redirect_to :action => "terms"
    else
      user = User.find_by(:auth_provider => provider, :auth_uid => uid)

      if user.nil? && provider == "google"
        openid_url = auth_info[:extra][:id_info]["openid_id"]
        user = User.find_by(:auth_provider => "openid", :auth_uid => openid_url) if openid_url
        user&.update(:auth_provider => provider, :auth_uid => uid)
      end

      if user
        case user.status
        when "pending"
          unconfirmed_login(user)
        when "active", "confirmed"
          successful_login(user, request.env["omniauth.params"]["referer"])
        when "suspended"
          failed_login({ :partial => "sessions/suspended_flash" })
        else
          failed_login t("sessions.new.auth failure")
        end
      else
        redirect_to :action => "new", :nickname => name, :email => email,
                    :auth_provider => provider, :auth_uid => uid
      end
    end
  end

  ##
  # omniauth failure callback
  def auth_failure
    flash[:error] = t(params[:message], :scope => "users.auth_failure", :default => t(".unknown_error"))

    origin = safe_referer(params[:origin]) if params[:origin]

    redirect_to origin || login_url
  end

  private

  ##
  # ensure that there is a "user" instance variable
  def lookup_user_by_name
    @user = User.find_by(:display_name => params[:display_name])
  rescue ActiveRecord::RecordNotFound
    redirect_to :action => "view", :display_name => params[:display_name] unless @user
  end

  ##
  # return permitted user parameters
  def user_params
    params.require(:user).permit(:email, :email_confirmation, :display_name,
                                 :auth_provider, :auth_uid,
                                 :pass_crypt, :pass_crypt_confirmation)
  end

  ##
  # check signup acls
  def check_signup_allowed(email = nil)
    domain = if email.nil?
               nil
             else
               email.split("@").last
             end

    mx_servers = if domain.nil?
                   nil
                 else
                   domain_mx_servers(domain)
                 end

    blocked = Acl.no_account_creation(request.remote_ip, :domain => domain, :mx => mx_servers)

    blocked ||= SIGNUP_IP_LIMITER && !SIGNUP_IP_LIMITER.allow?(request.remote_ip)

    blocked ||= email && SIGNUP_EMAIL_LIMITER && !SIGNUP_EMAIL_LIMITER.allow?(canonical_email(email))

    if blocked
      logger.info "Blocked signup from #{request.remote_ip} for #{email}"

      render :action => "blocked"
    end

    !blocked
  end

  def canonical_email(email)
    local_part, domain = if email.nil?
                           nil
                         else
                           email.split("@")
                         end

    local_part.sub!(/\+.*$/, "")

    local_part.delete!(".") if %w[gmail.com googlemail.com].include?(domain)

    "#{local_part}@#{domain}"
  end

  ##
  # get list of MX servers for a domains
  def domain_mx_servers(domain)
    Resolv::DNS.open do |dns|
      dns.getresources(domain, Resolv::DNS::Resource::IN::MX).collect { |mx| mx.exchange.to_s }
    end
  end
end