#-- encoding: UTF-8
#-- copyright
# OpenProject is a project management system.
# Copyright (C) 2012-2018 the OpenProject Foundation (OPF)
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License version 3.
#
# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
# Copyright (C) 2006-2017 Jean-Philippe Lang
# Copyright (C) 2010-2013 the ChiliProject Team
#
# 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 2
# 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
# See docs/COPYRIGHT.rdoc for more details.
#++

class SearchController < ApplicationController
  include Concerns::Layout

  before_action :find_optional_project

  def index
    @question = search_params[:q] || ''
    @question.strip!
    @all_words = search_params[:all_words] || !search_params[:submit]
    @titles_only = !search_params[:titles_only].nil?

    projects_to_search =
      case search_params[:scope]
      when 'all'
        nil
      when 'my_projects'
        User.current.memberships.map(&:project)
      when 'current_project'
        @project
      else
        @project ? (@project.self_and_descendants.active) : nil
      end

    offset = begin
      Time.at(Rational(search_params[:offset])) if search_params[:offset]
    rescue; end

    # quick jump to an work_package
    scan_work_package_reference @question do |id|
      return redirect_to work_package_path(id: id) if WorkPackage.visible.find_by(id: id.to_i)
    end

    @object_types = Redmine::Search.available_search_types.dup
    if projects_to_search.is_a? Project
      # don't search projects
      @object_types.delete('projects')
      # only show what the user is allowed to view
      @object_types = @object_types.select { |o| User.current.allowed_to?("view_#{o}".to_sym, projects_to_search) }
    end

    @scope = @object_types.select { |t| search_params[t] }
    @scope = @object_types if @scope.empty?

    # extract tokens from the question
    # eg. hello "bye bye" => ["hello", "bye bye"]
    @tokens = scan_query_tokens @question
    # tokens must be at least 2 characters long
    @tokens = @tokens.uniq.select { |w| w.length > 1 }

    if @tokens.any?
      # no more than 5 tokens to search for
      @tokens.slice! 5..-1 if @tokens.size > 5

      @results = []
      @results_by_type = Hash.new { |h, k| h[k] = 0 }

      limit = 10
      @scope.each do |s|
        r, c = s.singularize.camelcase.constantize.search(@tokens, projects_to_search,
                                                          all_words: @all_words,
                                                          titles_only: @titles_only,
                                                          limit: (limit + 1),
                                                          offset: offset,
                                                          before: search_params[:previous].nil?)
        @results += r
        @results_by_type[s] += c
      end
      @results = @results.sort { |a, b| b.event_datetime <=> a.event_datetime }
      if search_params[:previous].nil?
        @pagination_previous_date = @results[0].event_datetime if offset && @results[0]
        if @results.size > limit
          @pagination_next_date = @results[limit - 1].event_datetime
          @results = @results[0, limit]
        end
      else
        @pagination_next_date = @results[-1].event_datetime if offset && @results[-1]
        if @results.size > limit
          @pagination_previous_date = @results[-(limit)].event_datetime
          @results = @results[-(limit), limit]
        end
      end
    else
      @question = ''
    end
    render layout: layout_non_or_no_menu
  end

  private

  def find_optional_project
    return true unless params[:project_id]
    @project = Project.find(params[:project_id])
    check_project_privacy
  rescue ActiveRecord::RecordNotFound
    render_404
  end

  def scan_query_tokens(query)
    query.scan(%r{((\s|^)"[\s\w]+"(\s|$)|\S+)}).map { |m| m.first.gsub(%r{(^\s*"\s*|\s*"\s*$)}, '') }
  end

  def scan_work_package_reference(query, &blk)
    query.match(/\A#?(\d+)\z/) && ((blk && blk.call($1)) || true)
  end

  def search_params
    @search_params ||= permitted_params.search
  end
end