Redmine

# encoding: utf-8

#

# Redmine - project management software

# Copyright (C) 2006-2014  Jean-Philippe Lang

#

# 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.

module Redmine

  module Pagination

    class Paginator

      attr_reader :item_count, :per_page, :page, :page_param

      def initialize(*args)

        if args.first.is_a?(ActionController::Base)

          args.shift

          ActiveSupport::Deprecation.warn "Paginator no longer takes a controller instance as the first argument. Remove it from #new arguments."

        end

        item_count, per_page, page, page_param = *args

        @item_count = item_count

        @per_page = per_page

        page = (page || 1).to_i

        if page < 1

          page = 1

        end

        @page = page

        @page_param = page_param || :page

      end

      def offset

        (page - 1) * per_page

      end

      def first_page

        if item_count > 0

          1

        end

      end

      def previous_page

        if page > 1

          page - 1

        end

      end

      def next_page

        if last_item < item_count

          page + 1

        end

      end

      def last_page

        if item_count > 0

          (item_count - 1) / per_page + 1

        end

      end

      def first_item

        item_count == 0 ? 0 : (offset + 1)

      end

      def last_item

        l = first_item + per_page - 1

        l > item_count ? item_count : l

      end

      def linked_pages

        pages = []

        if item_count > 0

          pages += [first_page, page, last_page]

          pages += ((page-2)..(page+2)).to_a.select {|p| p > first_page && p < last_page}

        end

        pages = pages.compact.uniq.sort

        if pages.size > 1

          pages

        else

          []

        end

      end

      def items_per_page

        ActiveSupport::Deprecation.warn "Paginator#items_per_page will be removed. Use #per_page instead."

        per_page

      end

      def current

        ActiveSupport::Deprecation.warn "Paginator#current will be removed. Use .offset instead of .current.offset."

        self

      end

    end

    # Paginates the given scope or model. Returns a Paginator instance and

    # the collection of objects for the current page.

    #

    # Options:

    #   :parameter     name of the page parameter

    #

    # Examples:

    #   @user_pages, @users = paginate User.where(:status => 1)

    #

    def paginate(scope, options={})

      options = options.dup

      finder_options = options.extract!(

        :conditions,

        :order,

        :joins,

        :include,

        :select

      )

      if scope.is_a?(Symbol) || finder_options.values.compact.any?

        return deprecated_paginate(scope, finder_options, options)

      end

      paginator = paginator(scope.count, options)

      collection = scope.limit(paginator.per_page).offset(paginator.offset).to_a

      return paginator, collection

    end

    def deprecated_paginate(arg, finder_options, options={})

      ActiveSupport::Deprecation.warn "#paginate with a Symbol and/or find options is depreceted and will be removed. Use a scope instead."

      klass = arg.is_a?(Symbol) ? arg.to_s.classify.constantize : arg

      scope = klass.scoped(finder_options)

      paginate(scope, options)

    end

    def paginator(item_count, options={})

      options.assert_valid_keys :parameter, :per_page

      page_param = options[:parameter] || :page

      page = (params[page_param] || 1).to_i

      per_page = options[:per_page] || per_page_option

      Paginator.new(item_count, per_page, page, page_param)

    end

    module Helper

      include Redmine::I18n

      # Renders the pagination links for the given paginator.

      #

      # Options:

      #   :per_page_links    if set to false, the "Per page" links are not rendered

      #

      def pagination_links_full(*args)

        pagination_links_each(*args) do |text, parameters, options|

          if block_given?

            yield text, parameters, options

          else

            link_to text, params.merge(parameters), options

          end

        end

      end

      # Yields the given block with the text and parameters

      # for each pagination link and returns a string that represents the links

      def pagination_links_each(paginator, count=nil, options={}, &block)

        options.assert_valid_keys :per_page_links

        per_page_links = options.delete(:per_page_links)

        per_page_links = false if count.nil?

        page_param = paginator.page_param

        html = ''

        if paginator.previous_page

          # \xc2\xab(utf-8) = «

          text = "\xc2\xab " + l(:label_previous)

          html << yield(text, {page_param => paginator.previous_page}, :class => 'previous') + ' '

        end

        previous = nil

        paginator.linked_pages.each do |page|

          if previous && previous != page - 1

            html << content_tag('span', '...', :class => 'spacer') + ' '

          end

          if page == paginator.page

            html << content_tag('span', page.to_s, :class => 'current page')

          else

            html << yield(page.to_s, {page_param => page}, :class => 'page')

          end

          html << ' '

          previous = page

        end

        if paginator.next_page

          # \xc2\xbb(utf-8) = »

          text = l(:label_next) + " \xc2\xbb"

          html << yield(text, {page_param => paginator.next_page}, :class => 'next') + ' '

        end

        html << content_tag('span', "(#{paginator.first_item}-#{paginator.last_item}/#{paginator.item_count})", :class => 'items') + ' '

        if per_page_links != false && links = per_page_links(paginator, &block)

          html << content_tag('span', links.to_s, :class => 'per-page')

        end

        html.html_safe

      end

      # Renders the "Per page" links.

      def per_page_links(paginator, &block)

        values = per_page_options(paginator.per_page, paginator.item_count)

        if values.any?

          links = values.collect do |n|

            if n == paginator.per_page

              content_tag('span', n.to_s)

            else

              yield(n, :per_page => n, paginator.page_param => nil)

            end

          end

          l(:label_display_per_page, links.join(', ')).html_safe

        end

      end

      def per_page_options(selected=nil, item_count=nil)

        options = Setting.per_page_options_array

        if item_count && options.any?

          if item_count > options.first

            max = options.detect {|value| value >= item_count} || item_count

          else

            max = item_count

          end

          options = options.select {|value| value <= max || value == selected}

        end

        if options.empty? || (options.size == 1 && options.first == selected)

          []

        else

          options

        end

      end

    end

  end

end