require 'magic_grid/definition'
require 'will_paginate/array'

module MagicGrid
  module Helpers
    def normalize_magic(collection, columns = [], options = {})
      if collection.is_a? MagicGrid::Definition
        collection
      elsif columns.is_a? MagicGrid::Definition
        columns
      elsif options.is_a? MagicGrid::Definition
        options
      else
        MagicGrid::Definition.new(columns, collection, controller, options)
      end
    end

    def magic_collection(collection, cols, opts = {})
      normalize_magic(collection, cols, opts).collection
    end

    def magic_grid(collection = nil, cols = nil, opts = {}, &block)
      grid = normalize_magic(collection, cols, opts)
      base_params = grid.base_params
      data = {
        :searcher => grid.options[:searcher],
        :current => url_for,
        :live_search => grid.options[:live_search],
        :listeners => (grid.options[:listeners] unless grid.options[:listeners].empty?),
        :remote => grid.options[:remote],
        :default_ajax_handler => grid.options[:default_ajax_handler],
        :params => base_params,
      }
      classes = ['magic_grid'] << grid.options[:class]
      content_tag('table',
                  :class => classes.join(' '),
                  :id => grid.magic_id,
                  :data => data.select {|_,v| v }
                  ) do
        table = content_tag('thead', :data => {:params => base_params}
                           ) do
          thead = ''.html_safe
          has_spinner = false
          spinner = tag('span',
                        :id => (grid.magic_id.to_s + "_spinner"),
                        :class => "magic_grid_spinner"
                       )
          if grid.options[:needs_searcher]
            thead << content_tag('tr') do
              content_tag('td', :class => 'searcher full-width ui-widget-header',
                          :colspan => grid.columns.count) do
                searcher_data = {
                  :min_length => grid.options[:min_search_length],
                  :current => grid.options[:current_search] || "",
                }
                searcher = label_tag(grid.options[:searcher].to_sym,
                                     grid.options[:searcher_label])
                searcher << search_field_tag(grid.options[:searcher].to_sym,
                                             grid.param(:q),
                                             :placeholder => grid.options[:searcher_tooltip],
                                             :size => grid.options[:searcher_size],
                                             :data => searcher_data,
                                             :form => "a form that doesn't exist")
                if grid.options[:search_button]
                  searcher << button_tag(grid.options[:searcher_button],
                                         :class => 'magic-grid-search-button')
                end
                unless has_spinner
                  has_spinner = true
                  searcher << spinner
                end
                searcher
              end
            end
          end
          if grid.options[:per_page] and grid.options[:top_pager]
            thead << content_tag('tr') do
              content_tag('td', :class => 'full-width ui-widget-header',
                          :colspan => grid.columns.count) do
                pager = will_paginate(grid.collection,
                                      :param_name => grid.param_key(:page),
                                      :params => base_params
                                     )
                unless has_spinner
                  has_spinner = true
                  pager << spinner
                end
                pager
              end
            end
          end
          if thead.empty? and not grid.options[:empty_header]
            thead = content_tag 'tr' do
              content_tag('td', :class => 'full-width ui-widget-header',
                          :colspan => grid.columns.count) do
                unless has_spinner
                  has_spnner = true
                  spinner
                end
              end
            end
          end
          thead << magic_headers(grid)
        end
        table << content_tag('tbody', :class => "ui-widget-content") do
          magic_rows(grid, &block)
        end
        table << content_tag('tfoot') do
          tfoot = ''.html_safe
          if grid.options[:per_page] and grid.options[:bottom_pager]
            tfoot << content_tag('tr') do
              content_tag('td', :class => 'full-width ui-widget-header',
                          :colspan => grid.columns.count) do
                will_paginate(grid.collection,
                              :param_name => grid.param_key(:page),
                              :params => base_params
                             )
              end
            end
          end
          if tfoot.empty? and not grid.options[:empty_footer]
            tfoot = content_tag 'tr' do
              content_tag('td', nil, :class => 'full-width ui-widget-header',
                          :colspan => grid.columns.count)
            end
          end
          tfoot
        end
      end
    end

    def magic_headers(cols, collection = nil, opts = {})
      grid = normalize_magic(collection, cols, opts)
      content_tag 'tr' do
        grid.columns.reduce(''.html_safe) do |acc, col|
          classes = ['ui-state-default'] << col[:class]
          acc <<
          if col.is_a? String
            content_tag 'th', col.html_safe, :class => classes.join(' ')
          elsif not col.key? :sql
            content_tag 'th', col[:label].html_safe, :class => classes.join(' ')
          else
            sortable_header(grid, col, opts)
          end
        end
      end
    end

    def magic_rows(cols, collection = nil, &block)
      grid = normalize_magic(collection, cols)
      if_empty = grid.options[:if_empty]
      rows = grid.collection.map do |row|
        if block_given?
          "<!-- block: -->" << capture(row, &block)
        else
          "<!-- magic row: -->" << magic_row(row, grid)
        end
      end
      if rows.empty? and if_empty
        content_tag 'tr' do
          content_tag('td', :colspan => grid.columns.count,
                      :class => 'if-empty') do
            if if_empty.respond_to? :call
              if_empty.call(grid).to_s
            else
              if_empty
            end
          end
        end
      else
        rows.join.html_safe
      end
    end

    def magic_row(record, cols, collection = nil)
      grid = normalize_magic(collection, cols)
      content_tag 'tr', :class => cycle('odd', 'even') do
        grid.columns.reduce(''.html_safe) do |acc, c|
          acc << content_tag('td', :class => c[:class].try(:join, ' ')) do
            method = c[:to_s] || c[:col]
            if method.respond_to? :call
              method.call(record)
            elsif record.respond_to? method
              record.send(method)
            end.to_s
          end
        end
      end
    end

    def reverse_order(order)
      order.to_i == 0 ? 1 : 0
    end

    def order_icon(order = -1)
      content_tag 'span', '', :class => "ui-icon #{order_icon_class(order)}"
    end

    def order_icon_class(order = -1)
      case order.to_i
      when 0 then 'ui-icon-triangle-1-n'
      when 1 then 'ui-icon-triangle-1-s'
      else 'ui-icon-carat-2-n-s'
      end
    end

    def order_class(order = -1)
      case order.to_i
      when 0 then 'sort-asc'
      when 1 then 'sort-desc'
      else 'sort-none'
      end
    end

    def sortable_header(grid, col, opts = {})
      id = col[:id]
      label = col[:label] || id.titleize
      default_sort_order = opts.fetch(:default_order, grid.order(grid.default_order))
      my_params = grid.base_params.merge({
        grid.param_key(:col) => id,
      })
      my_params = HashWithIndifferentAccess.new(my_params)
      order = nil
      classes = ['sorter ui-state-default'] << col[:class]
      current = id.to_s == grid.current_sort_col.to_s
      if current
        order = grid.current_order
        classes << "sort-current" << order_class(order)
        my_params[grid.param_key(:order)] = reverse_order(order)
        label << order_icon(order)
      else
        my_params.delete grid.param_key(:order) if my_params[grid.param_key(:order)]
        label << order_icon()
      end
      my_params.delete(grid.param_key(:order)) if my_params[grid.param_key(:order)].to_i == default_sort_order.to_i
      content_tag 'th', :class => classes.join(' ') do
        link_to label.html_safe, my_params, :remote => grid.options[:remote]
      end
    end

    ::ActionView::Base.send :include, self
  end
end