class FilterPage < Page

  include Radiant::Taggable

  class TagError < StandardError; end

  description %{ Special Page for collecting model filters. }

  desc %{ }
  tag 'filters' do |tag|
    tag.locals.filters =  tag.globals.page.filters
    tag.locals.ops     =  tag.globals.page.ops
    tag.expand
  end

  desc %{ }
  tag 'filters:rel_url' do |tag|
    tag.globals.page.rel_url
  end

  desc %{ }
  tag 'filters:each' do |tag|
    if tag.locals.filters && tag.locals.filters.size>0
      result = []
      tag.locals.filters.each do |field,value|
        tag.locals.field = field
        tag.locals.value = value
        tag.locals.op = tag.locals.ops[field] || '='
        result << tag.expand
      end
      result
    end
  end

  desc %{ }
  tag 'filters:count' do |tag|
    if tag.locals.filters
      tag.locals.filters.size.to_s
    else
      "0"
    end
  end

  desc %{ }
  tag 'filters:conditions' do |tag|
    sqlfilter = ""
    if tag.locals.filters && tag.locals.filters.size > 0
      tag.locals.filters.each do |field,value|
        op = tag.locals.ops[field] if (tag.locals.ops && field && value)
        if op && field && value
          if sqlfilter.size != 0
            sqlfilter += " AND "
          end
          if op == 'Starts'
            sqlfilter += "#{field} LIKE '#{value}%'"
          elsif op == 'Ends'
            sqlfilter += "#{field} LIKE '%#{value}'"
          elsif op == 'Contains'
            sqlfilter += "#{field} LIKE '%#{value}%'"
          elsif op == 'Is null'
            sqlfilter += "(#{field} is null OR length(#{field})=0)"
          elsif op == 'Not null'
            sqlfilter += "(#{field} is not null AND length(#{field})>0)"
          else
            sqlfilter += "#{field} #{op} '#{value}'"
          end
        end
      end
    end
    tag.locals.conditions = sqlfilter
    tag.expand
  end

  desc %{ }
  tag "filters:if_field" do |tag|
    field = tag.attr['name'] || ""
    if tag.locals.filters && tag.locals.filters[field]
      tag.expand
    end
  end

  desc %{ }
  tag "filters:unless_field" do |tag|
    field = tag.attr['name'] || ""
    unless tag.locals.filters && tag.locals.filters[field]
      tag.expand
    end
  end

  desc %{ }
  tag 'filters:conditions:show' do |tag|
    tag.locals.conditions
  end

  desc %{ }
  tag 'filters:each:field' do |tag|
    tag.locals.field
  end

  desc %{ }
  tag 'filters:each:value' do |tag|
    tag.locals.value
  end

  desc %{ }
  tag 'filters:each:op' do |tag|
    tag.locals.op
  end

  def virtual?
    true
  end

  attr_reader :filters
  attr_reader :ops
  attr_reader :rel_url

  def find_by_url(url, live = true, clean = false)
    @filters = Hash.new
    @ops = Hash.new
    ops_table = {
        'e'=>'=',       'g'=>'>',       'G'=>'>=',              'l'=>'<',       'L'=>'<=',
        'a'=> 'Starts', 'z'=>'Ends',    'c'=>'Contains',        'n'=>'Is null', 'N'=>'Not null'  }
    url = clean_url(url) if clean
    if url =~ %r{#{ self.url }(((\w{1,50}:\w:[^\'\"]{1,100})/?){1,8})/?$}
      filterstr = $1
      @rel_url = ""
      h = Hash.new
      tmp = filterstr.split('/') if filterstr
      tmp.each do |t|
        field, op, value = t.split(':',3)
        @filters[field] = value if (field && value)
        @ops[field] = ops_table[op] if (field && op && ops_table[op])
        h[field] = t
      end
      h.each { |k,v| @rel_url += "#{v}/" }
      self
    else
      super
    end
  end
end