# See Pagy API documentation: https://ddnexus.github.io/pagy/api/pagy require 'pathname' class Pagy ; VERSION = '0.6.0' autoload :Backend, 'pagy/backend' autoload :Frontend, 'pagy/frontend' class OutOfRangeError < StandardError; end # root pathname to get the path of pagy files like templates or dictionaries def self.root; Pathname.new(__FILE__).dirname end # default core vars VARS = { items:20, outset:0, size:[1,4,4,1] } # default I18n vars I18N = { file: Pagy.root.join('locales', 'pagy.yml').to_s, plurals: -> (c) {c==0 && 'zero' || c==1 && 'one' || 'other'} } attr_reader :count, :page, :items, :vars, :pages, :last, :offset, :from, :to, :prev, :next # merge and validate the options, do some simple aritmetic and set the instance variables def initialize(vars) @vars = VARS.merge(vars) # default vars + instance vars @vars[:page] = (@vars[:page]||1).to_i # set page to 1 if nil { count:0, items:1, outset:0, page:1 }.each do |k,min| # validate core variables @vars[k] >= min rescue nil || raise(ArgumentError, "expected :#{k} >= #{min}; got #{@vars[k].inspect}") instance_variable_set(:"@#{k}", @vars.delete(k)) # set instance variables end @pages = @last = [(@count.to_f / @items).ceil, 1].max # cardinal and ordinal meanings (1..@last).cover?(@page) || raise(OutOfRangeError, "expected :page in 1..#{@last}; got #{@page.inspect}") @offset = @items * (@page - 1) + @outset # pagination offset + outset (initial offset) @items = @count % @items if @page == @last # adjust items for last page @from = @count == 0 ? 0 : @offset+1 - @outset # page begins from item @to = @offset + @items - @outset # page ends to item @prev = (@page-1 unless @page == 1) # nil if no prev page @next = (@page+1 unless @page == @last) # nil if no next page end # return the array of page numbers and :gap items e.g. [1, :gap, 7, 8, "9", 10, 11, :gap, 36] def series(size=@vars[:size]) (0..3).each{|i| size[i]>=0 rescue nil || raise(ArgumentError, "expected 4 items in :size >= 0; got #{size.inspect}")} series = [] [*0..size[0], *@page-size[1]..@page+size[2], *@last-size[3]+1..@last+1].sort!.each_cons(2) do |a, b| if a<0 || a==b || a>@last # skip out of range and duplicates elsif a+1 == b; series.push(a) # no gap -> no additions elsif a+2 == b; series.push(a, a+1) # 1 page gap -> fill with missing page else series.push(a, :gap) # n page gap -> add :gap end # skip the end boundary (last+1) end # shift the start boundary (0) and series.tap{|s| s.shift; s[s.index(@page)] = @page.to_s} # convert the current page to String end end