rfb.rb

require 'json'
require 'nokogiri'
require 'open-uri'

def find_complete_row(doc, i)
  prev = doc.at_css("#rgn_content4 tbody tr:nth-child(#{i.pred})").css('td').map(&:text)

  prev.size == 10 ? prev : find_complete_row(doc, i.pred)
end

html = open('http://wikiwiki.jp/kancolle/?%B2%FE%BD%A4%B9%A9%BE%B3')
doc  = Nokogiri::HTML.parse(html, nil, 'EUC-JP')

json = doc.css('#rgn_content4 tbody tr').map.with_index(1) {|tr, i|
  cells = tr.css('td').map(&:text)

  case cells.size
  when 10
    weapon, sun, mon, tue, wed, thu, fri, sun, ship, remarks = cells
  when 9
    prev    = find_complete_row(doc, i)
    weapon  = prev.first

    sun, mon, tue, wed, thu, fri, sun, ship, remarks = cells
  when 8
    prev    = find_complete_row(doc, i)
    weapon  = prev.first
    remarks = prev.last

    sun, mon, tue, wed, thu, fri, sun, ship = cells
  else
    raise cells.size
  end

  wdays = [sun, mon, tue, wed, thu, fri, sun].map.with_index {|o_x, i|
    o_x == '〇' ? true : false
  }

  {
    weapon:  weapon,
    wdays:   wdays,
    ship:    ship,
    remarks: remarks
  }
}

puts JSON.pretty_generate(json)