module Sp500

# File lib/sp500.rb, line 77
def by_industries
  result = {}

  list.each do |stock| 
    result[stock.gics_sector] ||= {}
    result[stock.gics_sector][stock.gics_sub_industry] ||= []
    result[stock.gics_sector][stock.gics_sub_industry] << stock
  end

  result
end

# File lib/sp500.rb, line 66
def by_sectors
  result = {}

  list.each do |stock|
    result[stock.gics_sector] ||= []
    result[stock.gics_sector] << stock
  end

  result
end

# File lib/sp500.rb, line 55
def industries
  result = {}

  list.each do |stock| 
    result[stock.gics_sector] ||= []
    result[stock.gics_sector] << stock.gics_sub_industry unless result[stock.gics_sector].include?(stock.gics_sub_industry)
  end

  result
end

# File lib/sp500.rb, line 15
def list
  doc = Nokogiri::HTML(open("https://en.wikipedia.org/wiki/List_of_S%26P_500_companies"))

  doc.at_xpath("//div[@id='mw-content-text']//table[contains(@class,'wikitable')]").search('tr').map do |row|
    cells = row.search('td').map do |cell| 
      if cell.search('a').length > 0
        [
          cell.search('a')[0].text.strip, 
          cell.search('a')[0]['href']
        ]
      else
        cell.text.strip
      end
    end

    next if cells.empty?

    Stock.new(
      ticker_symbol: cells[0][0],
      nyse_quote_url: cells[0][1],
      firm_name: cells[1][0],
      firm_wikipedia_url: cells[1][1],
      sec_filling_type: cells[2][0],
      sec_fillings_doc_url: cells[2][1],
      gics_sector: cells[3],
      gics_sub_industry: cells[4],
      firm_hq_address: cells[5][0],
      firm_hq_address_url: cells[5][1],
      sp500_introduction_date: (cells[6].blank? ? 'n/a' : Date.parse(cells[6])),
      central_index_key: cells[7]
    )
  end.compact
end

# File lib/sp500.rb, line 49
def sectors
  list.map do |stock| 
    stock.gics_sector
  end.uniq.sort
end