Parse WXDATA files to extract snowfall totals

wxdata.rb

def parse file_name
  lines = File.readlines(file_name)
  # puts "#{file_name} has #{lines.size} lines"
  lines[4] =~ /.*: (\d+)/
  data_id = $1.to_i
  monthly_data(data_id, lines)
rescue => e
  puts "Error with file #{file_name}: #{e}"
  [data_id]
end

def snow_table_row(lines)
  [40, 46].detect {|row| puts "'#{lines[row]}'"; lines[row] =~ /Snow Table/ }
end

def annual_data(data_id, lines)
  raise 'No snow table' if snow_table_row(lines).nil?
  
  annual_row = snow_table_row(lines) + 14
  
  data = lines[annual_row].split ' '
  raise 'Line #{annual_row} is not the ann row' unless data[0] == 'Ann'
  data[0] = data_id
  data
end

def monthly_data(data_id, lines)
  raise 'No snow table' if snow_table_row(lines).nil?

  jan_row = snow_table_row(lines) + 2
  monthly_snow_data = lines[jan_row, 12]
  monthly_snow = monthly_snow_data.map do |line|
    line.split(' ')[1]
  end

  [data_id] + monthly_snow
end


def parse_all
  Dir['wxdata/*.txt'].map do |file|
    parse file
  end
end

def wxdata
  File.open('wxdata.csv', 'w') do |f| 
    data = parse_all
    data.each do |row|
      f.puts row.join("\t")
    end
  end
end