7L7W Ruby - Day 3

ruby_day3.rb

=begin
Modify the CSV application to support an each method to return a
CsvRow object. Use method_missing on that CsvRow to return the value
for the column for a given heading.

For example, for the file:
one, two
lions, tigers
allow an API that works like this:
csv = RubyCsv.new
csv.each {|row| puts row.one}
This should print "lions".
=end

module ActsAsCsv
	def self.included(base)
		base.extend ClassMethods
	end
	
	module ClassMethods
		def acts_as_csv
			include InstanceMethods
			include Enumerable
		end
	end
	
	module InstanceMethods
		def read
			@csv_contents = []
			filename = self.class.to_s.downcase + '.txt'
			file = File.new(filename)
			@headers = file.gets.chomp.split(', ' )
			file.each do |row|
				@csv_contents << CsvRow.new(headers, row.chomp.split(', ' ))
			end
		end
	
		attr_accessor :headers, :csv_contents
		
		def initialize
			read
		end
		
		def each &blk
			@csv_contents.each &blk
		end
	end
end

class CsvRow
	attr_accessor :headers, :csv_contents
	
	def initialize(headers=[], csv_contents=[])
		@csv_contents = csv_contents
		@headers = headers
	end
	
	def method_missing name, *args
		csv_contents[headers.index(name.to_s)]
	end	
end

class RubyCsv # no inheritance! You can mix it in
	include ActsAsCsv
	acts_as_csv
end

m = RubyCsv.new
puts m.headers.inspect
puts m.csv_contents.inspect
puts
puts

csv = RubyCsv.new
csv.each {|row| puts row.one}