# From: http://www.ruby-forum.com/topic/135807
# Author: Nobuyoshi Nakada

class Hash
   def collate(h)
      raise ArgumentError unless h.is_a?(Hash)
      update(h) { |key, *values| values }
      #update(h) { |key, *values| values.flatten.uniq }
   end
end

h1 = {:a=>1, :b=>2 }
h2 = {:a=>3, :b=>4, :c=>5}
h1.collate(h2)
p h1, h2     
#=> {:b=>[2, 4], :a=>[1, 3], :c=>5}
#=> {:b=>4, :a=>3, :c=>5}

puts
h1 = {:a=>1, :b=>2 }
h2 = {:a=>3, :b=>4, :c=>5}
h2.collate(h1)
p h1, h2     
#=> {:b=>2, :a=>1}
#=> {:b=>[4, 2], :a=>[3, 1], :c=>5}

# The Array power set is stolen from http://snippets.dzone.com/posts/show/3524
class Array
  # Returns the "power set" for this Array. This means that an array with all
  # subsets of the array's elements will be returned.
  def power_set
    # the power set line is stolen from http://johncarrino.net/blog/2006/08/11/powerset-in-ruby/
    inject([[]]){|c,y|r=[];c.each{|i|r<<i;r<<i+[y]};r}
  end
end

class Hash
  def power_set
    # Returns the "power set" for this Hash. This means that a array with hashes of all
    # subsets of the hash's (key => value) pairs will be returned.
    # Example:
    # >> {:feedback_type=>"", :language_code=>"", :comment=>""}.power_set
    #
    # [{}, {:comment=>""}, {:language_code=>""}, {:language_code=>"", :comment=>""}, {:feedback_type=>""}, {:feedback_type=>"", :comment=>""}, {:feedback_type=>"", :language_code=>""}, {:feedback_type=>"", :language_code=>"", :comment=>""}]
    
    hash_to_array = self.to_a
    array_power_set = hash_to_array.power_set
    hash_power_set = array_power_set.collect { |pairs| pairs.inject({}) { |hash,pair| hash[pair[0]] = pair[1]; hash } }
    hash_power_set
  end
end

class Object
   def deep_clone
      Marshal.load(Marshal.dump(self))
   end
end


class Hash

   # From: http://www.sameshirteveryday.com/2007/09/23/ruby-get-full-history-all-parents-of-a-hash-node
   # Author: Alex Gorbatchev
   # for further recursive hash methods see: 
   # - http://snippets.dzone.com/posts/show/1908
   # - http://snippets.dzone.com/posts/show/4706
   
   def nested_key(desired_key, &block)

      return false unless Hash === self
      #return false unless self.is_a?(Hash)

      self.each_pair do |k,v|  
         if k == desired_key or v.nested_key(desired_key, &block)  
            yield(k,v)  
            return true  
         end  
      end  

      return false  
   end


   def deep_values(key)   # cf. http://snippets.dzone.com/posts/show/1908 

      hash = self.deep_clone
      ret = []

      begin

         ar = []
         result = hash.nested_key(key) { |k, v| ar << k }
         break unless result
         ar = ar.reverse

         hk = ""
         ar.size.times { |i| hk << "[ar[#{i}]]" }
         #str = "hash" << hk << " rescue nil"
         str = "hash" << hk 

         # get value for hash key hk
         ret << eval(str)

         # delete the hash key
         key_to_delete = [ar.pop]

         hk = ""
         ar.size.times { |i| hk << "[ar[#{i}]]" }
         str = "hash" << hk
         str = str << ".delete(key_to_delete.first)"
         eval(str)


      end while result

      hash.clear  # optional
      ret

   end


   def deep_delete(key)

      hash = self

      begin

         ar = []
         result = hash.nested_key(key) { |k, v| ar << k }
         break unless result
         ar = ar.reverse

         # delete the hash key
         key_to_delete = [ar.pop]

         hk = ""
         ar.size.times { |i| hk << "[ar[#{i}]]" }
         str = "hash" << hk
         str = str << ".delete(key_to_delete.first)"
         eval(str)

      end while result

   end

end



puts
hash = {  
  :level_1 => {  
    :level_2 => {  :search => 'test1',
      :level_3 => {  
        :search => 'test2', :level_4 => {:search => 'test3'}
      }  
    }  
  }  
}  


require 'pp'

p hash
puts

pp hash
puts

hash.nested_key(:search) { |k, v| puts "#{k}  ::  #{v.inspect}" }

# prints out...
# search  ::  "test1"
# level_2  ::  {:search=>"test1", :level_3=>{:search=>"test2", :level_4=>{:search=>"test3"}}}
# level_1  ::  {:level_2=>{:search=>"test1", :level_3=>{:search=>"test2", :level_4=>{:search=>"test3"}}}}

puts


puts "DEEP VALUES"
p hash.deep_values(:search)   #=> ["test1", "test2", "test3"]
puts

puts "DEEP VALUES DELETED"
hash.deep_delete(:search)
p hash   #=> {:level_1=>{:level_2=>{:level_3=>{:level_4=>{}}}}}
puts

puts "DEEP VALUES"
p hash.deep_values(:search)   #=> []

# Hash#deep_merge
# From: http://pastie.textmate.org/pastes/30372, Elliott Hird
# Source: http://gemjack.com/gems/tartan-0.1.1/classes/Hash.html
# This file contains extensions to Ruby and other useful snippits of code.
# Time to extend Hash with some recursive merging magic.


class Hash

  # Merges self with another hash, recursively.
  # 
  # This code was lovingly stolen from some random gem:
  # http://gemjack.com/gems/tartan-0.1.1/classes/Hash.html
  # 
  # Thanks to whoever made it.

  def deep_merge(hash)
    target = dup
    
    hash.keys.each do |key|
      if hash[key].is_a? Hash and self[key].is_a? Hash
        target[key] = target[key].deep_merge(hash[key])
        next
      end
      
      target[key] = hash[key]
    end
    
    target
  end


  # From: http://www.gemtacular.com/gemdocs/cerberus-0.2.2/doc/classes/Hash.html
  # File lib/cerberus/utils.rb, line 42

  def deep_merge!(second)
    second.each_pair do |k,v|
      if self[k].is_a?(Hash) and second[k].is_a?(Hash)
        self[k].deep_merge!(second[k])
      else
        self[k] = second[k]
      end
    end
  end


#-----------------
        
   # cf. http://subtech.g.hatena.ne.jp/cho45/20061122
   def deep_merge2(other)
      deep_proc = Proc.new { |k, s, o|
         if s.kind_of?(Hash) && o.kind_of?(Hash)
            next s.merge(o, &deep_proc)
         end
         next o
      }
      merge(other, &deep_proc)
   end


   def deep_merge3(second)

      # From: http://www.ruby-forum.com/topic/142809
      # Author: Stefan Rusterholz

      merger = proc { |key,v1,v2| Hash === v1 && Hash === v2 ? v1.merge(v2, &merger) : v2 }
      self.merge(second, &merger)

   end


   def keep_merge(hash)
      target = dup
      hash.keys.each do |key|
         if hash[key].is_a? Hash and self[key].is_a? Hash
            target[key] = target[key].keep_merge(hash[key])
            next
         end
         #target[key] = hash[key]
         target.update(hash) { |key, *values| values.flatten.uniq }
      end
      target
   end

end


h = {:a => {:b => :c}}.merge({:a => {:l => :x}})
p h  #=> {:a=>{:l=>:x}}

h = {:a => {:b => :c}}.deep_merge({:a => {:l => :x}})
p h  #=> {:a=>{:b=>:c, :l=>:x}}
puts


h1 = {:a => {:b => :c}}
h2 = {:a => {:l => :x}}

h = h1.deep_merge(h2)
p h1, h2, h
puts

h = h1.deep_merge2(h2)
p h1, h2, h
puts

h = h1.deep_merge!(h2)
p h1, h2, h


h1 = {:a => {:b => :c}}
h2 = {:a => {:l => :x}}

p h1.deep_merge3(h2)
p h1, h2


first = {
  :data=>{
    :name=>{
      :first=>'Sam',
      :middle=>'I',
      :last=>'am'
    }
  }
}

second={
  :data=>{
    :name=>{
      :middle=>'you',
      :last=>'are'
    }
  }
}


p first.deep_merge3(second)
#=> {:data=>{:name=>{:middle=>"you", :first=>"Sam", :last=>"are"}}}

p first.keep_merge(second)
#=>  {:data=>{:name=>{:first=>"Sam", :middle=>["I", "you"], :last=>["am", "are"]}}}

class Hash
  def rename_key(old_key, new_key)
    return Hash.rename_key(self.dup, old_key, new_key)
  end
  
  def rename_key!(old_key, new_key)
    return Hash.rename_key(self, old_key, new_key)
  end
  
  def all_values_empty?
    self.each_value do |v|
      return false if v and v != ""
    end
    
    return true
  end
  
  private
    def self.rename_key(hsh, old_key, new_key)
      hsh[new_key.to_s] = hsh.delete(old_key.to_s)
      return hsh
    end
end

class Array
  
  # Make a hash of arrays out of an array
  # of somethings by involving each element.
  #
  # Pass a block returning each keys' name.
  #
  # Example usage:
  #
  # >> [1, 2, 3].to_hoa { |n| (n+96).chr }
  # => {"a"=>[1], "b"=>[2], "c"=>[3]}
  #
  # >> ['a', 'a', 'a', 'b', 'b', 'c'].to_hoa {|x|x}
  # => {"a"=>["a", "a", "a"], "b"=>["b", "b"], "c"=>["c"]}
    
  def to_hoa
    inject({}) { |h,v| (h[yield(v)] ||= []).push v; h }
  end

end

# From: http://www.ruby-forum.com/topic/111524
# Author: Daniel Martin

a = Hash.new{|h,k| h[k]=Hash.new(&h.default_proc) }

a[2][1]=2
a[2][2][3]=4
a[3][1][1][1]=1

p  a     #=> {2=>{1=>2, 2=>{3=>4}}, 3=>{1=>{1=>{1=>1}}}}


# From: http://www.ruby-forum.com/topic/130324
# Author: Bob Hutchison

class Hash
   def Hash.new_nested_hash
     Hash.new{|h,k| h[k]=Hash.new(&h.default_proc) }
   end
end

a = Hash.new_nested_hash

a[2][1]=2
a[2][2][3]=4
a[3][1][1][1]=1

p  a     #=> {2=>{1=>2, 2=>{3=>4}}, 3=>{1=>{1=>{1=>1}}}}


# From: http://www.rubyquiz.com/quiz113.html
# Author: Carl Porth

ar = ('a'..'g').to_a
p  ar.reverse.inject { |mem, var| {var => mem} }    #=> {"a"=>{"b"=>{"c"=>{"d"=>{"e"=>{"f"=>"g"}}}}}}

class Hash
  @keys_not_used = nil

  def random_key
          @keys_not_used = self.dup if (!@keys_not_used or @keys_not_used.size == 0)
	  key = @keys_not_used.keys[rand(@keys_not_used.size)]
	  @keys_not_used.delete(key)
          key
  end

end

require 'csv'

csv_data = CSV.read 'data.csv'
headers = csv_data.shift.map {|i| i.to_s }
string_data = csv_data.map {|row| row.map {|cell| cell.to_s } }
array_of_hashes = string_data.map {|row| Hash[*headers.zip(row).flatten] }