diff --git a/.rspec b/.rspec
new file mode 100644
index 0000000..35f4d74
--- /dev/null
+++ b/.rspec
@@ -0,0 +1,2 @@
+--color
+--format Fuubar
diff --git a/bin/sudoku-validator b/bin/sudoku-validator
new file mode 100755
index 0000000..9e245f5
--- /dev/null
+++ b/bin/sudoku-validator
@@ -0,0 +1,9 @@
+#!/usr/bin/env ruby
+
+require './lib/sudoku_reader'
+require './lib/sudoku_validator'
+
+reader = SudokuReader.new(ARGV.first)
+validator = SudokuValidator.new(reader)
+
+puts validator.message
diff --git a/invalid_block.sudoku b/invalid_block.sudoku
new file mode 100644
index 0000000..8ed3bd8
--- /dev/null
+++ b/invalid_block.sudoku
@@ -0,0 +1,11 @@
+8 5 9 |6 1 2 |4 3 7
+7 2 3 |8 5 4 |1 6 9
+1 6 4 |3 7 9 |5 2 8
+------+------+------
+9 8 6 |1 4 7 |3 5 2
+3 7 . |2 6 8 |9 1 4
+2 4 1 |5 9 3 |7 8 6
+------+------+------
+4 3 5 |9 8 1 |6 7 .
+6 1 7 |4 2 5 |8 9 3
+5 9 8 |7 3 6 |2 4 1
diff --git a/invalid_column.sudoku b/invalid_column.sudoku
new file mode 100644
index 0000000..fb651a7
--- /dev/null
+++ b/invalid_column.sudoku
@@ -0,0 +1,11 @@
+8 5 9 |6 1 2 |4 3 7
+7 2 3 |8 5 4 |1 6 9
+1 6 4 |3 7 9 |5 2 8
+------+------+------
+9 8 6 |1 4 7 |3 5 2
+3 7 5 |8 6 2 |9 1 4
+2 4 1 |5 9 3 |7 8 6
+------+------+------
+4 3 2 |9 8 1 |6 7 5
+6 1 7 |4 2 5 |8 9 3
+5 9 8 |7 3 6 |2 4 1
diff --git a/invalid_line.sudoku b/invalid_line.sudoku
new file mode 100644
index 0000000..6500ea7
--- /dev/null
+++ b/invalid_line.sudoku
@@ -0,0 +1,11 @@
+8 5 9 |6 5 2 |4 3 7
+7 2 3 |8 1 4 |1 6 9
+1 6 4 |3 7 9 |5 2 8
+------+------+------
+9 8 6 |1 4 7 |3 5 2
+3 7 5 |2 6 8 |9 1 4
+2 4 1 |5 9 3 |7 8 6
+------+------+------
+4 3 2 |9 8 1 |6 7 5
+6 1 7 |4 2 5 |8 9 3
+5 9 8 |7 3 6 |2 4 1
diff --git a/lib/sudoku_reader.rb b/lib/sudoku_reader.rb
new file mode 100644
index 0000000..f2d980b
--- /dev/null
+++ b/lib/sudoku_reader.rb
@@ -0,0 +1,91 @@
+class SudokuReader
+  attr_reader :path
+
+  def initialize(path)
+    @path = path
+    @lines = []
+    @blocks = []
+  end
+
+  def lines
+    return @lines if @lines.any?
+    File.read(path).each_line {|line| convert_line_to_values(line)}
+    @lines
+  end
+
+  def each_line
+    lines.each_with_index {|line, index| yield(line, index)}
+  end
+
+  def each_value_by_line
+    each_line {|line, index| line.each{|value| yield(line, value, index)}}
+  end
+
+  def each_value_by_column
+    columns.each_with_index do |column, index|
+      column.each{|value| yield(column, value, index)}
+    end
+  end
+
+  def each_value_by_block
+    blocks.each_with_index do |block, index|
+      block.each{|value| yield(block, value, index)}
+    end
+  end
+
+  def columns
+    @columns ||= lines.transpose
+  end
+
+  def blocks
+    return @blocks if @blocks.any?
+    init_empty_blocks
+    fill_blocks
+    @blocks
+  end
+
+  private
+  def fill_blocks
+    each_block do |block_number|
+      line, column = block_start(block_number)
+      each_line_in_block {|k| get_line_of_block(line, column, k)}
+    end
+  end
+
+  def block_start(block_number)
+    row = ((block_number) / 3) * 3
+    col = ((block_number) % 3) * 3
+    [row,col]
+  end
+
+  def get_line_of_block(vertical_start, horizontal_start, line_block)
+    line = lines[horizontal_start + line_block]
+    line_in_block = line.drop(vertical_start).first(3)
+    index_of_block = vertical_start + horizontal_start/3
+    @blocks[index_of_block] += line_in_block
+  end
+
+  def each_block
+    9.times {|block_number| yield(block_number)}
+  end
+
+  def each_line_in_block
+    3.times {|index_line_of_block| yield(index_line_of_block)}
+  end
+
+  def init_empty_blocks
+    9.times { @blocks << [] }
+  end
+
+  def convert_line_to_values(line)
+    @lines << line.split.map { |value| sanitize(value) } unless separator?(line)
+  end
+
+  def separator?(line)
+    line == "------+------+------\n"
+  end
+
+  def sanitize(value)
+    value.gsub('|','').to_i
+  end
+end
diff --git a/lib/sudoku_validator.rb b/lib/sudoku_validator.rb
new file mode 100644
index 0000000..cbb92b2
--- /dev/null
+++ b/lib/sudoku_validator.rb
@@ -0,0 +1,51 @@
+class SudokuValidator
+  attr_accessor :reader
+
+  def initialize(reader)
+    @reader = reader
+    @errors = []
+  end
+
+  def complete?
+    reader.each_line {|line| return false if line.include?(0)}
+    return true
+  end
+
+  def valid?
+    lines_valid? && columns_valid? && blocks_valid?
+  end
+
+  def message
+    if valid?
+      "This sudoku is valid#{complete_message}."
+    else
+      "This sudoku is invalid." + @errors.join
+    end
+  end
+
+  private
+  def complete_message
+    ", but incomplete" unless complete?
+  end
+
+  def lines_valid?
+    check_validity_for(:line)
+  end
+
+  def columns_valid?
+    check_validity_for(:column)
+  end
+
+  def blocks_valid?
+    check_validity_for(:block)
+  end
+
+  def check_validity_for(type)
+    reader.send("each_value_by_#{type}") do |row, value, index|
+      if row.count(value) > 1 && value != 0
+        @errors << "\n - There is multiple #{value} in #{type} #{index + 1}."
+      end
+    end
+    @errors.empty?
+  end
+end
diff --git a/spec/sudoku_reader_spec.rb b/spec/sudoku_reader_spec.rb
new file mode 100644
index 0000000..f0ec06d
--- /dev/null
+++ b/spec/sudoku_reader_spec.rb
@@ -0,0 +1,39 @@
+require_relative '../lib/sudoku_reader'
+
+describe SudokuReader do
+  describe "#lines" do
+    it "give lines" do
+      reader = SudokuReader.new('valid_complete.sudoku')
+      expect(reader.lines[0]).to eq [8,5,9,6,1,2,4,3,7]
+    end
+
+    it "convert invalid values by 0" do
+      reader = SudokuReader.new('valid_incomplete.sudoku')
+      expect(reader.lines[0]).to eq [8,5,0,0,0,2,4,0,0]
+    end
+  end
+
+  describe "#columns" do
+    it "give columns" do
+      reader = SudokuReader.new('valid_complete.sudoku')
+      expect(reader.columns[0]).to eq [8,7,1,9,3,2,4,6,5]
+    end
+
+    it "convert invalid values by 0" do
+      reader = SudokuReader.new('valid_incomplete.sudoku')
+      expect(reader.columns[0]).to eq [8,7,0,0,3,0,0,0,0]
+    end
+  end
+
+  describe "#blocks" do
+    it "give blocks" do
+      reader = SudokuReader.new('valid_complete.sudoku')
+      expect(reader.blocks[0]).to eq [8,5,9,7,2,3,1,6,4]
+    end
+
+    it "convert invalid values by 0" do
+      reader = SudokuReader.new('valid_incomplete.sudoku')
+      expect(reader.blocks[0]).to eq [8,5,0,7,2,0,0,0,4]
+    end
+  end
+end
diff --git a/spec/sudoku_validator_spec.rb b/spec/sudoku_validator_spec.rb
new file mode 100644
index 0000000..2d8333a
--- /dev/null
+++ b/spec/sudoku_validator_spec.rb
@@ -0,0 +1,81 @@
+require_relative '../lib/sudoku_validator'
+require_relative '../lib/sudoku_reader.rb'
+
+describe SudokuValidator do
+  describe "#complete?" do
+    context "with complete sudokus" do
+      it "give true" do
+        ['valid_complete.sudoku', 'invalid_complete.sudoku'].each do |file|
+          expect(validator_for(file)).to be_complete
+        end
+      end
+    end
+
+    context "with incomplete sudokus" do
+      it "give false" do
+        ['valid_incomplete.sudoku', 'invalid_incomplete.sudoku'].each do |file|
+          expect(validator_for(file)).to_not be_complete
+        end
+      end
+    end
+  end
+
+  describe "#valid?" do
+    context "with valid sudokus" do
+      it "give true" do
+        ['valid_complete.sudoku', 'valid_incomplete.sudoku'].each do |file|
+          expect(validator_for(file)).to be_valid
+        end
+      end
+    end
+
+    context "with invalid sudokus" do
+      it "give true" do
+        ['invalid_complete.sudoku',
+         'invalid_incomplete.sudoku',
+         'invalid_column.sudoku',
+         'invalid_block.sudoku',
+         'invalid_line.sudoku'].each do |file|
+          expect(validator_for(file)).to_not be_valid
+        end
+      end
+    end
+  end
+
+  describe "#message" do
+    context "when the sudoku is valid" do
+      context "when the sudoku is complete" do
+        it "say than the sudoku is valid" do
+          file = 'valid_complete.sudoku'
+          expect(validator_for(file).message).to eq "This sudoku is valid."
+        end
+      end
+
+      context "when the sudoku is incomplete" do
+        it "say than the sudoku is valid" do
+          file = 'valid_incomplete.sudoku'
+          expect(validator_for(file).message).to eq "This sudoku is valid, but incomplete."
+        end
+      end
+    end
+
+    context "when the sudoku is invalid" do
+      it "say than the sudoku is invalid" do
+        ['invalid_complete.sudoku', 'invalid_incomplete.sudoku'].each do |file|
+          expect(validator_for(file).message).to match "This sudoku is invalid."
+        end
+      end
+
+      context "when the sudoku is invalid du to lines" do
+        it "say than there is an error in line" do
+          file = 'invalid_line.sudoku'
+          expect(validator_for(file).message).to match "There is multiple 5 in line 1."
+        end
+      end
+    end
+  end
+
+  def validator_for(file)
+    SudokuValidator.new(SudokuReader.new(file))
+  end
+end
diff --git a/valid_complete.sudoku b/valid_complete.sudoku
index ec5075c..0eab989 100644
--- a/valid_complete.sudoku
+++ b/valid_complete.sudoku
@@ -1,11 +1,11 @@
-8 5 9 |6 1 2 |4 3 7 
-7 2 3 |8 5 4 |1 6 9 
-1 6 4 |3 7 9 |5 2 8 
+8 5 9 |6 1 2 |4 3 7
+7 2 3 |8 5 4 |1 6 9
+1 6 4 |3 7 9 |5 2 8
 ------+------+------
-9 8 6 |1 4 7 |3 5 2 
-3 7 5 |2 6 8 |9 1 4 
-2 4 1 |5 9 3 |7 8 6 
+9 8 6 |1 4 7 |3 5 2
+3 7 5 |2 6 8 |9 1 4
+2 4 1 |5 9 3 |7 8 6
 ------+------+------
-4 3 2 |9 8 1 |6 7 5 
-6 1 7 |4 2 5 |8 9 3 
-5 9 8 |7 3 6 |2 4 1 
+4 3 2 |9 8 1 |6 7 5
+6 1 7 |4 2 5 |8 9 3
+5 9 8 |7 3 6 |2 4 1