require 'logger'
require 'rubygems'
require 'tailor/spacing'
require 'tailor/indentation'
require 'term/ansicolor'

module Tailor

  # Calling modules will get the Ruby file to check, then read by line.  This
  # class allows for checking of line-specific style by Represents a single
  # line of a file of Ruby code.  Inherits from String so "self" can be used.
  #
  # Methods are named such that they check for bad style conditions, and return
  # true and print the associated error message when the bad style condition
  # is discovered in the file line.
  class FileLine < String
    include Tailor::Spacing
    include Tailor::Indentation
    include Term::ANSIColor

    LINE_LENGTH_MAX = 80

    # This passes the line of code to String (the parent) so that it can act
    # like a standard string.
    #
    # @param [String] line_of_code Line from a Ruby file that will be checked
    #   for styling.
    # @param [Pathname] file_path Path to the file the line is in.
    # @param [Number] line_number Line number in the file that contains the
    #   line.
    # @return [String] Returns a String that includes all of the methods
    #   defined here.
    def initialize(line_of_code, file_path, line_number)
      super line_of_code
      @file_path = file_path
      @line_number = line_number
      @line_problem_count = 0
      @logger = ::Logger.new(STDOUT)
      #@logger.datetime_format = "%H:%M:%S"
      @logger.datetime_format = ""
    end

    # Checks to see if the method name is using camel case.
    #
    # @return [Boolean] Returns true if the method name is camel case.
    #   Returns nil if this line doesn't contain a method definition.
    def camel_case_method?
      words = self.split(/ /)

      # If we're not dealing with a method, get outta here.
      unless self.method_line?
        return nil
      end

      # The 2nd word is the method name, so evaluate that for caps chars.
      if words[1] =~ /[A-Z]/
        @line_problem_count += 1
        print_problem "Method name uses camel case"
        return true
      end

      false
    end

    # Checks to see if the class name is using snake case.
    #
    # @return [Boolean] Returns true if the class name is snake case.
    #   Returns nil if this line doesn't contain a class definition.
    def snake_case_class?
      words = self.split(/ /)

      # If we're dealing with a class, check for an underscore.
      unless self.class_line?
        return nil
      end

      # The 2nd word is the class name, so check that.
      if words[1] =~ /_/
        @line_problem_count += 1
        print_problem "Class name does NOT use camel case"
        return true
      end

      false
    end

    # Checks to see if the line is the start of a method's definition.
    #
    # @return [Boolean] Returns true if the line starts with 'def'.
    def method_line?
      words = self.strip.split(/ /)
      if words[0].eql? "def"
        return true
      end

      false
    end

    # Returns the name of the method if the line is one that contains a method
    # definition.
    #
    # @return [String] The method name.
    def method_name
      unless self.method_line?
        return nil
      end

      words = self.strip.split(/ /)
      words[1]
    end

    # Checks to see if the line is the start of a class's definition.
    #
    # @return [Boolean] Returns true if the line contains 'class' and the
    #   second word begins with a uppercase letter.
    def class_line?
      words = self.split(/ /)
      if words[0].eql? "class" and starts_with_uppercase?(words[1])
        return true
      end

      false
    end

    # Checks to see if the line is a regular statement (not a class, method, or
    # comment).
    #
    # @return [Boolean] Returns true if the line is not a class, method or
    #   comment.
    def statement_line?
      if self.method_line? or self.class_line? or self.comment_line?
        return false
      end

      true
    end

    # Checks to see if the whole line is a basic comment line.  This doesn't
    # check for trailing-line comments (@see #trailing_comment?).
    #
    # @return [Boolean] Returns true if the line begins with a pound symbol.
    def comment_line?
      unless self.scan(/^\s*#/).empty?
        return true
      end

      false
    end

    # Checks to see if the whole line is only space characters.
    #
    # @return [Boolean] Returns true if the line is only space characters.
    def empty_line?
      if self.scan(/^\s*$/).empty?
        return false
      end

      true
    end

    # Checks to see if the line is greater than the defined max (80 chars is
    # default).
    #
    # @return [Boolean] Returns true if the line length exceeds the allowed
    #   length.
    def too_long?
      length = self.length
      if length > LINE_LENGTH_MAX
        @line_problem_count += 1
        print_problem "Line is >#{LINE_LENGTH_MAX} characters (#{length})"
        return true
      end

      false
    end

    #-----------------------------------------------------------------
    # Private methods
    #-----------------------------------------------------------------
    private

    # Prints the file name and line number that the problem occurred on.
    #
    # @param [String] Error message to print.
    def print_problem message
      if @line_problem_count == 1
        line_info = "Problems in"
        line_info += " #{@file_path.relative_path_from(Pathname.pwd)}"
        line_info += " [#{@line_number}]:"

        puts ""
        puts line_info
      end

      puts red("\t"+ message)
    end

    # Checks to see if a word begins with a lowercase letter.
    #
    # @param [String] word The word to check case on.
    def starts_with_lowercase? word
      if word =~ /^[a-z]/
        return true
      end

      false
    end

    # Checks to see if a word begins with an uppercase letter.
    #
    # @param [String] word The word to check case on.
    def starts_with_uppercase? word
      if word =~ /^[A-Z]/
        return true
      end

      false
    end
  end
end