#encoding: UTF-8

#**************************************************************************************

# class IniFile

#**************************************************************************************

# This class represents the INI file and can be used to parse, modify,

# and write INI files.

class IniFile

  include Enumerable

  class Error < StandardError

  end

  VERSION = '3.0.0'

  # Public: Open an INI file and load the contents.

  #

  # filename - The name of the file as a String

  # opts     - The Hash of options (default: {})

  #            :comment   - String containing the comment character(s)

  #            :parameter - String used to separate parameter and value

  #            :encoding  - Encoding String for reading / writing

  #            :default   - The String name of the default global section

  #

  # Examples

  #

  #   IniFile.load('file.ini')

  #   #=> IniFile instance

  #

  #   IniFile.load('does/not/exist.ini')

  #   #=> nil

  #

  # Returns an IniFile instance or nil if the file could not be opened.

  def self.load(filename, opts = {})

    return unless File.file? filename

    new(opts.merge(:filename => filename))

  end

  # Get and set the filename

  attr_accessor :filename

  # Get and set the encoding

  attr_accessor :encoding

  # Public: Create a new INI file from the given set of options. If :content

  # is provided then it will be used to populate the INI file. If a :filename

  # is provided then the contents of the file will be parsed and stored in the

  # INI file. If neither the :content or :filename is provided then an empty

  # INI file is created.

  #

  # opts - The Hash of options (default: {})

  #   :content   - The String/Hash containing the INI contents

  #   :comment   - String containing the comment character(s)

  #   :parameter - String used to separate parameter and value

  #   :encoding  - Encoding String for reading / writing

  #   :default   - The String name of the default global section

  #   :filename  - The filename as a String

  #

  # Examples

  #

  #   IniFile.new

  #   #=> an empty IniFile instance

  #

  #   IniFile.new( :content => "[global]\nfoo=bar" )

  #   #=> an IniFile instance

  #

  #   IniFile.new( :filename => 'file.ini', :encoding => 'UTF-8' )

  #   #=> an IniFile instance

  #

  #   IniFile.new( :content => "[global]\nfoo=bar", :comment => '#' )

  #   #=> an IniFile instance

  #

  def initialize(opts = {})

    @comment = opts.fetch(:comment, ';#')

    @param = opts.fetch(:parameter, '=')

    @encoding = opts.fetch(:encoding, nil)

    @default = opts.fetch(:default, 'global')

    @filename = opts.fetch(:filename, nil)

    content = opts.fetch(:content, nil)

    @ini = Hash.new {|h, k| h[k] = Hash.new}

    case

      when content.is_a?(Hash)

        merge!(content)

      when content

        parse(content)

      when @filename

        read

      else

        merge!({})

    end

  end

  # Public: Write the contents of this IniFile to the file system. If left

  # unspecified, the currently configured filename and encoding will be used.

  # Otherwise the filename and encoding can be specified in the options hash.

  #

  # opts - The default options Hash

  #        :filename - The filename as a String

  #        :encoding - The encoding as a String

  #

  # Returns this IniFile instance.

  def write(opts = {})

    filename = opts.fetch(:filename, @filename)

    encoding = opts.fetch(:encoding, @encoding)

    mode = encoding ? "w:#{encoding}" : 'w'

    File.open(filename, mode) do |f|

      @ini.each do |section, hash|

        f.puts "[#{section}]"

        hash.each {|param, val| f.puts "#{param} #{@param} #{escape_value val}"}

        f.puts

      end

    end

    self

  end

  alias :save :write

  # Public: Read the contents of the INI file from the file system and replace

  # and set the state of this IniFile instance. If left unspecified the

  # currently configured filename and encoding will be used when reading from

  # the file system. Otherwise the filename and encoding can be specified in

  # the options hash.

  #

  # opts - The default options Hash

  #        :filename - The filename as a String

  #        :encoding - The encoding as a String

  #

  # Returns this IniFile instance if the read was successful; nil is returned

  # if the file could not be read.

  def read(opts = {})

    filename = opts.fetch(:filename, @filename)

    encoding = opts.fetch(:encoding, @encoding)

    return unless File.file? filename

    mode = encoding ? "r:#{encoding}" : 'r'

    File.open(filename, mode) {|fd| parse fd}

    self

  end

  alias :restore :read

  # Returns this IniFile converted to a String.

  def to_s

    s = []

    @ini.each do |section, hash|

      s << "[#{section}]"

      hash.each {|param, val| s << "#{param} #{@param} #{escape_value val}"}

      s << ''

    end

    s.join("\n")

  end

  # Returns this IniFile converted to a Hash.

  def to_h

    @ini.dup

  end

  # Public: Creates a copy of this inifile with the entries from the

  # other_inifile merged into the copy.

  #

  # other - The other IniFile.

  #

  # Returns a new IniFile.

  def merge(other)

    self.dup.merge!(other)

  end

  # Public: Merges other_inifile into this inifile, overwriting existing

  # entries. Useful for having a system inifile with user overridable settings

  # elsewhere.

  #

  # other - The other IniFile.

  #

  # Returns this IniFile.

  def merge!(other)

    return self if other.nil?

    my_keys = @ini.keys

    other_keys = case other

                   when IniFile

                     other.instance_variable_get(:@ini).keys

                   when Hash

                     other.keys

                   else

                     raise Error, "cannot merge contents from '#{other.class.name}'"

                 end

    (my_keys & other_keys).each do |key|

      case other[key]

        when Hash

          @ini[key].merge!(other[key])

        when nil

          nil

        else

          raise Error, "cannot merge section #{key.inspect} - unsupported type: #{other[key].class.name}"

      end

    end

    (other_keys - my_keys).each do |key|

      @ini[key] = case other[key]

                    when Hash

                      other[key].dup

                    when nil

                      {}

                    else

                      raise Error, "cannot merge section #{key.inspect} - unsupported type: #{other[key].class.name}"

                  end

    end

    self

  end

  # Public: Yield each INI file section, parameter, and value in turn to the

  # given block.

  #

  # block - The block that will be iterated by the each method. The block will

  #         be passed the current section and the parameter/value pair.

  #

  # Examples

  #

  #   inifile.each do |section, parameter, value|

  #     puts "#{parameter} = #{value} [in section - #{section}]"

  #   end

  #

  # Returns this IniFile.

  def each

    return unless block_given?

    @ini.each do |section, hash|

      hash.each {|param, val| yield section, param, val}

    end

    self

  end

  # Public: Yield each section in turn to the given block.

  #

  # block - The block that will be iterated by the each method. The block will

  #         be passed the current section as a Hash.

  #

  # Examples

  #

  #   inifile.each_section do |section|

  #     puts section.inspect

  #   end

  #

  # Returns this IniFile.

  def each_section

    return unless block_given?

    @ini.each_key {|section| yield section}

    self

  end

  # Public: Remove a section identified by name from the IniFile.

  #

  # section - The section name as a String.

  #

  # Returns the deleted section Hash.

  def delete_section(section)

    @ini.delete section.to_s

  end

  # Public: Get the section Hash by name. If the section does not exist, then

  # it will be created.

  #

  # section - The section name as a String.

  #

  # Examples

  #

  #   inifile['global']

  #   #=> global section Hash

  #

  # Returns the Hash of parameter/value pairs for this section.

  def [](section)

    return nil if section.nil?

    @ini[section.to_s]

  end

  # Public: Set the section to a hash of parameter/value pairs.

  #

  # section - The section name as a String.

  # value   - The Hash of parameter/value pairs.

  #

  # Examples

  #

  #   inifile['tenderloin'] = { 'gritty' => 'yes' }

  #   #=> { 'gritty' => 'yes' }

  #

  # Returns the value Hash.

  def []=(section, value)

    @ini[section.to_s] = value

  end

  # Public: Create a Hash containing only those INI file sections whose names

  # match the given regular expression.

  #

  # regex - The Regexp used to match section names.

  #

  # Examples

  #

  #   inifile.match(/^tree_/)

  #   #=> Hash of matching sections

  #

  # Return a Hash containing only those sections that match the given regular

  # expression.

  def match(regex)

    @ini.dup.delete_if {|section, _| section !~ regex}

  end

  # Public: Check to see if the IniFile contains the section.

  #

  # section - The section name as a String.

  #

  # Returns true if the section exists in the IniFile.

  def has_section?(section)

    @ini.has_key? section.to_s

  end

  # Returns an Array of section names contained in this IniFile.

  def sections

    @ini.keys

  end

  # Public: Freeze the state of this IniFile object. Any attempts to change

  # the object will raise an error.

  #

  # Returns this IniFile.

  def freeze

    super

    @ini.each_value {|h| h.freeze}

    @ini.freeze

    self

  end

  # Public: Mark this IniFile as tainted -- this will traverse each section

  # marking each as tainted.

  #

  # Returns this IniFile.

  def taint

    super

    @ini.each_value {|h| h.taint}

    @ini.taint

    self

  end

  # Public: Produces a duplicate of this IniFile. The duplicate is independent

  # of the original -- i.e. the duplicate can be modified without changing the

  # original. The tainted state of the original is copied to the duplicate.

  #

  # Returns a new IniFile.

  def dup

    other = super

    other.instance_variable_set(:@ini, Hash.new {|h, k| h[k] = Hash.new})

    @ini.each_pair {|s, h| other[s].merge! h}

    other.taint if self.tainted?

    other

  end

  # Public: Produces a duplicate of this IniFile. The duplicate is independent

  # of the original -- i.e. the duplicate can be modified without changing the

  # original. The tainted state and the frozen state of the original is copied

  # to the duplicate.

  #

  # Returns a new IniFile.

  def clone

    other = dup

    other.freeze if self.frozen?

    other

  end

  # Public: Compare this IniFile to some other IniFile. For two INI files to

  # be equivalent, they must have the same sections with the same parameter /

  # value pairs in each section.

  #

  # other - The other IniFile.

  #

  # Returns true if the INI files are equivalent and false if they differ.

  def eql?(other)

    return true if equal? other

    return false unless other.instance_of? self.class

    @ini == other.instance_variable_get(:@ini)

  end

  alias :== :eql?

  # Escape special characters.

  #

  # value - The String value to escape.

  #

  # Returns the escaped value.

  def escape_value(value)

    value = value.to_s.dup

    value.gsub!(/\\([0nrt])/, '\\\\\1')

    value.gsub!(/\n/, '\n')

    value.gsub!(/\r/, '\r')

    value.gsub!(/\t/, '\t')

    value.gsub!(/\0/, '\0')

    value

  end

  # Parse the given content and store the information in this IniFile

  # instance. All data will be cleared out and replaced with the information

  # read from the content.

  #

  # content - A String or a file descriptor (must respond to `each_line`)

  #

  # Returns this IniFile.

  def parse(content)

    parser = Parser.new(@ini, @param, @comment, @default)

    parser.parse(content)

    self

  end

end # IniFile

#**************************************************************************************

# class Parser

#**************************************************************************************

# The IniFile::Parser has the responsibility of reading the contents of an

# .ini file and storing that information into a ruby Hash. The object being

# parsed must respond to `each_line` - this includes Strings and any IO

# object.

class Parser

  attr_writer :section

  attr_accessor :property

  attr_accessor :value

  attr_accessor :section_regexp, :ignore_regexp, :property_regexp

  attr_accessor :open_quote, :close_quote

  attr_accessor :full_quote, :trailing_slash, :normal_value

  # Create a new IniFile::Parser that can be used to parse the contents of

  # an .ini file.

  #

  # hash    - The Hash where parsed information will be stored

  # param   - String used to separate parameter and value

  # comment - String containing the comment character(s)

  # default - The String name of the default global section

  #

  def initialize(hash, param, comment, default)

    @hash = hash

    @default = default

    comment = comment.to_s.empty? ? "\z" : "\\s*(?:[#{comment}].*)?\\z"

    self.section_regexp = /\A\s*\[([^\]]+)\]#{comment}/

    self.ignore_regexp = /\A#{comment}/

    self.property_regexp = /\A(.*?)(?<!\\)#{param}(.*)\z/

    self.open_quote = /\A\s*(".*)\z/

    self.close_quote = /\A(.*(?<!\\)")#{comment}/

    self.full_quote = /\A\s*(".*(?<!\\)"[^<!\\]*)#{comment}/

    self.trailing_slash = /\A(.*)(?<!\\)\\#{comment}/

    self.normal_value = /\A(.*?)#{comment}/

  end

  # Returns `true` if the current value starts with a leading double quote.

  # Otherwise returns false.

  def leading_quote?

    value && value =~ /\A"/

  end

  # Given a string, attempt to parse out a value from that string. This

  # value might be continued on the following line. So this method returns

  # `true` if it is expecting more data.

  #

  # string - String to parse

  #

  # Returns `true` if the next line is also part of the current value.

  # Returns `false` if the string contained a complete value.

  def parse_value(string)

    continuation = false

    # if our value starts with a double quote, then we are in a

    # line continuation situation

    if leading_quote?

      # check for a closing quote at the end of the string

      if string =~ self.close_quote

        value << $1

        # otherwise just append the string to the value

      else

        value << string

        continuation = true

      end

      # not currently processing a continuation line

    else

      case string

        when self.full_quote

          self.value = $1

        when self.open_quote

          self.value = $1

          continuation = true

        when self.trailing_slash

          self.value ? self.value << $1 : self.value = $1

          continuation = true

        when self.normal_value

          self.value ? self.value << $1 : self.value = $1

        else

          error

      end

    end

    if continuation

      self.value << $/ if leading_quote?

    else

      process_property

    end