module ICU
  #
  # A player in a tournament must have a first name, a last name and a number
  # which is unique in the tournament but otherwise arbitary.
  #
  #   bobby = ICU::Player.new(' robert  j ', 'fischer', 17)
  #
  # Names are automatically cannonicalised (tidied up).
  #
  #   bobby.first_name                 # => 'Robert J.'
  #   bobby.last_name                  # => 'Fischer'
  #
  # But the original untidied (other than white space cleanup and the addition of a comma
  # to separate last name from first name) is avaiable from the _original_name_ method:
  #
  #   bobby.original_name              # => "fischer, robert j"
  #
  # This original name, set via the constructor, is unchanged by subsequent calls to
  # the setter methods _first_name_ or _last_name.
  #
  #   booby.first_name = 'Robert James'
  #   bobby.original_name              # => "fischer, robert j"
  #
  #  You can reset _orignal_name_, if necessary, and this does not affect either _first_name_ or _last_name_.
  #
  #   bobby.original_name = "Fischer, Robert James"
  #
  # In addition, players have a number of optional attributes which can be specified
  # via setters or in constructor hash options: _id_ (local or national ID), _fide_
  # (FIDE ID), _fed_ (federation), _title_, _rating_ (local rating), _fide_rating,
  # _rank_ and _dob_ (date of birth).
  #
  #   peter = ICU::Player.new('Peter', 'Svidler', 21, :fed => 'rus', :title => 'g', :fide_rating = 2700)
  #   peter.dob = '17th June, 1976'
  #   peter.rank = 1
  #
  # Some of these values will also be canonicalised to some extent. For example,
  # date of birth will be turned into _yyyy-mm-dd_ format, the chess title will be two
  # to three capital letters always ending in _M_ and the federation, if it's three
  # letters long, will be upcased.
  #
  #   peter.dob                        # => 1976-07-17
  #   peter.title                      # => 'GM'
  #   peter.fed                        # => 'RUS'
  #
  # It is preferable to add results (ICU::Result) to a player via the tournament (ICU::Tournament) object's
  # _add_result_ method rather than the method of the same name belonging to player instances. Doing so
  # allows mirrored results to be added to both players with one call (e.g. one player won, so the
  # other lost). A player's results can later be retieved via the _results_ accessor.
  #
  # Total scores is available via the _points_ method.
  #
  #   peter.points                     # => 5.5
  #
  # A player can have up to two ID numbers (both positive integers or nil): _id_ (local or national ID,
  # such as ICU number) and _fide_ (FIDE ID).
  #
  #   peter.id = 16790                 # ICU
  #   peter.fide = 4102142             # FIDE
  #
  # Players can be compared to see if they're roughly or exactly the same, which may be useful in detecting duplicates.
  # If the names match and the federations don't disagree then two players are equal according to the _==_ operator.
  # The player number is irrelevant.
  #
  #   john1 = ICU::Player.new('John', 'Smith', 12)
  #   john2 = ICU::Player.new('John', 'Smith', 22, :fed = 'IRL')
  #   john2 = ICU::Player.new('John', 'Smith', 32, :fed = 'ENG')
  #
  #   john1 == john2                   # => true (federations don't disagree because one is unset)
  #   john2 == john3                   # => false (federations disagree)
  #
  # If, in addition, _rating_, _dob_, _gender_, _id_ and _fide_ do not disagree then two players are equal
  # according to the stricter criteria of _eql?_.
  #
  #   mark1 = ICU::Player.new('Mark', 'Orr', 31, :fed = 'IRL', :rating => 2100)
  #   mark2 = ICU::Player.new('Mark', 'Orr', 33, :fed = 'IRL', :rating => 2100, :title => 'IM')
  #   mark3 = ICU::Player.new('Mark', 'Orr', 37, :fed = 'IRL', :rating => 2200, :title => 'IM')
  #
  #   mark1.eql?(mark2)                # => true (ratings agree and titles don't disagree)
  #   mark2.eql?(mark3)                # => false (the ratings are not the same)
  #
  # The presence of two players in the same tournament that are equal according to _==_ but unequal
  # according to _eql?__ is likely to indicate a data entry error.
  #
  # If two instances represent the same player and are equal according to _==_ then the _id_, _fide_, _rating_,
  # _title_ and _fed_ attributes of the two can be merged. For example:
  #
  #   fox1 = ICU::Player.new('Tony', 'Fox', 12, :id => 456)
  #   fox2 = ICU::Player.new('Tony', 'Fox', 21, :rating => 2100, :fed => 'IRL', :gender => 'M')
  #   fox1.merge(fox2)
  #
  # Any attributes present in the second player but not in the first are copied to the first.
  # All other attributes are unaffected.
  #
  #   fox1.rating                      # => 2100
  #   fox1.fed                         # => 'IRL'
  #   fox1.gender                      # => 'M'
  #
  class Player
    extend ICU::Util::Accessor
    attr_integer :num
    attr_positive_or_nil :id, :fide_id, :rating, :fide_rating, :rank
    attr_date_or_nil :dob

    attr_reader :results, :first_name, :last_name, :original_name, :fed, :title, :gender

    # Constructor. Must supply both names and a unique number for the tournament.
    def initialize(first_name, last_name, num, opt={})
      self.first_name = first_name
      self.last_name  = last_name
      @original_name  = Name.new(first_name, last_name).original
      self.num        = num
      [:id, :fide_id, :fed, :title, :rating, :fide_rating, :rank, :dob, :gender].each do |atr|
        self.send("#{atr}=", opt[atr]) unless opt[atr].nil?
      end
      @results = []
    end

    # Canonicalise and set the first name(s).
    def first_name=(first_name)
      name = Name.new(first_name, 'Last')
      @first_name = name.first
    end

    # Canonicalise and set the last name(s).
    def last_name=(last_name)
      name = Name.new('First', last_name)
      raise "invalid last name" unless name.last.length > 0 && name.first.length > 0
      @last_name = name.last
    end

    # Reset the original name.
    def original_name=(original_name)
      @original_name = ICU::Util::String.to_utf8(original_name)
    end

    # Return the full name, last name first.
    def name
      "#{last_name}, #{first_name}"
    end

    # Federation. Is either unknown (nil) or a string containing at least three letters.
    def fed=(fed)
      obj = ICU::Federation.find(fed)
      @fed = obj ? obj.code : nil
      raise "invalid federation (#{fed})" if @fed.nil? && fed.to_s.strip.length > 0
    end

    # Chess title. Is either unknown (nil) or one of: _GM_, _IM_, _FM_, _CM_, _NM_,
    # or any of these preceeded by the letter _W_.
    def title=(title)
      @title = title.to_s.strip.upcase
      @title << 'M' if @title.match(/[A-LN-Z]$/)
      @title = 'IM' if @title == 'M'
      @title = 'WIM' if @title == 'WM'
      @title = '' if @title.match(/^(AFM|AIM|AGM)$/)
      @title = nil if @title == ''
      raise "invalid chess title (#{title})" unless @title.nil? || @title.match(/^W?[GIFCN]M$/)
    end

    # Gender. Is either unknown (nil) or one of _M_ or _F_.
    def gender=(gender)
      @gender = gender.to_s.strip[0,1].upcase
      @gender = nil if @gender == ''
      @gender = 'F' if @gender == 'W'
      raise "invalid gender (#{gender})" unless @gender.nil? || @gender.match(/^[MF]$/)
    end

    # Add a result. Don't use this method directly - use ICU::Tournament#add_result instead.
    def add_result(result)
      raise "invalid result" unless result.class == ICU::Result
      raise "player number (#{@num}) is not matched to result player number (#{result.inspect})" unless @num == result.player
      already = @results.find_all { |r| r.round == result.round }
      return if already.size == 1 && already[0].eql?(result)
      raise "player #{@num} already has a result in round #{result.round} (#{already[0].inspect}) which does not match the one being added (#{result.inspect})" unless already.size == 0
      if @results.size == 0 || @results.last.round <= result.round
        @results << result
      else
        i = (0..@results.size-1).find { |n| @results[n].round > result.round }
        @results.insert(i, result)
      end
    end

    # Lookup a result by round number and return it (or nil if there is no such result).
    def find_result(round)
      @results.find { |r| r.round == round }
    end

    # Lookup a result by round number, remove it and return it (or return nil if there is no such result).
    def remove_result(round)
      result = find_result(round)
      return unless result
      @results.delete(result)
      result
    end

    # Return the player's total points.
    def points
      @results.inject(0.0) { |t, r| t += r.points }
    end

    # Renumber the player according to the supplied hash. Return self.
    def renumber(map)
      raise "player number #{@num} not found in renumbering hash" unless map[@num]
      self.num = map[@num]
      @results.each{ |r| r.renumber(map) }
      self
    end

    # Loose equality test. Passes if the names match and the federations are not different.
    def ==(other)
      return true if equal?(other)
      return false unless other.is_a? Player
      return false unless @first_name == other.first_name
      return false unless @last_name  == other.last_name
      return false if @fed && other.fed && @fed != other.fed
      true
    end

    # Strict equality test. Passes if the playes are loosly equal and also if their IDs, rating, gender and title are not different.
    def eql?(other)
      return true if equal?(other)
      return false unless self == other
      [:id, :fide_id, :rating, :fide_rating, :title, :gender].each do |m|
        return false if self.send(m) && other.send(m) && self.send(m) != other.send(m)
      end
      true
    end

    # Merge in some of the details of another player.
    def merge(other)
      raise "cannot merge two players that are not equal" unless self == other
      [:id, :fide_id, :rating, :fide_rating, :title, :fed, :gender].each do |m|
        self.send("#{m}=", other.send(m)) unless self.send(m)
      end
    end
  end
end