#
# Shoes Minesweeper by que/varyform
#
LEVELS = { :beginner => [9, 9, 10], :intermediate => [16, 16, 40], :expert => [30, 16, 99] }
COLORS = %w(#00A #0A0 #A00 #004 #040 #400 #000)

class Field
  CELL_SIZE = 20
  
  class Cell
    attr_accessor :flag
    def initialize(aflag = false)
      @flag = aflag
    end
  end
  
  class Bomb < Cell
    attr_accessor :exploded
    def initialize(exploded = false)
      @exploded = exploded
    end
  end
  
  class OpenCell < Cell
    attr_accessor :number
    def initialize(bombs_around = 0)
      @number = bombs_around
    end
  end
  
  class EmptyCell < Cell; end
  
  attr_reader :cell_size, :offset
  
  def initialize(app, level = :beginner)
    @app = app
    @field = []
    @w, @h, @bombs = LEVELS[level][0], LEVELS[level][1], LEVELS[level][2]
    @h.times { @field << Array.new(@w) { EmptyCell.new } }
    @game_over = false
    @width, @height, @cell_size = @w * CELL_SIZE, @h * CELL_SIZE, CELL_SIZE
    @offset = [(@app.width - @width.to_i) / 2, (@app.height - @height.to_i) / 2]
    plant_bombs
    @start_time = Time.now
  end
  
  def total_time
    @latest_time = Time.now - @start_time unless game_over? || all_found?
    @latest_time
  end
  
  def click!(x, y)
    return unless cell_exists?(x, y)
    return if has_flag?(x, y)
    return die!(x, y) if bomb?(x, y)
    open(x, y)
    discover(x, y) if bombs_around(x, y) == 0
  end  

  def flag!(x, y)
    return unless cell_exists?(x, y)
    self[x, y].flag = !self[x, y].flag unless self[x, y].is_a?(OpenCell)
  end  
  
  def game_over?
    @game_over 
  end
  
  def render_cell(x, y, color = "#AAA", stroke = true)
    @app.stroke "#666" if stroke
    @app.fill color
    @app.rect x*cell_size, y*cell_size, cell_size-1, cell_size-1
    @app.stroke "#BBB" if stroke
    @app.line x*cell_size+1, y*cell_size+1, x*cell_size+cell_size-1, y*cell_size
    @app.line x*cell_size+1, y*cell_size+1, x*cell_size, y*cell_size+cell_size-1
  end
  
  def render_flag(x, y)
    @app.stroke "#000"
    @app.line(x*cell_size+cell_size / 4 + 1, y*cell_size + cell_size / 5, x*cell_size+cell_size / 4 + 1, y*cell_size+cell_size / 5 * 4)
    @app.fill "#A00"
    @app.rect(x*cell_size+cell_size / 4+2, y*cell_size + cell_size / 5, 
      cell_size / 3, cell_size / 4)
  end
  
  def render_bomb(x, y)
    render_cell(x, y)
    if (game_over? or all_found?) then # draw bomb
      if self[x, y].exploded then
        render_cell(x, y, @app.rgb(0xFF, 0, 0, 0.5))
      end
      @app.nostroke
      @app.fill @app.rgb(0, 0, 0, 0.8)
      @app.oval(x*cell_size+3, y*cell_size+3, 13)
      @app.fill "#333"
      @app.oval(x*cell_size+5, y*cell_size+5, 7)
      @app.fill "#AAA"
      @app.oval(x*cell_size+6, y*cell_size+6, 3)
      @app.fill @app.rgb(0, 0, 0, 0.8)
      @app.stroke "#222"
      @app.strokewidth 2
      @app.oval(x*cell_size + cell_size / 2 + 2, y*cell_size + cell_size / 4 - 2, 2)
      @app.oval(x*cell_size + cell_size / 2 + 4, y*cell_size + cell_size / 4 - 2, 1)
      @app.strokewidth 1
    end
  end
  
  def render_number(x, y)
    render_cell(x, y, "#999", false)
    if self[x, y].number != 0 then
      @app.nostroke
      @app.para self[x, y].number.to_s, :left => x*cell_size + 3 + offset.first, :top => y*cell_size + offset.last - 2, 
        :font => '13px', :stroke => COLORS[self[x, y].number - 1]
    end
  end
  
  def paint
    0.upto @h-1 do |y|
      0.upto @w-1 do |x|
        @app.nostroke
        case self[x, y]
          when EmptyCell then render_cell(x, y)
          when Bomb then render_bomb(x, y)
          when OpenCell then render_number(x, y)
        end
        render_flag(x, y) if has_flag?(x, y) && !(game_over? && bomb?(x, y))
      end
    end
  end  

  def bombs_left
    @bombs - @field.flatten.compact.reject {|e| !e.flag }.size
  end  

  def all_found?
    @field.flatten.compact.reject {|e| !e.is_a?(OpenCell) }.size + @bombs == @w*@h
  end  

  def reveal!(x, y)
    return unless cell_exists?(x, y)
    return unless self[x, y].is_a?(Field::OpenCell)
    if flags_around(x, y) >= self[x, y].number then
      (-1..1).each do |v|
        (-1..1).each { |h| click!(x+h, y+v) unless (v==0 && h==0) or has_flag?(x+h, y+v) }
      end
    end      
  end  
  
  private 
  
  def cell_exists?(x, y)
    ((0...@w).include? x) && ((0...@h).include? y)
  end
  
  def has_flag?(x, y)
    return false unless cell_exists?(x, y)
    return self[x, y].flag
  end
  
  def bomb?(x, y)
    cell_exists?(x, y) && (self[x, y].is_a? Bomb)
  end
  
  def can_be_discovered?(x, y)
    return false unless cell_exists?(x, y)
    return false if self[x, y].flag
    cell_exists?(x, y) && (self[x, y].is_a? EmptyCell) && !bomb?(x, y) && (bombs_around(x, y) == 0)
  end  
  
  def open(x, y)
    self[x, y] = OpenCell.new(bombs_around(x, y)) unless (self[x, y].is_a? OpenCell) or has_flag?(x, y)
  end
  
  def neighbors
    (-1..1).each do |col|
      (-1..1).each { |row| yield row, col unless col==0 && row == 0 }
    end  
  end
  
  def discover(x, y)
    open(x, y)
    neighbors do |col, row|
      cx, cy = x+row, y+col
      next unless cell_exists?(cx, cy)
      discover(cx, cy) if can_be_discovered?(cx, cy)
      open(cx, cy)
    end
  end  

  def count_neighbors
    return 0 unless block_given?
    count = 0
    neighbors { |h, v| count += 1 if yield(h, v) }
    count
  end
  
  def bombs_around(x, y)
    count_neighbors { |v, h| bomb?(x+h, y+v) }
  end
  
  def flags_around(x, y)
    count_neighbors { |v, h| has_flag?(x+h, y+v) }
  end
  
  def die!(x, y)
    self[x, y].exploded = true
    @game_over = true
  end

  def plant_bomb(x, y)
    self[x, y].is_a?(EmptyCell) ? self[x, y] = Bomb.new : false
  end
  
  def plant_bombs
    @bombs.times { redo unless plant_bomb(rand(@w), rand(@h)) }
  end

  def [](*args)
    x, y = args
    raise "Cell #{x}:#{y} does not exists!" unless cell_exists?(x, y)
    @field[y][x]
  end
  
  def []=(*args)
    x, y, v = args
    cell_exists?(x, y) ? @field[y][x] = v : false
  end
end

Shoes.app :width => 730, :height => 450, :title => 'Minesweeper' do
  def render_field
    clear do
      background rgb(50, 50, 90, 0.7)
      flow :margin => 4 do
        button("Beginner") { new_game :beginner }
        button("Intermediate") {new_game :intermediate }
        button("Expert") { new_game :expert }
      end
      stack do @status = para :stroke => white end
      @field.paint
      para "Left click - open cell, right click - put flag, middle click - reveal empty cells", :top => 420, :left => 0, :stroke => white,  :font => "11px"
    end  
  end
  
  def new_game level
    @field = Field.new self, level
    translate -@old_offset.first, -@old_offset.last unless @old_offset.nil?
    translate @field.offset.first, @field.offset.last
    @old_offset = @field.offset
    render_field
  end
  
  new_game :beginner
  animate(5) { @status.replace "Time: #{@field.total_time.to_i} Bombs left: #{@field.bombs_left}" }
  
  click do |button, x, y|
    next if @field.game_over? || @field.all_found?
    fx, fy = ((x-@field.offset.first) / @field.cell_size).to_i, ((y-@field.offset.last) / @field.cell_size).to_i
    @field.click!(fx, fy) if button == 1
    @field.flag!(fx, fy) if button == 2
    @field.reveal!(fx, fy) if button == 3

    render_field
    alert("Winner!\nTotal time: #{@field.total_time}") if @field.all_found?
    alert("Bang!\nYou loose.") if @field.game_over?
  end
end