module Vedeu
# Provides the mechanism to decorate an interface with a border on all edges,
# or specific edges. The characters which are used for the border parts (e.g.
# the corners, verticals and horizontals) can be customised as can the colours
# and styles.
#
# @note Refer to UTF-8 U+2500 to U+257F for border characters. More details
# can be found at: http://en.wikipedia.org/wiki/Box-drawing_character
#
# @api private
class Border
extend Forwardable
include Vedeu::Common
include Vedeu::Model
include Vedeu::Presentation
def_delegators :geometry,
:x,
:xn,
:y,
:yn
def_delegators :interface, :visible?
# @!attribute [rw] attributes
# @return [Hash]
attr_accessor :attributes
# @!attribute [rw] bottom_left
# @return [String]
attr_accessor :bottom_left
# @!attribute [rw] bottom_right
# @return [String]
attr_accessor :bottom_right
# @!attribute [rw] horizontal
# @return [String]
attr_accessor :horizontal
# @!attribute [rw] show_bottom
# @return [Boolean]
attr_accessor :show_bottom
alias_method :bottom?, :show_bottom
# @!attribute [rw] show_left
# @return [Boolean]
attr_accessor :show_left
alias_method :left?, :show_left
# @!attribute [rw] show_right
# @return [Boolean]
attr_accessor :show_right
alias_method :right?, :show_right
# @!attribute [rw] show_top
# @return [Boolean]
attr_accessor :show_top
alias_method :top?, :show_top
# @!attribute [rw] title
# @return [String]
attr_accessor :title
# @!attribute [rw] top_left
# @return [String]
attr_accessor :top_left
# @!attribute [rw] top_right
# @return [String]
attr_accessor :top_right
# @!attribute [rw] vertical
# @return [String]
attr_accessor :vertical
# @!attribute [r] name
# @return [String]
attr_reader :name
# @!attribute [r] enabled
# @return [Boolean]
attr_reader :enabled
alias_method :enabled?, :enabled
# Returns a new instance of Vedeu::Border.
#
# @param attributes [Hash]
# @option attributes bottom_left [String] The bottom left border character.
# @option attributes bottom_right [String] The bottom right border
# character.
# @option attributes colour [Hash]
# @option attributes enabled [Boolean] Indicate whether the border is to be
# shown for this interface.
# @option attributes horizontal [String] The horizontal border character.
# @option attributes name [String] The name of the interface to which this
# border relates.
# @option attributes style []
# @option attributes show_bottom [Boolean] Indicate whether the bottom
# border is to be shown.
# @option attributes show_left [Boolean] Indicate whether the left border
# is to be shown.
# @option attributes show_right [Boolean] Indicate whether the right border
# is to be shown.
# @option attributes show_top [Boolean] Indicate whether the top border is
# to be shown.
# @option attributes title [String] A title bar for when the top border is
# to be shown.
# @option attributes top_left [String] The top left border character.
# @option attributes top_right [String] The top right border character.
# @option attributes vertical [String] The vertical border character.
# @return [Border]
def initialize(attributes = {})
@attributes = defaults.merge!(attributes)
@attributes.each do |key, value|
instance_variable_set("@#{key}", value)
end
end
# @return [Fixnum]
def bx
@bx ||= (enabled? && left?) ? x + 1 : x
end
# @return [Fixnum]
def bxn
@bxn ||= (enabled? && right?) ? xn - 1 : xn
end
# @return [Fixnum]
def by
@by ||= (enabled? && top?) ? y + 1 : y
end
# @return [Fixnum]
def byn
@byn ||= (enabled? && bottom?) ? yn - 1 : yn
end
# Returns the width of the interface determined by whether a left, right,
# both or neither borders are shown.
#
# @return [Fixnum]
def width
(bx..bxn).size
end
# Returns the height of the interface determined by whether a top, bottom,
# both or neither borders are shown.
#
# @return [Fixnum]
def height
(by..byn).size
end
# @return [Array<Array<Vedeu::Char>>]
def render
return [] unless visible?
return [] unless enabled?
Vedeu.timer("Rendering border: #{name}") do
out = [top, bottom]
height.times do |y|
out << [left(y), right(y)]
end
out.flatten
end
end
# @return [String]
def to_s
Vedeu::Renderers::Text.render(render)
end
alias_method :to_str, :to_s
# Renders the bottom border for the interface.
#
# @return [String]
def bottom
return [] unless bottom?
out = []
out << border(bottom_left, :bottom_left, *[yn, x]) if left?
out << horizontal_border(:bottom_horizontal, yn)
out << border(bottom_right, :bottom_right, *[yn, xn]) if right?
out
end
# Renders the left border for the interface.
#
# @param iy [Fixnum]
# @return [String]
def left(iy = 0)
return [] unless left?
border(vertical, :left_vertical, *[(by + iy), x])
end
# Renders the right border for the interface.
#
# @param iy [Fixnum]
# @return [String]
def right(iy = 0)
return [] unless right?
border(vertical, :left_vertical, *[(by + iy), xn])
end
# Renders the top border for the interface.
#
# @return [String]
def top
return [] unless top?
out = []
out << border(top_left, :top_left, *[y, x]) if left?
if title?
out << titlebar
else
out << horizontal_border(:top_horizontal, y)
end
out << border(top_right, :top_right, *[y, xn]) if right?
out
end
# The parent of a border is always an interface.
#
# @return [Vedeu::Interface]
def parent
interface
end
private
# @param position [Symbol] Either :top_horizontal, or :bottom_horizontal.
# @return [Array<Vedeu::Char>]
def horizontal_border(position, y_coordinate)
width.times.each_with_object([]) do |ix, a|
a << border(horizontal, position, *[y_coordinate, (bx + ix)])
end
end
# From the second element of {#title_characters} remove the border from each
# {#horizontal_border} Vedeu::Char, and add the title character.
#
# @return [Array<Vedeu::Char>]
def titlebar
horizontal_border(:top_horizontal, y).each_with_index do |char, index|
if index >= 1 && index <= title_characters.size
char.border = nil
char.value = title_characters[(index - 1)]
end
end
end
# @return [Array<String>]
def title_characters
@title_characters ||= padded_title.chars
end
# Pads the title with a single whitespace either side.
#
# @example
# title = 'Truncated!'
# width = 20
# # => ' Truncated! '
#
# width = 10
# # => ' Trunca '
#
# @return [String]
# @see #truncated_title
def padded_title
truncated_title.center(truncated_title.size + 2)
end
# Truncates the title to the width of the interface, minus characters needed
# to ensure there is at least a single character of horizontal border and a
# whitespace on either side of the title.
#
# @example
# title = 'Truncated!'
# width = 20
# # => 'Truncated!'
#
# width = 10
# # => 'Trunca'
#
# @return [String]
def truncated_title
title.chomp.slice(0..(width - 5))
end
# Return boolean indicating whether this border has a non-empty title.
#
# @return [Boolean]
def title?
present?(title)
end
# @param value [String]
# @param type [Symbol|NilClass]
# @param iy [Fixnum]
# @param ix [Fixnum]
# @return [Vedeu::Char]
def border(value, type = :border, iy = 0, ix = 0)
Vedeu::Char.new(value: value,
parent: interface,
colour: colour,
style: style,
position: Vedeu::Position[iy, ix],
border: type)
end
# @return [Vedeu::Geometry]
def geometry
Vedeu.geometries.by_name(name)
end
# @return [Vedeu::Interface]
def interface
@interface ||= Vedeu.interfaces.find(name)
end
# The default values for a new instance of this class.
#
# @note
# Using the '\uXXXX' variant produces gaps in the border, whilst the
# '\xXX' renders 'nicely'.
#
# @return [Hash]
def defaults
{
bottom_left: "\x6D", # └ # \u2514
bottom_right: "\x6A", # ┘ # \u2518
client: nil,
colour: nil,
enabled: false,
horizontal: "\x71", # ─ # \u2500
name: '',
repository: Vedeu.borders,
show_bottom: true,
show_left: true,
show_right: true,
show_top: true,
style: nil,
title: '',
top_left: "\x6C", # ┌ # \u250C
top_right: "\x6B", # ┐ # \u2510
vertical: "\x78", # │ # \u2502
}
end
end # Border
end # Vedeu