module Chamomile::ANSI

# File lib/chamomile/styling/ansi.rb, line 34
def extract_escape(chars, start)
  return nil unless chars[start] == "\e"

  i = start + 1
  return nil if i >= chars.length

  if chars[i] == "["
    seq = +"\e["
    i += 1
    while i < chars.length && chars[i].match?(/[0-9;]/)
      seq << chars[i]
      i += 1
    end
    if i < chars.length && chars[i].match?(/[A-Za-z]/)
      seq << chars[i]
      return seq
    end
  end

  nil
end

# File lib/chamomile/styling/ansi.rb, line 22
def height(str)
  str.count("\n") + 1
end

# File lib/chamomile/styling/ansi.rb, line 13
def printable_width(str)
  stripped = strip(str)
  width = 0
  stripped.each_char do |ch|
    width += char_width(ch)
  end
  width
end

# File lib/chamomile/styling/ansi.rb, line 68
def sgr_open_after?(was_open, seq)
  return false if ["\e[0m", "\e[m"].include?(seq)
  return true if seq.match?(/\A\e\[\d/)

  was_open
end

# File lib/chamomile/styling/ansi.rb, line 26
def size(str)
  return [0, 1] if str.empty?

  lines = str.split("\n", -1)
  w = lines.map { |line| printable_width(line) }.max || 0
  [w, lines.length]
end

# File lib/chamomile/styling/ansi.rb, line 9
def strip(str)
  str.gsub(ESCAPE_RE, "")
end

# File lib/chamomile/styling/ansi.rb, line 56
def track_sgr(active_sgr, seq)
  if ["\e[0m", "\e[m"].include?(seq)
    active_sgr.clear
  elsif seq.match?(/\A\e\[\d/)
    if active_sgr.empty?
      active_sgr.replace(seq)
    else
      active_sgr.replace("#{active_sgr.delete_suffix("\e[0m")}#{seq}")
    end
  end
end