rucaptcha/lib/rucaptcha/captcha.rb

90 lines
3.1 KiB
Ruby

require 'posix-spawn'
module RuCaptcha
class Captcha
class << self
def random_color
if RuCaptcha.config.style == :colorful
color_seed = (rand(150) + 40).to_s(8)
color = [0.to_s(8), 0.to_s(8), 0.to_s(8)]
color[rand(3)] = color_seed
color
else
color_seed = rand(50).to_s(8)
[color_seed, color_seed, color_seed]
end
end
def random_chars
chars = SecureRandom.hex(RuCaptcha.config.len / 2).downcase
chars.gsub!(/[0ol1]/i, (rand(8) + 2).to_s)
chars
end
def rand_line_top(text_top, font_size)
text_top + rand(font_size * 0.7).to_i
end
# Create Captcha image by code
def create(code)
chars = code.split('')
all_left = 20
font_size = RuCaptcha.config.font_size
full_height = font_size
full_width = font_size * chars.size
size = "#{full_width}x#{full_height}"
half_width = full_width / 2
full_height = full_height
half_height = full_height / 2
text_top = 0
text_left = 0 - (font_size * 0.28).to_i
stroke_width = (font_size * 0.05).to_i + 1
text_width = font_size + text_left
label = "=#{' ' * (chars.size - 1)}="
text_opts = []
line_opts = []
chars.each_with_index do |char, i|
rgb = random_color
text_color = "rgba(#{rgb.join(',')}, 1)"
line_color = "rgba(#{rgb.join(',')}, 0.6)"
text_opts << %(-fill '#{text_color}' -draw 'text #{(text_left + text_width) * i + all_left},#{text_top} "#{char}"')
left_y = rand_line_top(text_top, font_size)
right_x = half_width + (half_width * 0.3).to_i
right_y = rand_line_top(text_top, font_size)
line_opts << %(-draw 'stroke #{line_color} line #{rand(10)},#{left_y} #{right_x},#{right_y}')
end
command = <<-CODE
convert -size #{size} \
-strokewidth #{stroke_width} \
#{line_opts.join(' ')} \
-pointsize #{font_size} -weight 500 \
#{text_opts.join(' ')} \
-wave #{rand(2) + 3}x#{rand(2) + 1} \
-rotate #{rand(10) - 5} \
-gravity NorthWest -sketch 1x10+#{rand(2)} \
-fill none \
-implode #{RuCaptcha.config.implode} -trim label:- png:-
CODE
if Gem.win_platform?
png_file_path = Rails.root.join('tmp', 'cache', "#{code}.png")
command = "convert -size #{size} xc:White -gravity Center -weight 12 -pointsize 20 -annotate 0 \"#{code}\" -trim #{png_file_path}"
require 'open3'
_stdout_str, stderr_str = Open3.capture3(command)
raise "RuCaptcha: #{stderr_str.strip}" if stderr_str != nil && stderr_str.length > 0
png_file_path
else
command.strip!
pid, stdin, stdout, stderr = POSIX::Spawn.popen4(command)
Process.waitpid(pid)
err = stderr.read
raise "RuCaptcha: #{err.strip}" if err != nil && err.length > 0
stdout.read
end
end
end
end
end