class Bundler::Dsl::DSLError

def contents
  @contents ||= dsl_path && File.exist?(dsl_path) && File.read(dsl_path)
end

def initialize(description, dsl_path, backtrace, contents = nil)
  @status_code = $!.respond_to?(:status_code) && $!.status_code
  @description = description
  @dsl_path    = dsl_path
  @backtrace   = backtrace
  @contents    = contents
end

def parse_line_number_from_description
  description = self.description
  if dsl_path && description =~ /((#{Regexp.quote File.expand_path(dsl_path)}|#{Regexp.quote dsl_path}):\d+)/
    trace_line = Regexp.last_match[1]
    description = description.sub(/\n.*\n(\.\.\.)? *\^~+$/, "").sub(/#{Regexp.quote trace_line}:\s*/, "").sub("\n", " - ")
  end
  [trace_line, description]
end

def status_code
  @status_code || super
end

def to_s
  @to_s ||= begin
    trace_line, description = parse_line_number_from_description
    m = String.new("\n[!] ")
    m << description
    m << ". Bundler cannot continue.\n"
    return m unless backtrace && dsl_path && contents
    trace_line = backtrace.find {|l| l.include?(dsl_path) } || trace_line
    return m unless trace_line
    line_number = trace_line.split(":")[1].to_i - 1
    return m unless line_number
    lines      = contents.lines.to_a
    indent     = " #  "
    indicator  = indent.tr("#", ">")
    first_line = line_number.zero?
    last_line  = (line_number == (lines.count - 1))
    m << "\n"
    m << "#{indent}from #{trace_line.gsub(/:in.*$/, "")}\n"
    m << "#{indent}-------------------------------------------\n"
    m << "#{indent}#{lines[line_number - 1]}" unless first_line
    m << "#{indicator}#{lines[line_number]}"
    m << "#{indent}#{lines[line_number + 1]}" unless last_line
    m << "\n" unless m.end_with?("\n")
    m << "#{indent}-------------------------------------------\n"
  end
end