class Metanorma::Utils::Log

def add(category, loc, msg)
  return if @novalid
  @log[category] = [] unless @log[category]
  @log[category] << { location: current_location(loc), message: msg,
                      context: context(loc) }
  loc = loc.nil? ? "" : "(#{current_location(loc)}): "
  warn "#{category}: #{loc}#{msg}" 
end

def context(n)
  return nil if n.is_a? String
  n.respond_to?(:to_xml) and return n.to_xml
  n.respond_to?(:to_s) and return n.to_s
  nil
end

def current_location(n)
  return "" if n.nil?
  return n if n.is_a? String
  return "Asciidoctor Line #{"%06d" % n.lineno}" if n.respond_to?(:lineno) &&
    !n.lineno.nil? && !n.lineno.empty?
  return "XML Line #{"%06d" % n.line}" if n.respond_to?(:line) &&
    !n.line.nil?
  return "ID #{n.id}" if n.respond_to?(:id) && !n.id.nil?
  while !n.nil? &&
      (!n.respond_to?(:level) || n.level.positive?) &&
      (!n.respond_to?(:context) || n.context != :section)
    n = n.parent
    return "Section: #{n.title}" if n&.respond_to?(:context) &&
      n&.context == :section
  end
  "??"
end

def initialize
  @log = {}
end

def write(file)
  File.open(file, "w:UTF-8") do |f|
    f.puts "#{file} errors"
    @log.keys.each do |key|
      f.puts "\n\n== #{key}\n\n"
      @log[key].sort do |a, b|
        a[:location] <=> b[:location]
      end.each do |n|
        loc = n[:location] ? "(#{n[:location]}): " : ""
        f.puts "#{loc}#{n[:message]}" 
        n[:context]&.split(/\n/)&.first(5)&.each { |l| f.puts "\t#{l}" }
      end
    end
  end
end