#!/usr/bin/env ruby
# https://rubygems.org/gems/diffy
require "diffy"

Diffy::Diff.default_options.merge!(
  include_diff_info: true,
  context: 1,
)

class Tarball
  attr_reader :version, :sha256

  def initialize(path, size, sha1, sha256, sha512)
    /\A\/(?:[^\/\n]*\/)*(?:ruby-(?<ver>(?<xy>\d+\.\d+)\.\d+(?:-(?:preview|rc)\d+)?)[0-9a-z.\-]+)/ =~ path \
      or raise "tarball path doesn't mach regexp"
    @path = path
    @size = size
    @sha1 = sha1
    @sha256 = sha256
    @sha512 = sha512
    @version = ver
    @xy = xy
  end

  def gz?;  @path.end_with?('.gz'); end
  def zip?; @path.end_with?('.zip'); end
  def bz2?; @path.end_with?('.bz2'); end
  def xz?;  @path.end_with?('.xz'); end

  def ext; @path[/(?:zip|tar\.(?:gz|bz2|xz))\z/]; end

  def to_md
    <<eom
* <https://cache.ruby-lang.org/pub/ruby/#{@xy}/ruby-#{@version}.#{ext}>

      SIZE:   #{@size} bytes
      SHA1:   #{@sha1}
      SHA256: #{@sha256}
      SHA512: #{@sha512}
eom
  end

  # * /home/naruse/obj/ruby-trunk/tmp/ruby-2.6.0-preview3.tar.gz
  #   SIZE:   17116009 bytes
  #   SHA1:   21f62c369661a2ab1b521fd2fa8191a4273e12a1
  #   SHA256: 97cea8aa63dfa250ba6902b658a7aa066daf817b22f82b7ee28f44aec7c2e394
  #   SHA512: 1e2042324821bb4e110af7067f52891606dcfc71e640c194ab1c117f0b941550e0b3ac36ad3511214ac80c536b9e5cfaf8789eec74cf56971a832ea8fc4e6d94
  def self.parse(wwwdir, file)
    ary = []
    ver = nil
    File.read(file).scan(/^\* .*(?:\n .*)*/) do |unit|
      path, size, sha1, sha256, sha512 = unit.lines.map(&:chomp)
      path.slice!(0, 2)
      size = size[/\d+/].to_i
      sha1 = sha1[/\h{40}/]
      sha256 = sha256[/\h{64}/]
      sha512 = sha512[/\h{128}/]
      tarball = Tarball.new(path, size, sha1, sha256, sha512)
      if ver
        raise "mixed versions" if tarball.version != ver
      else
        ver = tarball.version
      end
      ary << tarball
    end
    xy = ver[/\A\d+\.\d+/]
    ary.each do |tarball|
      puts tarball.to_md
    end
    update_branches_yml(ver, xy, wwwdir)
    update_downloads_yml(ver, xy, wwwdir)
    update_releases_yml(ver, xy, ary, wwwdir)
    ary
  end

  def self.update_branches_yml(ver, xy, wwwdir)
    filename = "_data/branches.yml"
    orig_data = File.read(File.join(wwwdir, filename))
    data = orig_data.dup
    if data.include?("\n- name: #{xy}\n")
      data.sub!(/\n- name: #{Regexp.escape(xy)}\n(?:  .*\n)*/) do |node|
        unless ver.include?("-")
          # assume this is X.Y.0 release
          node.sub!(/^  status: preview\n/, "  status: normal maintenance\n")
          node.sub!(/^  date:\n/, "  status: #{Time.now.year}-12-25\n")
        end
        node
      end
    else
      if ver.include?("-")
        status = "preview"
        year = nil
      else
        status = "normal maintenance"
        year = Time.now.year
      end
      entry = <<eom
- name: #{xy}
  status: #{status}
  date:#{ year && " #{year}-12-25" }
  eol_date:

eom
      data.sub!(/(?=^- name)/, entry)
    end
    if data != orig_data
      diff = Diffy::Diff.new(orig_data, data)
      show_diff(filename, diff)
    end
  end

  def self.update_downloads_yml(ver, xy, wwwdir)
    filename = "_data/downloads.yml"
    orig_data = File.read(File.join(wwwdir, filename))
    data = orig_data.dup

    if /^preview:\n\n(?:  .*\n)*  - #{Regexp.escape(xy)}\./ =~ data
      if ver.include?("-")
        data.sub!(/^  - #{Regexp.escape(xy)}\..*/, "  - #{ver}")
      else
        data.sub!(/^  - #{Regexp.escape(xy)}\..*\n/, "")
        data.sub!(/(?<=^stable:\n\n)/, "  - #{ver}\n")
      end
    else
      unless data.sub!(/^  - #{Regexp.escape(xy)}\..*/, "  - #{ver}")
        if ver.include?("-")
          data.sub!(/(?<=^preview:\n\n)/, "  - #{ver}\n")
        else
          data.sub!(/(?<=^stable:\n\n)/, "  - #{ver}\n")
        end
      end
    end
    if data != orig_data
      diff = Diffy::Diff.new(orig_data, data)
      show_diff(filename, diff)
    end
  end

  def self.update_releases_yml(ver, xy, ary, wwwdir)
    filename = "_data/releases.yml"
    orig_data = File.read(File.join(wwwdir, filename))
    data = orig_data.dup

    date = Time.now
    entry = <<eom
- version: #{ver}
  date: #{date.strftime("%Y-%m-%d")}
  post: /en/news/#{date.strftime("%Y/%m/%d")}/ruby-#{ver.tr('.', '-')}-released/
  url:
    gz:  https://cache.ruby-lang.org/pub/ruby/#{xy}/ruby-#{ver}.tar.gz
    zip: https://cache.ruby-lang.org/pub/ruby/#{xy}/ruby-#{ver}.zip
    bz2: https://cache.ruby-lang.org/pub/ruby/#{xy}/ruby-#{ver}.tar.bz2
    xz:  https://cache.ruby-lang.org/pub/ruby/#{xy}/ruby-#{ver}.tar.xz
  sha256:
    gz:  #{ary.find{|x|x.gz? }.sha256}
    zip: #{ary.find{|x|x.zip?}.sha256}
    bz2: #{ary.find{|x|x.bz2?}.sha256}
    xz:  #{ary.find{|x|x.xz? }.sha256}
eom

    if data.include?("\n- version: #{ver}\n")
    elsif data.sub!(/\n# #{Regexp.escape(xy)} series\n/, "\\&\n#{entry}")
    else
      data.sub!(/^$/, "\n# #{xy} series\n\n#{entry}")
    end
    if data != orig_data
      diff =  Diffy::Diff.new(orig_data, data)
      show_diff(filename, diff)
    end
  end

  def self.show_diff(filename, diff)
    diff.each_with_index do |line, index|
      case index
      when 0
        line.sub!(/\A--- (.*)\t(\d+-\d+-\d+ [0-9:.]+ [\-+]\d+)\Z/) do
          "--- a/#{filename}\t#{$2}"
        end
      when 1
        line.sub!(/\A\+\+\+ (.*)\t(\d+-\d+-\d+ [0-9:.]+ [\-+]\d+)\Z/) do
          "+++ b/#{filename}\t#{$2}"
        end
      end
      puts line
    end
  end
end

def main
  if ARGV.size != 2
    STDERR.puts "usage: format-release <dir-of-w.r-l.o> <output-of-make-snapshot>"
    exit
  end
  Tarball.parse(ARGV[0], ARGV[1])
end

main