#!/usr/bin/env ruby
# Copyright (c) 2023 Yegor Bugayenko
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the 'Software'), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

STDOUT.sync = true

require 'slop'
require 'loog'
require 'octokit'
require 'nokogiri'
require 'backtrace'
require 'fileutils'
require 'obk'
require_relative '../lib/fief/version'
require_relative '../lib/fief/repos'

loog = Loog::REGULAR

def config(path)
  f = File.expand_path(path)
  args = []
  args += File.readlines(f).map(&:strip).reject { |a| a.empty? } if File.exist?(f)
  args
end

args = config('~/.fief') + config('.fief') + ARGV

opts = Slop.parse(args, strict: true, help: true) do |o|
  o.banner = "Usage (#{Fief::VERSION}): fief [options]"
  o.bool '-h', '--help', 'Show these instructions'
  o.bool '--version', 'Show current version'
  o.bool '--verbose', 'Print as much log messages as possible'
  o.bool '--dry', 'Make no real round trips to GitHub'
  o.bool '--reuse', 'Don\'t fetch from GitHub, reuse the existing XML file'
  o.integer '--delay', 'Delay between HTTP calls to GitHub API, in milliseconds', default: 1000
  o.string '--to', 'Directory where to save all files to', default: './fief'
  o.string '--token', 'GitHub authentication token'
  o.array '--metrics', 'Names of metrics to use (all by default)'
  o.array '--include', 'Mask of GitHub repo to include, e.g. yegor256/*'
  o.array '--exclude', 'Mask of GitHub repo to exclude'
end

if opts.help?
  puts opts
  exit
end

if opts.verbose?
  loog = Loog::VERBOSE
end

if opts.version?
  loog.info(Fief::VERSION)
  exit
end

Encoding.default_external = Encoding::UTF_8
Encoding.default_internal = Encoding::UTF_8

def build_xml(opts, loog)
  start = Time.now
  if opts.token?
    api = Octokit::Client.new(:access_token => opts[:token])
  else
    api = Octokit::Client.new
    loog.warn("Connecting to GitHub without a token, this may lead to errors, use --token")
  end
  api.auto_paginate = true
  api = Obk.new(api, pause: opts[:delay])
  repos = [ 'yegor256/fief' ]
  if !opts[:dry]
    repos = Fief::Repos.new(opts, api, loog).all
  end
  data = []
  legend = {}
  repos.each do |repo|
    Dir[File.join(__dir__, '../lib/fief/metrics/*.rb')].each do |f|
      name = File::basename(f).split('.')[0]
      if !opts[:metrics].empty? && !opts[:metrics].include?(name)
        loog.info("Ignoring #{user}/#{name} due to --metrics")
        next
      end
      type = "Fief::#{name.capitalize}"
      loog.info("Reading '#{name}' for #{repo}...")
      require_relative f
      m = type.split('::').reduce(Module, :const_get).new(api, repo, opts)
      if opts.dry?
        measures = [{ title: 'Pulls+', value: 42, legend: 'Open pulls' }, { title: 'Issues', value: 42 }]
      else
        measures = m.take(loog)
      end
      measures.each do |m|
        legend[m[:title]] = m[:legend]
      end
      if data.find { |d| d[:name] == repo }.nil?
        data << {name: repo, metrics: []}
      end
      data.find { |d| d[:name] == repo }[:metrics] += measures
      loog.info("Read from '#{name}': #{measures.map { |m| "#{m[:title]}=#{m[:value]}" }.join(', ')}")
    end
  end
  p data
  builder = Nokogiri::XML::Builder.new(:encoding => 'UTF-8') do |xml|
    xml.fief(time: Time.now, sec: Time.now - start) do
      xml.titles do
        data.map { |r| r[:metrics].map { |ms| ms[:title] } }.flatten.uniq.each do |t|
          xml.title do
            xml.text t
          end
        end
      end
      xml.legend do
        legend.each do |t, text|
          xml.column(title: t) do
            xml.text text
          end
        end
      end
      xml.repositories do
        data.each do |r|
          xml.repository(id: r[:name]) do
            xml.metrics do
              r[:metrics].each do |ms|
                xml.m(id: ms[:title]) do
                  xml.parent.set_attribute('alert', 'yes') if ms[:alert]
                  xml.text ms[:value]
                end
              end
            end
          end
        end
      end
    end
  end
  xml = builder.to_xml
  loog.debug(xml)
  xml
end
begin
  raise 'At least one --include is required' if opts[:include].empty?
  home = File.absolute_path(opts[:to])
  loog.debug("All files generated will be saved to #{home}")
  if File.exist?(home)
    loog.debug("Directory #{home} exists")
  else
    FileUtils.mkdir_p(home)
    loog.debug("Directory #{home} created")
  end
  index = File.join(home, 'index.xml')
  if opts[:reuse]
    xml = File.read(index)
  else
    xml = build_xml(opts, loog)
    File.write(index, xml)
    loog.debug("XML saved to #{index} (#{File.size(index)} bytes)")
  end
  xslt = Nokogiri::XSLT(File.read(File.join(__dir__, '../assets/index.xsl')))
  html = xslt.transform(Nokogiri::XML(xml), 'version' => "'#{Fief::VERSION}'")
  loog.debug(html)
  front = File.join(home, 'index.html')
  File.write(front, html.to_html(indent: 0).gsub("\n", ''))
  loog.debug("HTML saved to #{front} (#{File.size(front)} bytes)")
rescue StandardError => e
  loog.error(Backtrace.new(e))
  exit -1
end