json_syntax_check

#!/usr/bin/env ruby
# frozen_string_literal: true

require 'find'
require 'json'

# JSON checker calling module
module JSONChecker
  def self.run(argv)
    patterns = argv
    checker = Checker.new(patterns)
    failures = checker.run
    File.open(ENV.fetch('GITHUB_OUTPUT', './test_output'), 'a') do |f|
      f.puts "failed_files=#{JSON.dump(failures.map(&:file))}"
    end
    if failures.empty?
      puts "No file has JSON syntax error (of #{checker.files.length} files)"
    else
      puts "Files below has/have JSON syntax error (of #{checker.files.length} files)"
      failures.each do |f|
        puts "- #{f.file}: #{f.hint}"
      end
    end
    failures.length
  end
end

# Syntax failure
class Failure
  attr_reader :file, :hint

  def initialize(file, hint)
    @file = file
    @hint = hint
  end
end

# JSON checker class
class Checker
  def initialize(patterns)
    @patterns = patterns.map { |pat| Regexp.compile(pat) }
    @files = nil
    @base = ENV.fetch('BASE', ENV.fetch('GITHUB_WORKSPACE'))
    @debug = ENV.fetch('DEBUG', '0') != '0'
  end

  def files
    return @files unless @files.nil?

    @files = []
    Find.find(@base) do |file|
      next unless File.file?(file)

      next unless @patterns.any? { |pat| pat.match?(file) }

      @files << file
    end
    puts "base=#{@base} ptns=#{@patterns} files=#{@files}" if @debug

    @files
  end

  def run
    failures = files.map { |f| validate_json(f) }
    failures.compact
  end

  def validate_json(file)
    JSON.parse(File.read(file))
  rescue JSON::ParserError => e
    hint = e.message.lines.first.chomp unless e.message.lines.nil?
    hint += "' ..." if e.message.lines.length > 1

    hint ||= 'Unknown JSON parse error'
    Failure.new(file, hint)
  else
    nil
  end
end

exit JSONChecker.run(ARGV)