discourse/bin/lint

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

require "optparse"
require "open3"
require "shellwords"
require "pathname"

PROJECT_ROOT = File.expand_path("..", __dir__)

# Runs linters directly (bundle exec rubocop/stree, pnpm lint) for files that
# live outside the core repo (e.g. plugins/*) where lefthook is not available.
class ExternalLinter
  RUBY_EXTENSIONS = %w[rb rake thor].freeze
  PRETTIER_EXTENSIONS = %w[css scss js gjs cjs mjs].freeze
  ESLINT_EXTENSIONS = %w[js gjs].freeze
  EMBER_TEMPLATE_LINT_EXTENSIONS = %w[gjs].freeze
  STYLELINT_EXTENSIONS = %w[scss].freeze

  JS_EXTENSIONS =
    (
      PRETTIER_EXTENSIONS + ESLINT_EXTENSIONS + EMBER_TEMPLATE_LINT_EXTENSIONS +
        STYLELINT_EXTENSIONS
    ).uniq.freeze

  def initialize(root, files, fix:, verbose: false)
    @root = root
    @files = files
    @fix = fix
    @verbose = verbose
  end

  def run
    ruby_files = @files.select { |f| ruby_file?(f) || File.basename(f) == "Gemfile" }
    js_files = @files.select { |f| js_file?(f) }

    success = true
    success &= run_ruby_linters(ruby_files) if ruby_files.any?
    success &= run_js_linters(js_files) if js_files.any?
    success
  end

  private

  def ruby_file?(f)
    RUBY_EXTENSIONS.include?(File.extname(f)[1..])
  end

  def js_file?(f)
    JS_EXTENSIONS.include?(File.extname(f)[1..])
  end

  def relative_paths(files)
    files.map { |f| Pathname.new(File.expand_path(f)).relative_path_from(Pathname.new(@root)).to_s }
  end

  def run_cmd(*cmd)
    puts "Running: #{cmd.shelljoin}" if @verbose
    system(*cmd)
  end

  def run_ruby_linters(files)
    rel_files = relative_paths(files)
    success = true

    Dir.chdir(@root) do
      run_cmd("bundle", "install") or abort "bundle install failed in #{@root}"

      stree_subcmd = @fix ? "write" : "check"
      stree_ok = run_cmd("bundle", "exec", "stree", stree_subcmd, *rel_files)
      success &= stree_ok unless @fix

      rubocop_args = @fix ? ["--autocorrect"] : []
      rubocop_ok = run_cmd("bundle", "exec", "rubocop", *rubocop_args, *rel_files)
      success &= rubocop_ok unless @fix
    end

    success
  end

  def run_js_linters(files)
    by_ext = ->(exts) { files.select { |f| exts.include?(File.extname(f)[1..]) } }

    prettier_files = by_ext.call(PRETTIER_EXTENSIONS)
    eslint_files = by_ext.call(ESLINT_EXTENSIONS)
    ember_template_lint_files = by_ext.call(EMBER_TEMPLATE_LINT_EXTENSIONS)
    stylelint_files = by_ext.call(STYLELINT_EXTENSIONS)

    success = true

    Dir.chdir(@root) do
      run_cmd("pnpm", "i") or abort "pnpm i failed in #{@root}"

      if prettier_files.any?
        rel = relative_paths(prettier_files)
        args = @fix ? ["--write"] : ["--list-different"]
        ok = run_cmd("pnpm", "prettier", *args, *rel)
        success &= ok unless @fix
      end

      if eslint_files.any?
        rel = relative_paths(eslint_files)
        args = @fix ? ["--fix"] : ["--quiet"]
        ok = run_cmd("pnpm", "eslint", *args, *rel)
        success &= ok unless @fix
      end

      if ember_template_lint_files.any?
        rel = relative_paths(ember_template_lint_files)
        args = @fix ? ["--fix"] : []
        ok = run_cmd("pnpm", "ember-template-lint", *args, *rel)
        success &= ok unless @fix
      end

      if stylelint_files.any?
        rel = relative_paths(stylelint_files)
        args = @fix ? ["--fix"] : []
        ok = run_cmd("pnpm", "stylelint", *args, *rel)
        success &= ok unless @fix
      end
    end

    success
  end
end

class LefthookLinter
  def initialize(options = {})
    @fix = options[:fix]
    @recent = options[:recent]
    @staged = options[:staged]
    @unstaged = options[:unstaged]
    @wip = options[:wip]
    @files = options[:files] || []
    @verbose = options[:verbose]
  end

  EVERYTHING = ["ALL FILES"]

  def run
    files = determine_files

    if @fix
      run_fix_mode(files)
    else
      run_check_mode(files)
    end
  end

  private

  def determine_files
    files =
      if @recent
        recent_files
      elsif @staged
        staged_files
      elsif @unstaged
        unstaged_files
      elsif @wip
        wip_files
      elsif !@files.empty?
        @files
      else
        return EVERYTHING
      end

    files
      .flat_map do |f|
        path = normalize_relative_path(f)
        if File.directory?(path)
          expanded =
            Dir.glob(File.join(path, "**", "*")).select { |g| File.file?(g) && lintable_file?(g) }
          abort "Error: No lintable files found in directory: #{path}" if expanded.empty?
          expanded
        else
          [path]
        end
      end
      .select { |f| File.file?(f) && lintable_file?(f) }
      .uniq
  end

  def recent_files
    log_output, status = Open3.capture2("git", "log", "-50", "--name-only", "--pretty=format:")
    return [] unless status.success?

    log_files = log_output.lines.map(&:strip).reject(&:empty?)

    tracked_out, _ = Open3.capture2("git", "ls-files")
    untracked_out, _ = Open3.capture2("git", "ls-files", "--others", "--exclude-standard")

    tracked = Set.new(tracked_out.lines.map(&:strip))
    untracked = Set.new(untracked_out.lines.map(&:strip))

    candidates = []
    log_files.each { |f| candidates << f if tracked.include?(f) }
    candidates + untracked.to_a
  end

  def staged_files
    git_output, status = Open3.capture2("git", "diff", "--cached", "--name-only")
    return [] unless status.success?
    git_output.lines.map(&:strip).reject(&:empty?)
  end

  def unstaged_files
    git_output, status = Open3.capture2("git", "diff", "--name-only")
    return [] unless status.success?
    git_output.lines.map(&:strip).reject(&:empty?)
  end

  def wip_files
    main_diff_output, _ = Open3.capture2("git", "diff", "main...HEAD", "--name-only")
    main_files = main_diff_output.lines.map(&:strip).reject(&:empty?)

    main_files + staged_files + unstaged_files
  end

  def lintable_file?(file)
    # Skip certain directories and files
    if file.include?("node_modules") || file.include?("vendor") || file.include?("tmp") ||
         file.include?(".git") || file == "config/database.yml"
      return false
    end

    return true if file == "Gemfile"

    ext = File.extname(file)[1..]

    # Check for Ruby files in /bin/ directory without extensions
    if ext.nil? || ext.empty?
      if file.start_with?("bin/") && File.file?(file)
        begin
          first_line = File.open(file, &:readline)
          return true if first_line.strip == "#!/usr/bin/env ruby"
        rescue StandardError
          return false
        end
      end
      return false
    end

    # Check if file extension is lintable
    lintable_extensions = %w[rb rake js gjs hbs scss css yml yaml thor]
    lintable_extensions.include?(ext)
  end

  def run_fix_mode(files)
    if files == EVERYTHING
      puts "Running linters in fix mode on all files" if @verbose
      run_lefthook_command("fix-all", [])
      return
    end

    if files.empty?
      puts "No files to fix, exiting."
      return
    end

    core, external = partition_files(files)
    run_lefthook_command("fix-staged", core) if core.any?
    external.each { |root, fs| ExternalLinter.new(root, fs, fix: true, verbose: @verbose).run }
  end

  def run_check_mode(files)
    if files == EVERYTHING
      puts "Running linters in check mode on all files" if @verbose
      run_lefthook_command("lints", [])
      return
    end

    if files.empty?
      puts "No files to lint, exiting."
      return
    end

    core, external = partition_files(files)
    run_lefthook_command("pre-commit", core) if core.any?
    external.each do |root, fs|
      success = ExternalLinter.new(root, fs, fix: false, verbose: @verbose).run
      exit 1 unless success
    end
  end

  def partition_files(files)
    core_files = []
    external_files = Hash.new { |h, k| h[k] = [] }

    files.each do |f|
      if (root = external_plugin_root(f))
        external_files[File.join(PROJECT_ROOT, root)] << f
      else
        core_files << f
      end
    end

    [core_files, external_files]
  end

  # Returns "plugins/<name>" if the file is in an unbundled plugin directory, else nil.
  def external_plugin_root(file)
    path = normalize_relative_path(file)
    return nil unless path.start_with?("plugins/")

    parts = path.split("/")
    return nil if parts.length < 2

    plugin_dir = "plugins/#{parts[1]}"
    bundled_plugins.include?(plugin_dir) ? nil : plugin_dir
  end

  def bundled_plugins
    @bundled_plugins ||=
      begin
        out, status = Open3.capture2(File.join(PROJECT_ROOT, "script", "list_bundled_plugins"))
        abort "Failed to list bundled plugins" unless status.success?
        Set.new(out.lines.map(&:strip).reject(&:empty?))
      end
  end

  def run_lefthook_command(hook, files)
    if !files.empty?
      normalized = files.map { |f| normalize_relative_path(f) }
      exec_lefthook(hook, nil, normalized)
    else
      exec_lefthook(hook, nil, files)
    end
  end

  def exec_lefthook(hook, command, files)
    cmd = ["pnpm", "lefthook", "run", hook]
    cmd << "--command" << command if command
    files.each { |f| cmd << "--file" << f }
    cmd << "--verbose" if @verbose

    puts "Running: #{cmd.shelljoin}" if @verbose
    exit 1 unless system({ "LEFTHOOK" => "1" }, *cmd)
  end

  def normalize_relative_path(file)
    cleaned = file.start_with?("./") ? file[2..] : file
    path = Pathname.new(cleaned)
    if path.absolute?
      begin
        path = path.relative_path_from(Pathname.new(PROJECT_ROOT))
      rescue ArgumentError
        # leave as is if it's outside the repo
      end
    end
    path.to_s
  end
end

def parse_options
  options = {}

  OptionParser
    .new do |parser|
      parser.banner = "Usage: bin/lint [options] [files|directories...]"

      parser.on("-h", "--help", "Show this help message") do
        puts parser
        puts
        puts "Examples:"
        puts "  bin/lint                        # Lint all files"
        puts "  bin/lint --recent               # Lint recently changed files"
        puts "  bin/lint --staged               # Lint only staged files"
        puts "  bin/lint --unstaged             # Lint only unstaged files"
        puts "  bin/lint --wip                  # Lint staged + unstaged + files changed since main"
        puts "  bin/lint --fix app.rb file2.js  # Fix specific file/s"
        puts "  bin/lint app/models/*.rb        # Lint multiple files"
        puts "  bin/lint frontend/discourse/app/ # Lint all lintable files in directory"
        puts
        puts "Note: This script now uses lefthook to run linters."
        puts "Check lefthook.yml for linting configuration."
        exit
      end

      parser.on("-f", "--fix", "Attempt to automatically fix issues") { options[:fix] = true }

      parser.on("-r", "--recent", "Lint recently changed files (last 50 commits)") do
        options[:recent] = true
      end

      parser.on("--staged", "Lint only staged files") { options[:staged] = true }

      parser.on("--unstaged", "Lint only unstaged files") { options[:unstaged] = true }

      parser.on("--wip", "Lint work-in-progress: staged + unstaged + files changed since main") do
        options[:wip] = true
      end

      parser.on("-v", "--verbose", "Show verbose output") { options[:verbose] = true }
    end
    .parse!

  options[:files] = ARGV unless ARGV.empty?
  options
end

if __FILE__ == $0
  options = parse_options
  linter = LefthookLinter.new(options)
  linter.run
end