extract_plist.rb

# typed: true
# frozen_string_literal: true

require "bundle_version"
require "unversioned_cask_checker"

module Homebrew
  module Livecheck
    module Strategy
      # The {ExtractPlist} strategy downloads the file at a URL and extracts
      # versions from contained `.plist` files using {UnversionedCaskChecker}.
      #
      # In practice, this strategy operates by downloading very large files,
      # so it's both slow and data-intensive. As such, the {ExtractPlist}
      # strategy should only be used as an absolute last resort.
      #
      # This strategy is not applied automatically and it's necessary to use
      # `strategy :extract_plist` in a `livecheck` block to apply it.
      #
      # @api private
      class ExtractPlist
        # A priority of zero causes livecheck to skip the strategy. We do this
        # for {ExtractPlist} so we can selectively apply it when appropriate.
        PRIORITY = 0

        # The `Regexp` used to determine if the strategy applies to the URL.
        URL_MATCH_REGEX = %r{^https?://}i.freeze

        # Whether the strategy can be applied to the provided URL.
        #
        # @param url [String] the URL to match against
        # @return [Boolean]
        sig { params(url: String).returns(T::Boolean) }
        def self.match?(url)
          URL_MATCH_REGEX.match?(url)
        end

        # @api private
        Item = Struct.new(
          # @api private
          :bundle_version,
          keyword_init: true,
        ) do
          extend Forwardable

          # @api public
          delegate version: :bundle_version

          # @api public
          delegate short_version: :bundle_version
        end

        # Identify versions from `Item`s produced using
        # {UnversionedCaskChecker} version information.
        #
        # @param items [Hash] a hash of `Item`s containing version information
        # @param regex [Regexp, nil] a regex for use in a strategy block
        # @return [Array]
        sig {
          params(
            items: T::Hash[String, Item],
            regex: T.nilable(Regexp),
            block: T.nilable(Proc),
          ).returns(T::Array[String])
        }
        def self.versions_from_items(items, regex = nil, &block)
          if block
            block_return_value = regex.present? ? yield(items, regex) : yield(items)
            return Strategy.handle_block_return(block_return_value)
          end

          items.map do |_key, item|
            item.bundle_version.nice_version
          end.compact.uniq
        end

        # Uses {UnversionedCaskChecker} on the provided cask to identify
        # versions from `plist` files.
        #
        # @param cask [Cask::Cask] the cask to check for version information
        # @param url [String, nil] an alternative URL to check for version
        #   information
        # @param regex [Regexp, nil] a regex for use in a strategy block
        # @return [Hash]
        sig {
          params(
            cask:    Cask::Cask,
            url:     T.nilable(String),
            regex:   T.nilable(Regexp),
            _unused: T.nilable(T::Hash[Symbol, T.untyped]),
            block:   T.nilable(Proc),
          ).returns(T::Hash[Symbol, T.untyped])
        }
        def self.find_versions(cask:, url: nil, regex: nil, **_unused, &block)
          if regex.present? && block.blank?
            raise ArgumentError,
                  "#{Utils.demodulize(T.must(name))} only supports a regex when using a `strategy` block"
          end
          unless T.unsafe(cask)
            raise ArgumentError, "The #{Utils.demodulize(T.must(name))} strategy only supports casks."
          end

          match_data = { matches: {}, regex: regex, url: url }

          unversioned_cask_checker = if url.present? && url != cask.url.to_s
            # Create a copy of the `cask` that uses the `livecheck` block URL
            cask_copy = Cask::CaskLoader.load(cask.sourcefile_path)
            cask_copy.allow_reassignment = true
            cask_copy.url { url }
            UnversionedCaskChecker.new(cask_copy)
          else
            UnversionedCaskChecker.new(cask)
          end

          items = unversioned_cask_checker.all_versions.transform_values { |v| Item.new(bundle_version: v) }

          versions_from_items(items, regex, &block).each do |version_text|
            match_data[:matches][version_text] = Version.new(version_text)
          end

          match_data
        end
      end
    end
  end
end