# frozen_string_literal: true

# typed: true

module CodeOwnership
  module Private
    module OwnershipMappers
      class TeamGlobs
        extend T::Sig
        include Interface

        @@map_files_to_owners = T.let(@map_files_to_owners, T.nilable(T::Hash[String, T.nilable(::CodeTeams::Team)])) # rubocop:disable Style/ClassVars
        @@map_files_to_owners = {} # rubocop:disable Style/ClassVars
        @@codeowners_lines_to_owners = T.let(@codeowners_lines_to_owners, T.nilable(T::Hash[String, T.nilable(::CodeTeams::Team)])) # rubocop:disable Style/ClassVars
        @@codeowners_lines_to_owners = {} # rubocop:disable Style/ClassVars

        sig do
          override.
            params(files: T::Array[String]).
            returns(T::Hash[String, T.nilable(::CodeTeams::Team)])
        end
        def map_files_to_owners(files) # rubocop:disable Lint/UnusedMethodArgument
          return @@map_files_to_owners if @@map_files_to_owners&.keys && @@map_files_to_owners.keys.count > 0

          @@map_files_to_owners = CodeTeams.all.each_with_object({}) do |team, map| # rubocop:disable Style/ClassVars
            TeamPlugins::Ownership.for(team).owned_globs.each do |glob|
              Dir.glob(glob).each do |filename|
                map[filename] = team
              end
            end
          end
        end

        class MappingContext < T::Struct
          const :glob, String
          const :team, CodeTeams::Team
        end

        class GlobOverlap < T::Struct
          extend T::Sig

          const :mapping_contexts, T::Array[MappingContext]

          sig { returns(String) }
          def description
            # These are sorted only to prevent non-determinism in output between local and CI environments.
            sorted_contexts = mapping_contexts.sort_by{|context| context.team.config_yml.to_s }
            description_args = sorted_contexts.map do |context|
              "`#{context.glob}` (from `#{context.team.config_yml}`)"
            end

            description_args.join(', ')
          end
        end

        sig do
          returns(T::Array[GlobOverlap])
        end
        def find_overlapping_globs
          mapped_files = T.let({}, T::Hash[String, T::Array[MappingContext]])
          CodeTeams.all.each_with_object({}) do |team, map| # rubocop:disable Style/ClassVars
            TeamPlugins::Ownership.for(team).owned_globs.each do |glob|
              Dir.glob(glob).each do |filename|
                mapped_files[filename] ||= []
                T.must(mapped_files[filename]) << MappingContext.new(glob: glob, team: team)
              end
            end
          end

          overlaps = T.let([], T::Array[GlobOverlap])
          mapped_files.each do |filename, mapping_contexts|
            if mapping_contexts.count > 1
              overlaps << GlobOverlap.new(mapping_contexts: mapping_contexts)
            end
          end

          deduplicated_overlaps = overlaps.uniq do |glob_overlap|
            glob_overlap.mapping_contexts.map do |context|
              [context.glob, context.team.name]
            end
          end

          deduplicated_overlaps
        end

        sig do
          override.params(file: String).
            returns(T.nilable(::CodeTeams::Team))
        end
        def map_file_to_owner(file)
          map_files_to_owners([file])[file]
        end

        sig do
          override.returns(T::Hash[String, T.nilable(::CodeTeams::Team)])
        end
        def codeowners_lines_to_owners
          return @@codeowners_lines_to_owners if @@codeowners_lines_to_owners&.keys && @@codeowners_lines_to_owners.keys.count > 0

          @@codeowners_lines_to_owners = CodeTeams.all.each_with_object({}) do |team, map| # rubocop:disable Style/ClassVars
            TeamPlugins::Ownership.for(team).owned_globs.each do |owned_glob|
              map[owned_glob] = team
            end
          end
        end

        sig { override.void }
        def bust_caches!
          @@codeowners_lines_to_owners = {} # rubocop:disable Style/ClassVars
          @@map_files_to_owners = {} # rubocop:disable Style/ClassVars
        end

        sig { override.returns(String) }
        def description
          'Team-specific owned globs'
        end
      end
    end
  end
end