# Copyright 2013 The Flutter Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import("//flutter/tools/executable_action.gni")
import("//flutter/tools/fuchsia/fidl/fidl.gni")
import("//flutter/tools/fuchsia/fidl/toolchain.gni")
import("//flutter/tools/fuchsia/gn-sdk/config/config.gni")

# Generates some representation of a FIDL library that's consumable by Language
# bindings generators.
#
# The parameters for this template are defined in //flutter/tools/fuchsia/fidl/fidl.gni. The
# relevant parameters in this template are:
#   - name;
#   - sources.

template("fidl_library") {
  assert(
      current_toolchain == fidl_toolchain,
      "This template can only be used in the FIDL toolchain $fidl_toolchain.")

  assert(defined(invoker.sources), "A FIDL library requires some sources.")

  library_name = target_name
  if (defined(invoker.name)) {
    library_name = invoker.name
  }

  response_file = "$target_gen_dir/$target_name.args"
  fidl_stem = "$target_gen_dir/$target_name.fidl"
  json_representation = "$fidl_stem.json"

  coding_tables = "$fidl_stem.tables.c"

  main_target_name = target_name
  response_file_target_name = "${target_name}_response_file"
  compilation_target_name = "${target_name}_compile"

  # Only artifacts that have various associated FIDL generated targets.
  fidl_deps = []

  # Artifacts other than FIDL, that are also dependencies.
  non_fidl_deps = []

  if (defined(invoker.non_fidl_deps)) {
    non_fidl_deps += invoker.non_fidl_deps
  }

  if (defined(invoker.deps)) {
    fidl_deps += invoker.deps - non_fidl_deps
  }
  if (defined(invoker.public_deps)) {
    fidl_deps += invoker.public_deps
  }

  action(response_file_target_name) {
    visibility = [ ":*" ]

    script = "//flutter/tools/fuchsia/fidl/gen_response_file.py"

    forward_variables_from(invoker,
                           [
                             "deps",
                             "public_deps",
                             "sources",
                             "testonly",
                           ])

    libraries = "$target_gen_dir/$main_target_name.libraries"

    outputs = [
      response_file,
      libraries,
    ]

    args = [
             "--out-response-file",
             rebase_path(response_file, root_build_dir),
             "--out-libraries",
             rebase_path(libraries, root_build_dir),
             "--json",
             rebase_path(json_representation, root_build_dir),
             "--tables",
             rebase_path(coding_tables, root_build_dir),
             "--name",
             library_name,
             "--sources",
           ] + rebase_path(sources, root_build_dir)

    if (fidl_deps != []) {
      dep_libraries = []

      foreach(dep, fidl_deps) {
        gen_dir = get_label_info(dep, "target_gen_dir")
        name = get_label_info(dep, "name")
        dep_libraries += [ "$gen_dir/$name.libraries" ]
      }

      inputs = dep_libraries

      args += [ "--dep-libraries" ] + rebase_path(dep_libraries, root_build_dir)
    }
  }

  executable_action(compilation_target_name) {
    forward_variables_from(invoker, [ "testonly" ])

    visibility = [ ":*" ]

    tool = "$fuchsia_tool_dir/fidlc"

    inputs = [ response_file ]

    outputs = [
      coding_tables,
      json_representation,
    ]

    args = [ "@" + rebase_path(response_file, root_build_dir) ]

    deps = [ ":$response_file_target_name" ] + non_fidl_deps
  }

  group(main_target_name) {
    forward_variables_from(invoker,
                           [
                             "testonly",
                             "visibility",
                             "response_file",
                           ])

    # Metadata to allow us to query all FIDL IR files.
    metadata = {
      fidl_json = [ rebase_path(json_representation, root_build_dir) ]
      generated_sources = fidl_json
    }

    public_deps = [
      ":$compilation_target_name",
      ":$response_file_target_name",
    ]
  }
}