# Copyright 2022 The Fuchsia 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("//build/fidl/fidl_summary.gni")
import("//build/fidl/fidlc.gni")

# Compiles a FIDL library to IR and optionally generates API summaries.
#
# Compilation Parameters
#
#   fidl_target_name (required)
#     [string] The name of the `fidl` target declaration.
#
#   fidl_library_name (required)
#     [string] The name of the `fidl` library.
#
#   target_api_level
#     [int] Only compile APIs availble at this level. See the FIDL compiler's
#     --avalable flag for more info.
#
#   target_api_platform
#     [int] Only compile APIs available on this platform. See the FIDL
#     compiler's --available flag for more info.
#
#   gen_dir
#     [Path] If set, effectively replaces target_gen_dir. This is generally
#     used to prevent multiple fidl targets from generating the same output
#     files.
#
# Output Parameters
#
#   out_summary
#     [Path] If set, generates an API summary file at the given path.
#
#   out_json_summary
#     [Path] If set, generates a JSON API summary file at the given path.
#
#   json_representation
#     [Path] Where to generate the FIDL IR.
#
#   deps
#   public_deps
#   fidl_deps
template("fidl_ir") {
  assert(defined(invoker.fidl_target_name), "fidl_target_name is required")
  assert(defined(invoker.fidl_library_name), "fidl_library_name is required")

  out_summary = ""
  if (defined(invoker.out_summary)) {
    out_summary = invoker.out_summary
  }

  out_json_summary = ""
  if (defined(invoker.out_json_summary)) {
    out_json_summary = invoker.out_json_summary
  }

  gen_dir = target_gen_dir
  if (defined(invoker.gen_dir)) {
    gen_dir = invoker.gen_dir
  }

  json_representation = "$gen_dir/${invoker.fidl_target_name}.fidl.json"
  if (defined(invoker.json_representation)) {
    json_representation = invoker.json_representation
  }

  main_target_deps = []

  fidlc_target_name = "${target_name}_fidlc"
  fidlc(fidlc_target_name) {
    forward_variables_from(invoker,
                           [
                             "deps",
                             "experimental_flags",
                             "fidl_deps",
                             "fidl_target_name",
                             "public_deps",
                             "sources",
                             "target_api_level",
                             "target_api_platform",
                             "testonly",
                           ])
    library_name = invoker.fidl_library_name
    gen_dir = gen_dir
    json_representation = json_representation
  }

  main_target_deps += [ ":$fidlc_target_name" ]

  if (out_summary != "") {
    fidl_summary_target_name = "${target_name}_summary"
    main_target_deps += [ ":$fidl_summary_target_name" ]
    fidl_summary(fidl_summary_target_name) {
      forward_variables_from(invoker, [ "testonly" ])
      visibility = [ ":*" ]
      inputs = [ json_representation ]
      outputs = [ out_summary ]
      deps = [ ":$fidlc_target_name" ]
    }
  }

  if (out_json_summary != "") {
    fidl_summary_json_target_name = "${target_name}_summary_json"
    main_target_deps += [ ":$fidl_summary_json_target_name" ]
    fidl_summary_json(fidl_summary_json_target_name) {
      forward_variables_from(invoker, [ "testonly" ])
      inputs = [ json_representation ]
      outputs = [ out_json_summary ]
      dest = "fidl"
      deps = [ ":$fidlc_target_name" ]

      metadata = {
        compatibility_testing_goldens = [
          {
            src = rebase_path(out_json_summary, root_build_dir)
            if (!defined(invoker.target_api_level) ||
                invoker.target_api_level == "HEAD") {
              dst = rebase_path(out_json_summary, root_build_dir)
            } else {
              dst = "//sdk/history/${invoker.target_api_level}/" +
                    get_path_info(out_json_summary, "file")
            }
          },
        ]
      }
    }
  }

  group(target_name) {
    forward_variables_from(invoker, [ "testonly" ])
    public_deps = main_target_deps
    deps = main_target_deps
  }
}