# Copyright 2021 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/config/clang/clang.gni")

# Runs clang-doc for the requested target.  Requires compdb access.
#
# Parameters
#
#   stub_file (required)
#     The name of the stub file to look for in the compilation database

template("clang_doc") {
  assert(defined(invoker.stub_file))
  forward_variables_from(invoker, [ "testonly" ])

  _main_target_name = target_name

  # Creates a compile_commands.json file with just the command line used to
  # compile the API stub file.
  _filter_compdb_target_name = "${_main_target_name}_filter_compdb"
  _stamp_file_filter = "${target_gen_dir}/${_filter_compdb_target_name}.stamp"
  _jq = "//prebuilt/third_party/jq/${host_platform}/bin/jq"
  _input_compdb = "${root_gen_dir}/compdb/compile_commands.json"

  # Output must be a directory because clang-doc can only take a directory
  # name as compdb input.
  _output_compdb_dir =
      "${target_gen_dir}/${_filter_compdb_target_name}.compdb.d"
  _output_compdb = "${_output_compdb_dir}/compile_commands.json"
  action(_filter_compdb_target_name) {
    no_output_dir_leaks = false

    script = "//sdk/ctf/plasa/run_jq_on_compdb.sh"
    inputs = [
      #"${clang_prefix}/clang-doc",
      _input_compdb,
      _jq,
      invoker.stub_file,
    ]
    outputs = [
      _output_compdb,
      _stamp_file_filter,
    ]
    args = [
      rebase_path(_stamp_file_filter, root_build_dir),
      rebase_path(_jq, root_build_dir),
      rebase_path(_input_compdb, root_build_dir),
      rebase_path(_output_compdb, root_build_dir),
      rebase_path(invoker.stub_file, target_gen_dir),
    ]
    deps = [ "//sdk/ctf/plasa:filter_compdb" ]
  }

  # Invokes clang-doc only on the API stub file.
  _clang_doc_invocation_target = "${_main_target_name}_clang_doc_invoke"
  _stamp_file = "${target_gen_dir}/${_clang_doc_invocation_target}.stamp"
  _out_path = "${target_gen_dir}/${_filter_compdb_target_name}.api.d"
  _clang_diagnosis_file = "${_output_compdb_dir}/stdout"
  action(_clang_doc_invocation_target) {
    no_output_dir_leaks = false

    script = "//sdk/ctf/plasa/run_clang_doc.sh"
    inputs = [
      "${clang_prefix}/clang-doc",
      _output_compdb,
      invoker.stub_file,
    ]
    outputs = [
      _stamp_file,
      _out_path,
      _clang_diagnosis_file,
    ]
    _out_dir = rebase_path(_out_path, root_build_dir)
    _compdb_dir = rebase_path(_output_compdb_dir, root_build_dir)
    args = [
      # run script args
      rebase_path(_stamp_file, root_build_dir),
      _out_dir,
      rebase_path(_clang_diagnosis_file, root_build_dir),

      # the actual program to run
      "${rebased_clang_prefix}/clang-doc",
      "--public",
      "--format=yaml",
      "-p=${_compdb_dir}",
      "--output=${_out_dir}",

      # these should be files in the compdb.
      rebase_path(invoker.stub_file, root_build_dir),
    ]
    deps = [ ":${_filter_compdb_target_name}" ]
    if (defined(invoker.deps)) {
      deps += invoker.deps
    }
  }

  group(_main_target_name) {
    deps = [ ":${_clang_doc_invocation_target}" ]
  }
}