# Copyright 2018 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/banjo/toolchain.gni")
import("//build/compiled_action.gni")
import("//build/sdk/sdk_atom.gni")

# Private template to generate an SDK Atom for banjo_library and
# banjo_dummy_library targets.
#

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

  # Process sources.
  file_base = "banjo/$library_name"
  all_files = []
  sdk_sources = []
  foreach(source, invoker.sources) {
    relative_source = rebase_path(source, ".")
    if (string_replace(relative_source, "..", "bogus") != relative_source) {
      # If the source file is not within the same directory, just use the file
      # name.
      relative_source = get_path_info(source, "file")
    }
    destination = "$file_base/$relative_source"
    sdk_sources += [ destination ]
    all_files += [
      {
        source = rebase_path(source)
        dest = destination
      },
    ]
  }

  # Identify metadata for dependencies.
  sdk_metas = []
  sdk_deps = []
  all_deps = []
  if (defined(invoker.deps)) {
    all_deps = invoker.deps
  }
  foreach(dep, all_deps) {
    full_label = get_label_info(dep, "label_no_toolchain")
    sdk_dep = "${full_label}_sdk"
    sdk_deps += [ sdk_dep ]
    gen_dir = get_label_info(sdk_dep, "target_gen_dir")
    name = get_label_info(sdk_dep, "name")
    sdk_metas += [ rebase_path("$gen_dir/$name.meta.json") ]
  }

  # Generate the library metadata.
  meta_file = "$target_gen_dir/${target_name}.sdk_meta.json"
  meta_target_name = "${target_name}_meta"

  action(meta_target_name) {
    script = "//build/banjo/gen_sdk_meta.py"

    inputs = sdk_metas

    outputs = [
      meta_file,
    ]

    args = [
             "--out",
             rebase_path(meta_file),
             "--name",
             library_name,
             "--root",
             file_base,
             "--specs",
           ] + sdk_metas + [ "--sources" ] + sdk_sources

    deps = sdk_deps
  }

  sdk_atom("${target_name}_sdk") {
    id = "sdk://banjo/$library_name"

    category = invoker.sdk_category

    meta = {
      source = meta_file
      dest = "$file_base/meta.json"
      schema = "banjo_library"
    }

    files = all_files

    non_sdk_deps = [ ":$meta_target_name" ]

    deps = []
    foreach(dep, all_deps) {
      label = get_label_info(dep, "label_no_toolchain")
      deps += [ "${label}_sdk" ]
    }
  }
}

# Generates some representation of a Banjo library that's consumable by Language
# bindings generators.
#
# The parameters for this template are defined in //build/banjo/banjo.gni. The
# relevant parameters in this template are:
#   - name;
#   - sources;
#   - sdk_category.

template("banjo_library") {
  assert(
      current_toolchain == banjo_toolchain,
      "This template can only be used in the Banjo toolchain $banjo_toolchain.")

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

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

  response_file = "$target_gen_dir/$target_name.args"
  ddk_root = string_replace(string_replace(library_name, ".", "/"), "_", "-")
  ddktl_root = string_replace(ddk_root, "ddk", "ddktl")
  ddk_header = "$root_gen_dir/$ddk_root.h"
  ddktl_header = "$root_gen_dir/$ddktl_root.h"
  ddktl_internal_header = "$root_gen_dir/$ddktl_root-internal.h"

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

  all_deps = []
  if (defined(invoker.deps)) {
    all_deps += invoker.deps
  }
  if (defined(invoker.public_deps)) {
    all_deps += invoker.public_deps
  }

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

    script = "//build/banjo/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),
             "--ddk-header",
             rebase_path(ddk_header, root_build_dir),
             "--ddktl-header",
             rebase_path(ddktl_header, root_build_dir),
             "--name",
             library_name,
             "--sources",
           ] + rebase_path(sources, root_build_dir)

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

      foreach(dep, all_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)
    }
  }

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

    visibility = [ ":*" ]

    tool = "//zircon/public/tool/banjoc"

    inputs = [
      response_file,
    ]

    outputs = [
      ddk_header,
      ddktl_header,
      ddktl_internal_header,
    ]

    rebased_response_file = rebase_path(response_file, root_build_dir)

    args = [ "@$rebased_response_file" ]

    deps = [
      ":$response_file_target_name",
    ]
  }

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

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

  if (defined(invoker.sdk_category) && invoker.sdk_category != "excluded") {
    _banjo_library_sdk("$target_name") {
      forward_variables_from(invoker, "*")
    }
  }
}

template("banjo_dummy_library") {
  assert(
      current_toolchain == banjo_toolchain,
      "This template can only be used in the Banjo toolchain $banjo_toolchain.")

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

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

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

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

    script = "//build/banjo/gen_response_file.py"

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

    response_file = "$target_gen_dir/$main_target_name.args"
    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),
             "--name",
             library_name,
             "--sources",
           ] + rebase_path(sources, root_build_dir)
  }

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

    public_deps = [
      ":$response_file_target_name",
    ]
  }

  if (defined(invoker.sdk_category) && invoker.sdk_category != "excluded") {
    _banjo_library_sdk("$target_name") {
      forward_variables_from(invoker, "*")
    }
  }
}