# Copyright 2017 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/json/validate_json.gni")
import("//build/python/python_action.gni")
import("//build/sdk/config.gni")

# Defines a group of SDK elements.
#
# Parameters
#
#   category (required)
#     Describes the minimum category that atoms in this molecule must have.
#     See //build/sdk/sdk_atom.gni for possible values.
#
#   output_name (optional)
#     Name of the internal manifest generated by this target, without
#     an `.sdk` suffix. Defaults to target_name.
#
#   deps (optional)
#     List of GN labels referencing the elements of this group.
#     These labels must point to "sdk_atom" or "sdk_molecule" targets.
#
#   non_sdk_deps (optional)
#     List of GN labels which this target needs built.
#
#   host_tools_deps (optional)
#     A list of sdk_atom() and sdk_molecule() targets that will be walked to
#     collect all SDK host tool atom dependencies for this collection.
#     Unlike `deps`, this is only walked when host tools are included in the
#     current build configuration.

template("sdk_molecule") {
  assert(defined(invoker.category), "Must define an SDK category")

  gn_deps = []

  if (defined(invoker.deps)) {
    gn_deps += invoker.deps
  }

  # Only build host tools in the main build to save considerable build time.
  if (defined(invoker.host_tools_deps)) {
    if (sdk_inside_sub_build) {
      not_needed(invoker.host_tools_deps)
    } else {
      gn_deps += invoker.host_tools_deps
    }
  }

  # Add manifests for all of the SDK deps before adding the non-SDK deps.
  dep_manifests = []
  foreach(dep, gn_deps) {
    gen_dir = get_label_info(dep, "target_gen_dir")
    name = get_label_info(dep, "name")
    dep_manifests += [ "$gen_dir/$name.sdk" ]
  }

  if (defined(invoker.non_sdk_deps)) {
    gn_deps += invoker.non_sdk_deps
  }

  output_name = target_name
  if (defined(invoker.output_name)) {
    output_name = invoker.output_name
  }

  labels = {
    manifest = "${target_name}.manifest"
    validate = "${target_name}.validate"
  }

  files = {
    manifest = "$target_gen_dir/$output_name.sdk"
    areas = "//docs/contribute/governance/areas/_areas.yaml"
  }

  # Builds a manifest representing members of the group.
  python_action(labels.manifest) {
    forward_variables_from(invoker,
                           [
                             "assert_no_deps",
                             "testonly",
                             "visibility",
                           ])

    binary_label = "//build/sdk:create_molecule_manifest"

    deps = gn_deps

    inputs = dep_manifests + [ files.areas ]

    outputs = [ files.manifest ]

    args = [
             "--category",
             invoker.category,
             "--areas-file-path",
             rebase_path(files.areas, root_build_dir),
             "--out",
             rebase_path(files.manifest, root_build_dir),
             "--deps",
           ] + rebase_path(dep_manifests, root_build_dir)
  }

  # Verifies that the manifest is valid.
  validate_json(labels.validate) {
    forward_variables_from(invoker,
                           [
                             "testonly",
                             "visibility",
                           ])

    data = files.manifest

    schema = "//build/sdk/manifest_schema.json"

    use_valico = true

    deps = [ ":${labels.manifest}" ]
  }

  group(target_name) {
    forward_variables_from(invoker,
                           [
                             "assert_no_deps",
                             "testonly",
                             "visibility",
                           ])
    public_deps = [ ":${labels.manifest}" ]
    deps = [ ":${labels.validate}" ]
  }
}