# 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/dist/component_manifest_resources.gni")
import("//tools/cmc/build/cmc.gni")

# Defines a new root realm.
#
# The core realm on Fuchsia is a packaged non-executable component that holds
# most of the interesting packaged CFv2 components. It can vary per-product to
# encode product specific differences in the component instance tree. Since
# there are different versions of it, the root component needs to change its
# child declaration for the core realm to contain the correct URL.
#
# This template generates a new root realm containing a custom child declaration
# for core.
#
# Parameters
#
#   core_package_name (required)
#     The name of the package holding the core realm on this product. This
#     package name should be unique across all products, and thus usually is set
#     to "core-$PRODUCT_NAME", for example "core-workstation" or "core-core".
#
#   testonly
#   visibility
template("root_realm") {
  assert(
      defined(invoker.core_package_name),
      "The `core_package_name` argument was missing when calling root_realm($target_name)")

  core_child_shard_path =
      "${target_out_dir}/${target_name}-${invoker.core_package_name}.cml"
  write_file(
      core_child_shard_path,
      [
        "{",
        "    children: [",
        "        {",
        "            name: \"core\",",
        "            url: \"fuchsia-pkg://fuchsia.com/${invoker.core_package_name}#meta/core.cm\",",
        "            environment: \"#core-env\",",
        "            on_terminate: \"reboot\",",
        "        },",
        "    ],",
        "}",
      ])

  merged_manifest_target = "${target_name}_merged_manifest"
  cmc_merge(merged_manifest_target) {
    forward_variables_from(invoker, [ "testonly" ])
    visibility = [ ":*" ]
    output_name = "root.cml"
    sources = [
      "//src/sys/root/root-base.shard.cml",
      core_child_shard_path,
    ]
  }

  component_manifest_resources(target_name) {
    forward_variables_from(invoker, [ "testonly" ])
    sources = get_target_outputs(":${merged_manifest_target}")
    deps = [ ":${merged_manifest_target}" ]
  }
}