# Copyright 2024 The Pigweed Authors
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may not
# use this file except in compliance with the License. You may obtain a copy of
# the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations under
# the License.
import("//build_overrides/pigweed.gni")

import("$dir_pw_build/cc_library.gni")
import("$dir_pw_build/python_action.gni")

# Generates a sensor library
#
# Args:
#   out_header: The path/to/header.h to generate
#   sources: YAML files defining sensors
#   inputs: [optional] YAML files included by the sensors, these will be
#     used to optimize re-building.
#   generator: [optional] Python generator script, if not set, the default
#     Pigweed generator will be used.
#   generator_args: [optional] Command line arguments to pass to the generator.
#   generator_includes: [optional] Include paths to pass to the generator. These
#     are used to resolve the sensor dependencies.
#   public_deps: [optional] Public dependencies to pass to the final generated
#     target.
template("pw_sensor_library") {
  current_dir = rebase_path(get_path_info(".", "abspath"))

  # Get the output header path
  assert(defined(invoker.out_header) && invoker.out_header != "",
         "pw_sensor_library requires an out_header name")
  out_header = "$target_gen_dir/${invoker.out_header}"

  # Get the source yaml files
  assert(defined(invoker.sources) && invoker.sources != [],
         "pw_sensor_library requires .yaml source files")
  source_files = []
  foreach(src, invoker.sources) {
    source_files += [ "$current_dir/$src" ]
  }

  # Get the optional inputs
  in_inputs = []
  foreach(file, invoker.inputs) {
    in_inputs += [ "$current_dir/$file" ]
  }

  # Get the include paths for the generator
  include_list = []
  foreach(file, invoker.generator_includes) {
    include_list += [
      "-I",
      rebase_path(file, root_build_dir),
    ]
  }

  # Get the generator args if provided
  generator_args = []
  if (defined(invoker.generator_args)) {
    generator_args = invoker.generator_args
  }

  # Get the generator if provided (use the default otherwise)
  if (defined(invoker.generator)) {
    generator = rebase_path(invoker.generator, root_build_dir)
  } else {
    generator =
        rebase_path("$dir_pw_sensor/py/pw_sensor/constants_generator.py")
    if (!defined(invoker.generator_args)) {
      generator_args = [
        "--package",
        "pw.sensor",
      ]
    }
  }
  generator_args_string = string_join(" ", generator_args)

  pw_python_action("${target_name}_generate_header") {
    script = "$dir_pw_sensor/py/pw_sensor/sensor_desc.py"
    python_deps = [ "$dir_pw_sensor/py" ]
    args = [] + include_list + [
             "-g",
             "python3 $generator $generator_args_string",
             "-o",
             rebase_path(out_header),
           ] + source_files
    inputs = source_files + [ generator ] + in_inputs
    outputs = [ out_header ]
  }

  config("${target_name}_config") {
    include_dirs = [ target_gen_dir ]
  }

  in_public_deps = []
  if (defined(invoker.public_deps)) {
    in_public_deps = invoker.public_deps
  }

  pw_source_set(target_name) {
    public = [ out_header ]
    public_configs = [ ":${target_name}_config" ]
    public_deps = [ ":${target_name}_generate_header" ] + in_public_deps
  }
}