# Copyright (c) 2018, the Dart project authors.  Please see the AUTHORS file
# for details. All rights reserved. Use of this source code is governed by a
# BSD-style license that can be found in the LICENSE file.

import("../executable_suffix.gni")
import("dart_host_sdk_toolchain.gni")
import("prebuilt_dart_sdk.gni")

_is_fuchsia = defined(is_fuchsia_tree) && is_fuchsia_tree

if (_is_fuchsia) {
  import("//build/dart/dart.gni")
}

# This file defines templates for running and compiling Dart code during
# Dart's build.
#
# - prebuilt_dart_action()
#   Runs Dart scripts using the downloaded prebuilt Dart SDK if there is one,
#   and a built dart_bootstrap otherwise. This is the preferred method of
#   running Dart code during the build as it is much faster than using
#   dart_action() in debug and cross builds. However, prebuilt_dart_action()
#   should *not* be used to generate snapshots.
#
# - dart_action()
#   Runs Dart scripts using the binary built for runtime/bin:dart using the
#   host toolchain. It should only be used when an artifact agreeing exactly
#   with the version of the Dart VM being built must be produced, for example
#   an App-JIT snapshot. This will be slow in Debug builds, and very slow in
#   cross builds.
#
# - dart_bootstrap_action()
#   Ditto, but uses runtime/bin:dart_bootstrap.
#
# - gen_snapshot_action()
#   Runs the binary built for runtime/bin:gen_snapshot using the host
#   toolchain. It should only be used when an artifact agreeing exactly
#   with the version of the Dart VM being built must be produced.

# This assigns _dart_root the GN absolute path of the Dart repo. For example,
# in a Dart checkout, this will be "//". In a client repo it might be
# "//third_party/dart".
_dart_root = get_path_info("../..", "abspath")

template("_compiled_action") {
  assert(defined(invoker.tool), "tool must be defined for $target_name")
  assert(defined(invoker.outputs), "outputs must be defined for $target_name")
  assert(defined(invoker.args), "args must be defined for $target_name")

  action(target_name) {
    if (defined(invoker.visibility)) {
      visibility = invoker.visibility
    }

    script = "$_dart_root/build/gn_run_binary.py"

    if (defined(invoker.inputs)) {
      inputs = invoker.inputs
    } else {
      inputs = []
    }
    outputs = invoker.outputs

    # Construct the host toolchain version of the tool.
    host_tool = invoker.tool + "($dart_host_toolchain)"

    # Get the path to the executable. Currently, this assumes that the tool
    # does not specify output_name so that the target name is the name to use.
    # If that's not the case, we'll need another argument to the script to
    # specify this, since we can't know what the output name is (it might be in
    # another file not processed yet).
    host_executable =
        get_label_info(host_tool, "root_out_dir") + "/" +
        get_label_info(host_tool, "name") + executable_suffix

    # Add the executable itself as an input.
    inputs += [ host_executable ]

    deps = [
      host_tool,
    ]
    if (defined(invoker.deps)) {
      deps += invoker.deps
    }

    if (defined(invoker.depfile)) {
      depfile = invoker.depfile
    }

    # The "compiled_action" argument to gn_run_binary.py indicates that
    # it will exit with a non-zero status when the target program does.
    args = [
             "compiled_action",
             rebase_path(host_executable, root_build_dir),
           ] + invoker.args
  }
}

template("_prebuilt_tool_action") {
  assert(defined(invoker.binary),
      "The path to where the prebuilt binary lives must be defined")
  assert(defined(invoker.target),
      "The target to use if the prebuilt doesn't exist must be defined")

  vm_args = []
  if (defined(invoker.vm_args)) {
    vm_args += invoker.vm_args
  }

  if (_is_fuchsia || prebuilt_dart_exe_works) {
    not_needed(invoker, ["target"])
    action(target_name) {
      forward_variables_from(invoker, [
          "outputs",
          "deps",
          "visibility",
          "depfile",
      ])
      script = "$_dart_root/build/gn_run_binary.py"

      inputs = []
      if (defined(invoker.inputs)) {
        inputs += invoker.inputs
      }

      if (defined(invoker.script)) {
        inputs += [ invoker.script ]
      }
      if (defined(invoker.packages)) {
        inputs += [ invoker.packages ]
      }

      args = [
        "compiled_action",
        rebase_path(invoker.binary),
      ] + vm_args
      if (defined(invoker.packages)) {
        args += [
          "--packages=" + rebase_path(invoker.packages),
        ]
      }
      if (defined(invoker.script)) {
        args += [ rebase_path(invoker.script) ]
      }
      args += invoker.args
    }
  } else {
    not_needed(invoker, ["binary"])
    _compiled_action(target_name) {
      forward_variables_from(invoker, [
          "inputs",
          "outputs",
          "deps",
          "visibility",
          "depfile",
      ])

      if (defined(invoker.script)) {
        inputs += [ invoker.script ]
      }
      if (defined(invoker.packages)) {
        inputs += [ invoker.packages ]
      }

      tool = invoker.target
      args = vm_args
      if (defined(invoker.packages)) {
        args += [
          "--packages=" + rebase_path(invoker.packages),
        ]
      }
      if (defined(invoker.script)) {
        args += [ rebase_path(invoker.script) ]
      }
      args += invoker.args
    }
  }
}

# A template for running Dart scripts during the build using the prebuilt Dart
# SDK. This should *not* be used for generating snapshots. It uses the dart
# binary from the prebuilt Dart SDK if one is available, and dart_bootstrap
# otherwise.
#
# Parameters:
#  script:
#    The un-rebased path to the Dart script.
#
# vm_args (optional):
#    Arguments to pass to the Dart VM.
#
#  args (optional):
#    The arguments to pass to the Dart script.
#
#  packages (optional):
#    The un-rebased path to the .packages file.
#
#  Forwarded to action() with the usual meaning:
#    depfile
#    deps
#    inputs
#    outputs
#    visibility
template("prebuilt_dart_action") {
  assert(defined(invoker.script), "script must be defined for $target_name")
  assert(defined(invoker.outputs), "outputs must be defined for $target_name")
  assert(defined(invoker.args), "args must be defined for $target_name")
  assert(!defined(invoker.sources),
         "prebuilt_dart_action doesn't take a sources arg. Use inputs instead.")

  _prebuilt_tool_action(target_name) {
    forward_variables_from(invoker, "*")
    if (_is_fuchsia) {
      binary = prebuilt_dart
    } else {
      binary =
          "$_dart_root/tools/sdks/$host_os/dart-sdk/bin/dart$executable_suffix"
    }
    target = "$_dart_root/runtime/bin:dart_bootstrap"
  }
}

if (_is_fuchsia) {
template("_prebuilt_gen_snapshot_action") {
  _prebuilt_tool_action(target_name) {
    forward_variables_from(invoker, "*")
    binary = prebuilt_gen_snapshot
    target = "error"
  }
}
}

# This template runs the specified tool produced by the in-progress build.
#
# Parameters:
#  tool:
#    The target of the tool to run.
#
#  script (optional):
#    The un-rebased path to the Dart script.
#
#  vm_args (optional):
#    Arguments to pass to the Dart VM.
#
#  args (optional):
#    The arguments to pass to the Dart script.
#
#  packages (optional):
#    The un-rebased path to the .packages file.
#
#  Forwarded to action() with the usual meaning:
#    depfile
#    deps
#    inputs
#    outputs
#    visibility
template("_built_tool_action") {
  assert(defined(invoker.tool), "tool must be defined for $target_name")
  assert(defined(invoker.outputs), "outputs must be defined for $target_name")
  assert(defined(invoker.args), "args must be defined for $target_name")
  assert(!defined(invoker.sources),
         "sources arg not supported for $target_name. Use inputs instead.")

  vm_args = []
  if (defined(invoker.vm_args)) {
    vm_args += invoker.vm_args
  }

  _compiled_action(target_name) {
    forward_variables_from(invoker, [
        "depfile",
        "deps",
        "inputs",
        "outputs",
        "tool",
        "visibility",
    ])

    if (!defined(invoker.inputs)) {
      inputs = []
    }
    if (defined(invoker.script)) {
      inputs += [ invoker.script ]
    }
    if (defined(invoker.packages)) {
      inputs += [ invoker.packages ]
    }

    args = vm_args
    if (defined(invoker.packages)) {
      args += [ "--packages=" + rebase_path(invoker.packages) ]
    }
    if (defined(invoker.script)) {
      args += [ rebase_path(invoker.script) ]
    }
    args += invoker.args
  }
}

# This template runs the Dart VM produced by the in-progress build.
#
# Parameters:
#  script:
#    The un-rebased path to the Dart script.
#
#  vm_args (optional):
#    Arguments to pass to the Dart VM.
#
#  args (optional):
#    The arguments to pass to the Dart script.
#
#  packages (optional):
#    The un-rebased path to the .packages file.
#
#  Forwarded to action() with the usual meaning:
#    depfile
#    deps
#    inputs
#    outputs
#    visibility
template("dart_action") {
  assert(defined(invoker.script), "script must be defined for $target_name")
  if (!_is_fuchsia || !use_prebuilt_dart_sdk) {
    _built_tool_action(target_name) {
      tool = "$_dart_root/runtime/bin:dart"
      forward_variables_from(invoker, [
        "args",
        "depfile",
        "deps",
        "inputs",
        "outputs",
        "packages",
        "script",
        "tool",
        "visibility",
        "vm_args",
      ])
    }
  } else {
    prebuilt_dart_action(target_name) {
      forward_variables_from(invoker, "*")
    }
  }
}

# This template runs the dart_bootstrap produced by the in-progress build.
#
# Parameters:
#  script:
#    The un-rebased path to the Dart script.
#
#  vm_args (optional):
#    Arguments to pass to the Dart VM.
#
#  args (optional):
#    The arguments to pass to the Dart script.
#
#  packages (optional):
#    The un-rebased path to the .packages file.
#
#  Forwarded to action() with the usual meaning:
#    depfile
#    deps
#    inputs
#    outputs
#    visibility
template("dart_bootstrap_action") {
  assert(defined(invoker.script), "script must be defined for $target_name")
  if (!_is_fuchsia || !use_prebuilt_dart_sdk) {
    _built_tool_action(target_name) {
      tool = "$_dart_root/runtime/bin:dart_bootstrap"
      forward_variables_from(invoker, [
        "args",
        "depfile",
        "deps",
        "inputs",
        "outputs",
        "packages",
        "script",
        "tool",
        "visibility",
        "vm_args",
      ])
    }
  } else {
    # We already have a prebuilt dart at the right version, so there is no
    # reason to use dart_bootstrap.
    prebuilt_dart_action(target_name) {
      forward_variables_from(invoker, "*")
    }
  }
}

# This template runs the gen_snapshot produced by the in-progress build.
#
# Parameters:
#  vm_args (optional):
#    Arguments to pass to the Dart VM.
#
#  args (optional):
#    The arguments to pass to the Dart script.
#
#  packages (optional):
#    The un-rebased path to the .packages file.
#
#  Forwarded to action() with the usual meaning:
#    depfile
#    deps
#    inputs
#    outputs
#    visibility
template("gen_snapshot_action") {
  assert(!defined(invoker.script),
      "script must not be defined for $target_name. If there is a script use args instead.")
  if (!_is_fuchsia || !use_prebuilt_dart_sdk) {
    _built_tool_action(target_name) {
      tool = "$_dart_root/runtime/bin:gen_snapshot"
      forward_variables_from(invoker, [
        "args",
        "depfile",
        "deps",
        "inputs",
        "outputs",
        "packages",
        "tool",
        "visibility",
        "vm_args",
      ])
    }
  } else {
    _prebuilt_gen_snapshot_action(target_name) {
      forward_variables_from(invoker, "*")
    }
  }
}