# Copyright 2019 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("$zx/public/gn/build_api_module.gni")
import("$zx/public/gn/config/standard.gni")
import("$zx/public/gn/toolchain/c_utils.gni")
import("$zx/public/gn/toolchain/environment_redirect.gni")
import("$zx/public/gn/zbi.gni")

declare_args() {
  # Whether to include all the Zircon tests in the main standalone ZBI.
  # TODO(mcgrathr): This will be replaced by a more sophisticated plan for
  # what images to build rather than a single "everything" image that needs
  # to be pared down.
  tests_in_image = true

  # Defines the `//:default` target: what `ninja` with no arguments does.
  default_deps = [
    ":build-tests",
    ":ids",
    ":images",
    ":tools",
  ]
}

# Build the native host tools intended for developer use.
_tools_targets = [ "tools" ]
foreach(host, standard_build_hosts) {
  _tools_targets += [ "tools-${host.os}-${host.cpu}" ]
  environment_redirect("tools-${host.os}-${host.cpu}.redirect") {
    visibility = [ ":*" ]
    testonly = true
    environment_label = "$zx/public/gn/toolchain:host"
    cpu = host.cpu
    os = host.os
    direct = true
    deps = [
      "$zx/system/host:tools",
    ]
  }
}

group("tools.redirect") {
  visibility = [ ":*" ]
  testonly = true
  public_deps = [
    ":tools-${host_os}-${host_cpu}",
  ]
}

if (current_toolchain == default_toolchain) {
  # Install the host developer tools for the running host platform in the
  # "$root_build_dir/tools/" directory.
  foreach(tools_target, _tools_targets) {
    tools_rspfile = "$target_gen_dir/${tools_target}.rsp"
    generated_file("$tools_target.rsp") {
      visibility = [ ":$tools_target" ]
      testonly = true
      outputs = [
        tools_rspfile,
      ]
      deps = [
        ":$tools_target.redirect",
      ]
      output_conversion = "list lines"
      data_keys = [ "tool_executables" ]
    }

    action(tools_target) {
      testonly = true
      deps = [
        ":$tools_target.rsp",
      ]
      script = "$zx/scripts/copy-files"
      depfile = "$target_out_dir/$target_name.d"
      outputs = [
        depfile,
      ]
      sources = [
        tools_rspfile,
      ]
      args = [
        tools_target,
        rebase_path(depfile, root_build_dir),
        rebase_path(tools_rspfile, root_build_dir),
      ]
    }
  }

  # Make ninja aliases for e.g. bootloader that gets all bootloader-$cpu.
  top_level_redirects = [
    "bootloader",
    "kernel",
  ]
  foreach(name, top_level_redirects) {
    group(name) {
      deps = []
      foreach(cpu, standard_fuchsia_cpus) {
        deps += [ ":$name-$cpu" ]
      }
    }

    foreach(cpu, standard_fuchsia_cpus) {
      environment_redirect("$name-$cpu") {
        environment_label = "$zx/public/gn/toolchain:user"
        cpu = cpu
        direct = true
        deps = [
          name,
        ]
      }
    }
  }

  # TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
  # GN build.
  host_tests_rspfile = "$target_gen_dir/host_tests.rsp"
  generated_file("host_tests.rsp") {
    testonly = true
    visibility = [ ":legacy-host_tests" ]
    outputs = [
      host_tests_rspfile,
    ]
    deps = [
      "system/utest:host",
    ]
    output_conversion = "list lines"
    data_keys = [ "link_output" ]
    walk_keys = [ "link_barrier" ]
  }

  action("legacy-host_tests") {
    testonly = true
    deps = [
      ":host_tests.rsp",
    ]
    script = "$zx/scripts/copy-files"
    depfile = "$target_out_dir/$target_name.d"
    outputs = [
      depfile,
    ]
    sources = [
      host_tests_rspfile,
    ]
    args = [
      "host_tests",
      rebase_path(depfile, root_build_dir),
      rebase_path(host_tests_rspfile, root_build_dir),
    ]
  }

  # TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
  # GN build.

  build_api_module("legacy_dirs") {
    testonly = true
    data_keys = [ "legacy_dirs" ]
    walk_keys = [ "legacy_barrier" ]
    deps = []
    foreach(cpu, standard_fuchsia_cpus) {
      deps += [ ":legacy-$cpu" ]
    }
  }

  foreach(cpu, standard_fuchsia_cpus) {
    group("legacy-$cpu") {
      testonly = true
      deps = [
        ":ids-$cpu",
        ":legacy-aux-$cpu",
        ":legacy-host_tests",
        ":legacy-image-$cpu",
        ":legacy-tests-$cpu",
        ":legacy_targets-$cpu",
      ]
    }

    build_api_module("legacy_targets-$cpu") {
      testonly = true
      data_keys = [ "legacy_targets" ]
      walk_keys = [ "legacy_barrier" ]
      deps = [
        ":all-ulib-$cpu",
        ":tools",
        "$zx/system/banjo",
        "$zx/system/fidl",
      ]
    }

    build_api_module("legacy_sysroot-$cpu") {
      testonly = true
      data_keys = [ "legacy_sysroot" ]
      walk_keys = [ "legacy_barrier" ]
      deps = [
        ":all-ulib-$cpu",
      ]
    }
  }
}

group("default") {
  testonly = true
  deps = default_deps
}

group("all-cpu") {
  testonly = true
  deps = []
  foreach(cpu, standard_fuchsia_cpus) {
    deps += [
      ":$cpu",
      ":core-tests-$cpu",
    ]
  }
}

group("build-tests") {
  testonly = true
  deps = [
    "$zx/public/gn/toolchain:noop-test",
  ]
}

foreach(cpu, standard_fuchsia_cpus) {
  if (current_toolchain == default_toolchain) {
    zbi("core-tests-$cpu") {
      output_dir = root_build_dir
      testonly = true
      cpu = cpu
      deps = [
        ":core-tests-$cpu-deps",
      ]
    }

    zbi(cpu) {
      output_dir = root_build_dir
      testonly = true
      cpu = cpu
      deps = [
        ":everything-$cpu",
      ]

      # Since this is the top-level target people tend to use by hand
      # instead of default when they want only one architecture at a time,
      # give them tools as well since that's what they expect.
      data_deps = [
        ":tools",
      ]
    }

    zbi_input("legacy-image-$cpu") {
      output_dir = root_build_dir
      testonly = true
      cpu = cpu
      deps = [
        ":legacy-deps-$cpu",
      ]
      metadata = {
        # legacy-$cpu depends on this to get all these deps built.
        # But they shouldn't contribute metadata to the build_api_module().
        legacy_barrier = []
      }
    }

    zbi_input("legacy-tests-$cpu") {
      output_dir = root_build_dir
      testonly = true
      cpu = cpu
      deps = [
        ":legacy-tests-deps-$cpu",
      ]
    }

    # The legacy Fuchsia GN build needs to consume a manifest of libraries
    # built for ASan (and all the libraries themselves).  When the main
    # build is ASan, it needs to find the non-ASan libraries here too.
    manifest_file("legacy-aux-$cpu") {
      testonly = true
      deps = [
        ":all-ulib-$cpu",
        ":driver-deps-$cpu",
        ":instrumented-ulib-$cpu",

        # Include the tests so their libraries are in the aux manifest
        # when individual binaries are drawn from the tests manifest.
        ":legacy-tests-deps-$cpu",
      ]
      metadata = {
        # This prevents build_api_module("legacy-$cpu") from visiting the
        # ASan incarnations of all the libraries.  The legacy build wants
        # only the manifest of ASan shared libraries.  It wants the targets
        # themselves only from the primary build.
        legacy_barrier = []
      }
    }
  }

  environment_redirect("core-tests-$cpu-deps") {
    visibility = [ ":*" ]
    testonly = true
    cpu = cpu
    environment_label = "$zx/public/gn/toolchain:user"
    direct = true
    deps = [
      "kernel",
      "system/utest:core-tests",
    ]
    assert_no_deps = [
      "system/core/*",
      "system/dev/*",
    ]
  }

  environment_redirect("legacy-deps-$cpu") {
    visibility = [ ":*" ]
    testonly = true
    environment_label = "$zx/public/gn/toolchain:user"
    cpu = cpu
    deps = [
      "$zx/bootloader",
      "$zx/kernel",
      "$zx/system/core",
      "$zx/system/dev",
      "$zx/system/uapp",
      "$zx/third_party/uapp",
    ]
    metadata = {
      legacy_barrier = []
    }
  }

  environment_redirect("legacy-tests-deps-$cpu") {
    visibility = [ ":*" ]
    testonly = true
    environment_label = "$zx/public/gn/toolchain:user"
    cpu = cpu
    direct = true
    deps = [
      "$zx/system/utest",
    ]
  }

  environment_redirect("everything-$cpu") {
    visibility = [ ":*" ]
    testonly = true
    environment_label = "$zx/public/gn/toolchain:user"
    cpu = cpu
    direct = true
    deps = [
      "$zx/bootloader",
      "$zx/kernel",
      "$zx/system/core",
      "$zx/system/dev",
      "$zx/system/uapp",
      "$zx/third_party/uapp",
    ]
    if (tests_in_image) {
      deps += [ "$zx/system/utest" ]
    }
  }

  environment_redirect("all-ulib-$cpu") {
    testonly = true
    cpu = cpu
    environment_label = "$zx/public/gn/toolchain:user"
    exclude_variant_tags = [ "instrumented" ]
    deps = [
      "$zx/system/ulib",
    ]
  }

  environment_redirect("driver-deps-$cpu") {
    testonly = true
    cpu = cpu
    environment_label = "$zx/public/gn/toolchain:user"
    exclude_variant_tags = [ "instrumented" ]
    deps = [
      "$zx/system/core/devmgr:driver_deps",
    ]
  }

  environment_redirect("instrumented-ulib-$cpu") {
    testonly = true
    cpu = cpu
    environment_label = "$zx/public/gn/toolchain:user"
    deps = [
      ":instrumented-ulib-redirect",
    ]
  }
}

if (toolchain.environment == "user") {
  instrumented_variants = []
  foreach(selector, toolchain.variant_selectors) {
    if (selector.tags + [ "instrumented" ] - [ "instrumented" ] !=
        selector.tags) {
      instrumented_variants += [ selector.variant ]
      instrumented_variants -= [ selector.variant ]
      instrumented_variants += [ selector.variant ]
    }
  }
  group("instrumented-ulib-redirect") {
    testonly = true
    visibility = [ ":*" ]
    deps = []
    foreach(variant, instrumented_variants) {
      deps += [ ":instrumented-ulib-redirect.$variant" ]
    }
  }
  foreach(variant, instrumented_variants) {
    environment_redirect("instrumented-ulib-redirect.$variant") {
      testonly = true
      visibility = [ ":instrumented-ulib-redirect" ]
      variant = variant
      deps = [
        "$zx/system/ulib",
      ]
      foreach(dep, toolchain.implicit_deps) {
        if (dep == "$dep") {
          deps += [ dep ]
        } else {
          deps += dep.add
        }
      }
    }
  }
}

# This is the top-level build API module that just lists all the others.
# Each element of the list is the simple name of the API module; the
# module's contents are found at "$root_build_dir/$target_name.json".
# Type: list(string)
build_api_module("api") {
  testonly = true
  data_keys = [ "build_api_modules" ]
  deps = [
    ":buildargs",
    ":images",
  ]
}

# This just regurgitates the build arguments specified to `gn gen`.  This is
# the exact JSON representation of the settings in "$root_build_dir/args.gn".
# It does not include build arguments left to their default values.  So to
# reproduce the settings of this build, one could put in `args.gn`:
# ```
#   forward_variables_from(read_file("buildargs.json", "json"), "*")
# ```
# Type: scope
build_api_module("buildargs") {
  # The file does not exist at all if `gn gen` is run with no `--args`.  But
  # read_file() can't handle an optional file and there's no direct way to test
  # for file existence from GN.
  contents = exec_script("/bin/sh",
                         [
                           "-c",
                           "test ! -e args.gn || cat args.gn",
                         ],
                         "scope")
}

# This describes all the "image" files the build can produce.
#
# Consumers of the build should look here for the images to be built.
# The $cpu, $name, and $type fields identify the purpose of each image.
# Consumers are expected to ignore extra images they have no use for or
# whose fields they don't understand.
#
# The $path field indicates where the file is found in the build
# directory.  The presence of an image in the list means that the build
# *can* produce it, not that the build *will* produce it.  Hence,
# consumers should use $path as an explicit argument to Ninja to ensure
# that each needed image gets built.
#
# Type: list(scope)
#
#   cpu
#     Required: CPU architecture the image is for, e.g. "arm64" or "x64".
#     Type: string
#
#   name
#     Required: The primary way that this image is known to consumers.
#     Note that the name need not be unique within the images list.
#     The tuple of ($name, $type, $cpu) should be unique.
#     Type: string
#
#   label
#     Required: The GN label of the image target.
#     Type: label_with_toolchain
#
#   path
#     Required: Path to where the file is found, relative to $root_build_dir.
#     This is also the argument to Ninja that ensures this image will be built.
#     Type: path relative to $root_build_dir
#
#   type
#     Required: Type of file, e.g. "zbi".  This often corresponds to the
#     extension used on the image file name, but not always.  For many
#     miscellaneous formats, this is just "bin" and the consumer is
#     expected to understand what the particular format is for particular
#     $name, $cpu combinations.  Other types include:
#      * "zbi": the ZBI (<zircon/boot/image.h>) format
#      * "efi": an EFI executable that an EFI boot loader can load
#      * "kernel": some other format loaded by a boot loader or emulator
#      * "blk": contents to be written to a storage device or partition
#     Type: string
#
build_api_module("images") {
  testonly = true
  data_keys = [ "images" ]
  deps = [
    ":all-cpu",
  ]
}

# TODO(BLD-353): Temporary hacks for integrating with the legacy Fuchsia
# GN build.
build_api_module("legacy_images") {
  testonly = true
  data_keys = [ "images" ]
  deps = [
    ":tools",
  ]
  foreach(cpu, standard_fuchsia_cpus) {
    deps += [ ":legacy-$cpu" ]
  }
}

# This describes all the generated source files in the build.
#
# The intent is that telling Ninja to build all these individual files
# will be the minimal work sufficient for source code analysis of all
# the files described in the compilation database to be viable.
#
# Type: list(path relative to $root_build_dir)
#
build_api_module("generated_sources") {
  testonly = true
  deps = [
    ":default",
  ]
  data_keys = [ "generated_sources" ]
}

# This describes all the binaries linked by the build.
#
# This enumerates each linked binary (executable, shared library, or
# loadable/"plug-in" module).  This includes host tools, kernels, boot
# loaders, drivers, as well as normal executables.  It does not yet include
# any non-native binary formats.  This is meant to reach the entire
# dependency graph of all binaries that the build would ever produce.  Not
# every binary described is necessary actually produced by any given Ninja
# run.  Either the $debug or the $dist file for any individual binary can
# be passed to Ninja as a specific target argument to ensure it's built and
# up to date before making use of that binary.  Like all build_api_module()
# targets, the top-level "binaries" target serves as a Ninja target to
# request that every binary described be built.
#
# Type: list(scope)
#
#   cpu
#     Required: CPU architecture the binary is for, e.g. "arm64" or "x64".
#     Type: string
#
#   os
#     Required: OS the binary is for, e.g. "fuchsia", "linux", or "mac".
#     Type: string
#
#   environment
#     Required: The ${toolchain.environment} name of what specific
#     execution this was built for, e.g. "user", "host", "guest".  The
#     tuple of ($cpu, $os, $environment) should indicate what hardware and
#     software environment this binary is compatible with.
#     Type: string
#
#   label
#     Required: The GN label of the binary target.
#     Type: label_with_toolchain
#
#   type
#     Required: The type of binary.
#     Type: "executable" or "shared_library" or "loadable_module"
#
#   debug
#     Required: Path to where the unstripped or separate debug file is
#     found, relative to $root_build_dir.  If $dist is omitted, this
#     is also the file that is used at runtime.
#     Type: path relative to $root_build_dir
#
#   dist
#     Optional: Path to where the stripped binary for deployment/execution is
#     found, relative to $root_build_dir.  This binary may be required for
#     some debugging tasks if $debug is a separate debug file rather than
#     an unstripped file.  It should exactly match the binary that will be
#     seen on devices or run directly on hosts.
#     Type: path relative to $root_build_dir
#
#   elf_build_id
#     **TODO(mcgrathr): This is not actually produced yet.**
#     Optional: Path to a file containing the lowercase ASCII hexadecimal
#     representation of the ELF build ID in this binary.  This is omitted
#     for OS environments that don't use ELF.  For an ELF binary that
#     doesn't have a build ID note, this key will be present but point to
#     an empty file.
#     Type: path relative to $root_build_dir
#
build_api_module("binaries") {
  testonly = true
  deps = [
    # TODO(mcgrathr): Need a //:everything distinct from default.
    ":default",
  ]
  data_keys = [ "binaries" ]
}

# This describes pre-generated FIDL bindings that are required by the build.
#
# TODO(BLD-441): This will go away when fidlgen is built in this build.
# See $zx/public/gn/fidl/llcpp.gni, where the metadata is generated.
#
# Type: list(scope)
#
#   name
#     Required: The FIDL library name as it appears in FIDL source (with dots).
#     Type: string
#
#   label
#     Required: The label of the fidl_library() target.
#     Type: label_no_toolchain
#
#   json
#     Required: Path to the fidlc --json output.
#     Type: path relative to $root_build_dir
#
#   target_gen_dir
#     Required: The place in the source tree where generated files go.
#     Type: path relative to $root_build_dir
#
#   args
#     Required: Argument list for `fidlgen` if run in $root_build_dir.
#     Type: list(string)
#
build_api_module("fidl_gen") {
  testonly = true
  data_keys = [ "fidl_gen" ]
  deps = [
    ":all-cpu",
  ]
}

# TODO(TC-303): ids.txt is deprecated and will be removed.
if (current_toolchain == default_toolchain) {
  action("ids") {
    testonly = true
    outputs = [
      "$root_build_dir/ids.txt",
    ]
    deps = []
    sources = []
    foreach(cpu, standard_fuchsia_cpus) {
      deps += [ ":ids-$cpu" ]
      sources += [ "$root_build_dir/ids-$cpu.txt" ]
    }
    script = "/usr/bin/sort"
    args = [
             "-u",
             "-o",
           ] + rebase_path(outputs + sources, root_build_dir)
  }

  foreach(cpu, standard_fuchsia_cpus) {
    environment_redirect("ids-$cpu") {
      testonly = true
      cpu = cpu
      environment_label = "$zx/public/gn/toolchain:user"
      deps = [
        ":$target_name",
      ]
    }
  }
} else if (toolchain.environment == "user") {
  toolchain_utils_action("ids-$current_cpu") {
    testonly = true
    deps = [
      ":elf-$current_cpu.list",
    ]
    outputs = [
      "$root_build_dir/ids-$current_cpu.txt",
    ]
    sources = [
      "$root_build_dir/elf-$current_cpu.list",
    ]
    depfile = "${outputs[0]}.d"
    script = "$zx/scripts/gen-ids-file"
    utils = [ "readelf" ]
    args = rebase_path(outputs + [ depfile ] + sources, root_build_dir)
  }

  generated_file("elf-$current_cpu.list") {
    testonly = true
    visibility = [ ":ids-$current_cpu" ]
    outputs = [
      "$root_build_dir/elf-$current_cpu.list",
    ]
    deps = [
      ":$current_cpu($default_toolchain)",
      ":core-tests-$current_cpu($default_toolchain)",
      ":tools($default_toolchain)",
    ]
    data_keys = [ "elf_link_output" ]
  }
}