#!/bin/bash
# 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.

#### CATEGORY=Build
### set up a build directory

## usage: fx set PRODUCT.BOARD [--with GNLABEL1,GNLABEL2,...]
##               [--release] [--auto-dir] [--args ARG] [--variant VARIANT]
##               [--with-base GNLABEL1,GNLABEL2,...]
##
## where PRODUCT is an entry from `//products` or `//vendor/*/products` and
## BOARD is an entry from `//boards` or `//vendor/*/boards`. Use the
## `fx list-products` and `fx list-boards` commands to see a list of
## possible products and boards (respectively). See the README.md in those
## directories for a description of the various options.
##
## BUILDDIR is the directory where the build output goes.
## If it begins with `//` or `out/` then it's taken as relative to FUCHSIA_DIR.
## Otherwise it should be an absolute path or a path relative to the current
## working directory that winds up in `FUCHSIA_DIR/out`.
## It defaults to `out/default`.
##
## This command stores the location of the build directory in the //.fx-build-dir
## file, which causes subsequent `fx` commands to use that build directory. Use
## `fx use` to switch build directories.
##
## Ensures Goma is ready (if Goma is enabled).
##
## This is a wrapper around running `gn gen --check=system BUILDDIR --args ...`.
## If GN fails with an error, `fx set` does not change anything.
##
## optional arguments:
##   --args                Additional argument to pass to gn.  If the --args
##                         argument is given multiple times, all the specified
##                         arguments are passed to gn.
##                         N.B. Arguments must be expressed using GN's syntax.
##                         In particular this means that for strings they must
##                         be quoted with double-quotes, and the quoting must
##                         survive, for example, the shell. Thus when passing
##                         an argument that takes a string, pass it with
##                         something like --args=foo='"bar"'. E.g.,
##                         bash$ fx set core.x64 --args=foo='"bar"'
##                         More complicated arguments, e.g., lists, require
##                         their own special syntax. See GN documentation
##                         for the syntax of each kind of argument.
##   --auto-dir            Act like `fx --dir out/PRODUCT.BOARD set ...`.
##   --ccache|--no-ccache  Whether to use ccache during the build. Ccache attempts
##                         to make builds faster by caching build artifacts.
##                         Defaults to detecting whether the CCACHE_DIR environment
##                         variable is set to a directory.
##   --fuzz-with           Pass a sanitizer name, e.g. "--fuzz-with asan" to
##                         enable ALL supporting fuzzers.  Use --variant for
##                         individual fuzzers, e.g. "--variant asan-fuzzer/foo".
##   --goma|--no-goma      Whether to use the goma service during the build. Goma
##                         attempts to make builds faster using remote build
##                         servers. Defaults to detecting whether goma has been
##                         set up via `fx goma`.
##   --ide                 Pass --ide=VALUE to gn when generating to create project
##                         files usable with that IDE. Useful values include "vs"
##                         for Visual Studio or "xcode" for Xcode.
##   --json-ide-script     Pass --json-ide-script=python_script to gn which runs
##                         the given python script after the JSON project file is
##                         generated when using --ide json. The path to the project
##                         file is given as the first argument to the script.
##                         The script may be a path or a gn label.
##   --netboot             Ensure that a network ramboot image is always built.
##   --no-ensure-goma      Skip ensuring that goma is started when using goma.
##   --release             an alias for "--args=is_debug=false"
##   --variant             Selects which runtime variant to use (e.g., asan) by
##                         passing a `select_variant=[VARIANT*,...]` argument
##                         to gn that collects all the --variant arguments in
##                         order. Variants are normal builds in most respects,
##                         but allow users to test different runtime settings
##                         for either the whole build or for a specific target.
##                         This can be specified by passing the variant name
##                         to this argument (e.g. `--variant asan`) for the
##                         former, or the variant name and the target name
##                         separated by a slash (e.g. `--variant asan/my_test`)
##                         for the latter.
##   --with GNLABEL        Labels of additional packages to include in the
##                         'universe' set of available packages. These packages
##                         can be run ephemerally. Multiple labels can be
##                         provided delimited by commas or the --with argument
##                         can be provided multiple times.
##   --with-base GNLABEL   Labels of additional packages to include in the
##                         'base' set of packages. These packages are included in
##                         the system image and can be updated only with an OTA.
##                         Multiple labels can be provided delimited by commas
##                         or the --with-base argument can be provided multiple
##                         times.
##   --with-cache GNLABEL  Labels of additional packages to include in the
##                         'cache' set of packages. These packages are made
##                         available on disk immediately after paving and in
##                         factory flows. These packages are not updated with
##                         an OTA, but are instead updated ephemerally. This
##                         cache of software can be evicted by the system if
##                         storage pressure arises or other policies indicate.
##                         Multiple labels can be provided delimited by commas
##                         or the --with-cache argument can be provided
##                         multiple times.
##   --with-host GNLABEL   Labels of additional host-only targets to be
##                         produced by the build. Multiple labels can be
##                         provided delimited by commas or the --with-host
##                         argument can be provided multiple times.
##   --cargo-toml-gen      Enable generation of Cargo.toml files
##   --dev                 Always recompile fx-set from source. Ignored unless
##                         the legacy_set feature is disabled.
##
## Example:
##
##   $ fx set core.x64 --with //bundles:tests
##   -> build directory: out/default
##      board: //boards/x64.gni
##      product: //products/core.gni
##      universe: //bundles:tests (all test packages)

source "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/lib/vars.sh || exit $?

set -e

function find_config {
  local config_type="$1"
  local config_name="$2"

  for directory in vendor/*/"${config_type}" "${config_type}"; do
    local guessed_config="${directory}/${config_name}.gni"
    if [[ -a "${guessed_config}" ]]; then
      echo "${guessed_config}"
      return
    fi
  done

  fx-error "Could not find a ${config_type} configuration matching \"${config_name}\""
  fx-error "Checked:"
  for directory in vendor/*/"${config_type}" "${config_type}"; do
    local guessed_config="${directory}/${config_name}.gni"
    fx-error "  ${guessed_config}"
  done
  exit 1
}

function explain-goal-argument {
  fx-error You must specify which product and which board you wish to build.
  fx-error Example:
  fx-error "  fx set core.x64"
  fx-error
  fx-error Run \"fx list-products\" to see the available products.
  fx-error Run \"fx list-boards\" to see the available boards.
  fx-error Run \"fx set --help\" to see full usage.
  fx-error Run \"fx status\" to see the current developer settings.
  return 0
}

function main {
  fx-standard-switches "$@"
  set -- "${FX_ARGV[@]}"

  # Check if the --dev flag is set. If it is, then we'll always build fx-set
  # from source.
  local dev=false
  for arg; do
    shift
    if [ "$arg" = --dev ]; then
      dev=true
      continue
    fi
    # Include every arg besides --dev in the args we pass to fx-set.
    set -- "$@" "$arg"
  done

  if ! is_feature_enabled "legacy_set"; then
    # Cache the compiled executable for later invocations.
    readonly exe_path="${FX_CACHE_DIR}/fx-set"

    readonly revision_file="${FX_CACHE_DIR}/fx-set-revision"
    local current_revision
    current_revision="$(git -C "$FUCHSIA_DIR" rev-parse HEAD)"

    # Determine whether we need to rebuild the fx-set executable. We'll only
    # rebuild if the --dev flag is set, or if the cached version of fx-set was
    # built at a revision other than the current revision. We determine that by
    # storing the current HEAD of fuchsia.git in a cached version file whenever
    # we build fx-set, and then we rebuild if the current HEAD differs from the
    # revision referenced in the cached file.
    local should_rebuild=true
    if ! $dev && [ -f "$exe_path" ] && [ -f "$revision_file" ]; then
      local fx_set_revision
      fx_set_revision="$(head -n 1 "$revision_file")"
      if [ "$fx_set_revision" = "$current_revision" ]; then
        should_rebuild=false
      fi
    fi

    if $should_rebuild; then
      # Build in a temporary directory where we can arrange the module.
      #
      # Avoid "TMPDIR" since Go looks at that environment variable.
      BUILD_DIR=$(mktemp -d)
      trap 'rm -rf $BUILD_DIR' EXIT
      pushd "$BUILD_DIR" > /dev/null
      for target in go.{mod,sum} vendor; do
        ln -s "$FUCHSIA_DIR"/third_party/golibs/$target .
      done
      ln -s "$FUCHSIA_DIR"/tools .
      if ! GOPROXY=off fx-command-run go build -o "$exe_path" ./tools/build/fx-set/cmd; then
        # TODO(fxbug.dev/68465): Remove this error handling once the Go version
        # of fx-set has been rolled out and the old `fx set` code deleted.
        if ! $dev; then # If running in dev mode, compilation failures are expected.
          fx-error "Failed to build fx set."
          fx-error "Please file a bug using \`fx report-bug set\` with the full error copy-pasted."
          fx-error "Rerun your command using the uncompiled version:"
          fx-error "  fx --enable=legacy_set set $*"
        fi
        return 1
      fi
      popd > /dev/null

      # Record the current HEAD *after* building fx-set so that we always try
      # to rebuild on subsequent attempts if compilation fails the first time.
      echo "$current_revision" > "$revision_file"
    fi

    exec "$exe_path" "$@"
  fi

  if [[ $# -lt 1 ]]; then
      fx-error Missing an explicit PRODUCT.BOARD goal.
      explain-goal-argument
      return 1
  fi

  cd "${FUCHSIA_DIR}"

  local gn_args=""
  case "$1" in
    *.*)
      local product_name="${1%.*}"
      local board_name="${1##*.}"
      local product board
      product="$(find_config "products" "${product_name}")"
      board="$(find_config "boards" "${board_name}")"
      if [[ "${product}" == "" ]] || [[ "${board}" == "" ]]; then
        exit 1
      fi
      gn_args+=" import(\"//${board}\") import(\"//${product}\")"
      gn_args+=" build_info_board=\"${board_name}\" build_info_product=\"${product_name}\""
      ;;
    *)
      fx-error "Unable to parse PRODUCT.BOARD goal \"$1\""
      explain-goal-argument
      return 1
      ;;
  esac
  shift

  local gn_cmd='gen'
  local -a gn_switches=(--fail-on-unused-args --check=system --export-rust-project --export-compile-commands=default --ninja-executable="${PREBUILT_NINJA}")
  local gn_after_args=""
  local base_packages=()
  local cache_packages=()
  local universe_packages=()
  local host_labels=()
  local auto_dir_variants=
  local auto_dir=false
  local is_release=false
  local build_dir=
  local variant=
  local use_goma
  local goma_dir
  local ensure_goma=1
  local cargo_toml_gen=0
  local ccache
  while [[ $# -ne 0 ]]; do
    case "$1" in
      --auto-dir)
        if [[ -n "${_FX_BUILD_DIR}" ]]; then
          fx-error "fx --dir and fx set --auto-dir are mutually exclusive, pick one."
          return 1
        fi
        auto_dir=true
        ;;
      --with-base)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        IFS="," read -r -a labels <<< "$2"
        base_packages+=("${labels[@]}")
        shift
        ;;
      --with-cache)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        IFS="," read -r -a labels <<< "$2"
        cache_packages+=("${labels[@]}")
        shift
        ;;
      --with)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        IFS="," read -r -a labels <<< "$2"
        universe_packages+=("${labels[@]}")
        shift
        ;;
      --with-host)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        IFS="," read -r -a labels <<< "$2"
        host_labels+=("${labels[@]}")
        shift
        ;;
      --cargo-toml-gen)
        cargo_toml_gen=1
        ;;
      --netboot)
        gn_after_args+=" enable_netboot=true"
        ;;
      --goma)
        use_goma=1
        ;;
      --no-goma)
        use_goma=0
        ;;
      --no-ensure-goma)
        ensure_goma=0
        ;;
      --goma-dir)
        # TODO(haowei): Remove it once no other script use it.
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        goma_dir=$2
        if [[ ! -d "${goma_dir}" ]]; then
          fx-error "GOMA directory does not exist: ${goma_dir}"
          return 1
        fi
        use_goma=1
        shift
        ;;
      --build-dir)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        if [[ -n "${_FX_BUILD_DIR}" ]]; then
          fx-error "fx --dir and fx set --build-dir are mutually exclusive, pick one."
          return 1
        fi
        fx-warn "DEPRECATED: \"fx set --build-dir DIR\""
        fx-warn "       NEW: \"fx --dir DIR set\""
        build_dir="$2"
        shift
        ;;
      --release)
        gn_args+=" is_debug=false"
        is_release=true
        ;;
      --variant)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        variant+="\"$2\","
        auto_dir_variants+="-$2"
        shift
        ;;
      --fuzz-with)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        variant+="{variant=\"$2-fuzzer\" target_type=[\"fuzzed_executable\"]},"
        # TODO(fxbug.dev/38226): Fuzzers need a version of libfdio.so that is sanitized,
        # but doesn't collect coverage data.
        variant+="{variant=\"$2\" label=[\"//sdk/lib/fdio\"]},"
        shift
        ;;
      --args)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        gn_args+=" $2"
        shift
        ;;
      --help-args)
        gn_cmd=args
        if [[ $# -ge 2 ]] && [[ "$2" != '--*' ]]; then
          gn_switches+=("--list=$2")
          shift
        else
          gn_switches+=(--list)
        fi
        fx-warn "DEPRECATED: \"fx set --help-args[=ARG]\""
        fx-warn "       NEW: \"fx args [--list=ARG]\""
        ;;
      --ccache)
        ccache=1
        ;;
      --no-ccache)
        ccache=0
        ;;
      --ide)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        gn_switches+=("--ide=$2")
        shift
        ;;
      --json-ide-script)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        gn_switches+=("--json-ide-script=$2")
        shift
        ;;
      *)
        fx-error "Unknown argument \"$1\""
        fx-command-help
        return 1
        ;;
    esac
    shift
  done

  if [[ -z "${build_dir}" ]]; then
    build_dir="${_FX_BUILD_DIR}"
  fi

  # Remove any trailing slash from build directory name.
  build_dir="${build_dir%/}"

  local config_build_dir
  if $auto_dir; then
    if [[ -n "$build_dir" ]]; then
      fx-error "--auto-dir and --build-dir are mutually exclusive, pick one."
      return 1
    fi
    if [[ "$auto_dir_variants" == */* ]]; then
      fx-error "--auto-dir only works with simple catch-all --variant switches; choose your own directory name with fx --dir for a complex configuration"
      return 1
    fi
    config_build_dir="out/${product_name}.${board_name}${auto_dir_variants}"
    if $is_release; then
      config_build_dir+="-release"
    fi
  else
    case "$build_dir" in
      '')
        # Default is "//out/default".  Store it as relative.
        config_build_dir="out/default"
        ;;
      //*|out/*)
        # GN-style "source-relative" path or relative out/something.
        config_build_dir="${build_dir#//}"
        ;;
      *)
        fx-error "Invalid build directory: ${build_dir}"
        fx-error "Please specify a build directory as \"out/something\"."
        exit 1
        ;;
    esac
  fi
  build_dir="${FUCHSIA_DIR}/${config_build_dir}"

  # Automatically detect goma and ccache if not specified explicitly.
  if [[ -z "${use_goma}" ]] && [[ -z "${ccache}" ]]; then
    # Use Goma if the user has authorized with the Goma service.
    if fx-command-run goma_auth info > /dev/null 2>&1; then
      use_goma=1
    elif [[ -n "${CCACHE_DIR}" ]] && [[ -d "${CCACHE_DIR}" ]]; then
      ccache=1
    fi
  elif [[ "${use_goma}" -eq 1 ]] && [[ "${ccache}" -eq 1 ]]; then
    fx-error "--goma and --ccache are mutually exclusive, pick one."
    return 1
  fi

  # Add goma or ccache settings as appropriate.
  if [[ "${use_goma}" -eq 1 ]]; then
    gn_args+=" use_goma=true"
  else
    gn_args+=" use_goma=false"
    if [[ "${ccache}" -eq 1 ]]; then
      gn_args+=" use_ccache=true"
    fi
  fi

  gn_args+="
# See: fx args --list=base_package_labels
base_package_labels+=["

  for package in "${base_packages[@]}"; do
    gn_args+="\"${package}\","
  done
  gn_args+="]

# See: fx args --list=cache_package_labels
cache_package_labels+=["

  for package in "${cache_packages[@]}"; do
    gn_args+="\"${package}\","
  done
  gn_args+="]

# See: fx args --list=universe_package_labels
universe_package_labels+=["

  for package in "${universe_packages[@]}"; do
    gn_args+="\"${package}\","
  done
  gn_args+="]

# See: fx args --list=host_labels
host_labels+=["

  for label in "${host_labels[@]}"; do
    gn_args+="\"${label}\","
  done
  gn_args+="]"

  if [[ -n "${variant}" ]]; then
    gn_args+=" select_variant=[${variant}]"
  fi

  if [[ "${cargo_toml_gen}" -eq 1 ]]; then
    gn_args+=" base_package_labels += [ \"//build/rust:cargo_toml_gen\" ]"
  fi

  gn_args+="${gn_after_args}"

  fx-gn ${gn_cmd} "${build_dir}" "${gn_switches[@]}" --args="${gn_args}" "$@"

  fx-change-build-dir "${config_build_dir}"

  if [[ "${use_goma}" -eq 1 ]] && [[ "${ensure_goma}" -eq 1 ]]; then
    fx-command-run goma || return $?
  fi
}

main "$@"