#!/bin/bash
# Copyright 2017 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.

### set build configuration

## usage: fx set x86|x86-64|arm64|aarch64|gauss|hikey960|odroidc2
##               [--release] [--packages P1,P2,...]
##               [--build-dir DIR]
##               [--args ARG] [--help-args [ARG]] [--variant VARIANT]
##               [--goma|--no-goma] [--no-ensure-goma]
##               [--goma-dir DIR]
##               [--ccache|--no-ccache]
##
## x86 is accepted as an alias for x86-64.
## arm64 is accepted as an alias for aarch64.
##
## Sets build options.
##
## optional arguments:
##   --release             Build the release variant (e.g., more compiler
##                         optimizations, less debugging information).
##   --packages            Include the listed packages (separated by commas) in the
##                         system build. Defaults to the default set of packages
##                         for the current layer (e.g., "garnet/packages/default"
##                         for the Garnet layer). If the --package argument is
##                         given multiple times, all the specified packages are
##                         included in the build.
##   --variant             Pass --variant=VARIANT to gen.py, which itself is
##                         a shorthand for setting the `select_variant` GN
##                         build argument using a standard set of values.
##                         Multiple --variant arguments can be used.
##   --args                Additional argument to pass to gn. If the --args
##                         argument is given multiple times, all the specified
##                         arguments are passed to gn.
##   --help-args           Display GN arguments documentation.  If --help-args
##                         is followed by a GN build argument identifier, just
##                         that argument's documentation is displayed.
##                         If --help-args is used alone, all GN build arguments
##                         are displayed (lots of output).
##   --build-dir           The directory (relative to FUCHSIA_DIR) into which to
##                         generate the build system. Defaults to
##                         "out/<variant>-<arch>".
##   --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 is installed
##                         on your machine.
##   --no-ensure-goma      Skip ensuring that goma is started when using goma.
##   --goma-dir            The directory where goma is installed. Defaults to
##                         ~/goma.
##   --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.

source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"/lib/vars.sh

function main {
  if [[ $# -lt 1 ]]; then
    fx-command-help
    return 1
  fi

  local arch=
  local zircon_project=
  case $1 in
    x86 | x86-64)
      arch=x86-64
      zircon_project=x86
      ;;
    arm64 | aarch64)
      arch=aarch64
      zircon_project=arm64
      ;;
    gauss)
      arch=aarch64
      zircon_project=gauss
      ;;
    hikey960)
      arch=aarch64
      zircon_project=hikey960
      ;;
    odroidc2)
      arch=aarch64
      zircon_project=odroidc2
      ;;
    *)
      fx-command-help
      return 1
  esac

  local gen_args="${gen_args} --target_cpu ${arch} --platforms ${zircon_project}"
  shift

  local variant=debug
  local packages=
  local build_dir=
  local use_goma
  local goma_dir
  local ensure_goma=1
  local ccache
  while [[ $# -ne 0 ]]; do
    case $1 in
      --release)
        gen_args="${gen_args} --release"
        variant=release
        ;;
      --packages)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        if [[ -z "${packages}" ]]; then
          packages="$2"
        else
          packages="${packages},$2"
        fi
        shift
        ;;
      --build-dir)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        build_dir="$2"
        shift
        ;;
      --goma)
        use_goma=1
        ;;
      --no-goma)
        use_goma=0
        ;;
      --no-ensure-goma)
        ensure_goma=0
        ;;
      --goma-dir)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        goma_dir=$2
        if [[ ! -d "${goma_dir}" ]]; then
          echo -e "error: GOMA directory does not exist: "${goma_dir}""
          return 1
        fi
        shift
        ;;
      --variant)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        gen_args="${gen_args} --variant $2"
        shift
        ;;
      --args)
        if [[ $# -lt 2 ]]; then
          fx-command-help
          return 1
        fi
        gen_args="${gen_args} --args $2"
        shift
        ;;
      --help-args)
        gen_args="${gen_args} --help-args"
        if [[ $# -ge 2 ]] && [[ "$2" != '--*' ]]; then
          gen_args="${gen_args} $2"
          shift
        fi
        ;;
      --ccache)
        ccache=1
        ;;
      --no-ccache)
        ccache=0
        ;;
      *)
        fx-command-help
        return 1
    esac
    shift
  done

  if [[ -n "${packages}" ]]; then
    gen_args="${gen_args} --packages ${packages}"
  else
    local -r jiri_manifest="${FUCHSIA_DIR}/.jiri_manifest"

    # TODO(pylaligand): remove this check once the Fuchsia population has moved
    # away from that specific manifest.
    if grep -q "\"fuchsia\"" "${jiri_manifest}"; then
      echo -e "error: You are using the obsolete 'fuchsia' manifest."
      echo -e "error: Please switch to the Topaz manifest instead: fx set-layer topaz"
      return 1
    fi

    # TODO(abarth): We might want to make this logic more sophisticated once we
    # have a mechanism for switching between layers or for selecting which
    # layers to build from source.

    # If multiple cases below trigger, gen.py will error out because gen.py
    # doesn't support multiple --packages arguments. However, we shouldn't get
    # into this situation because jiri would have already errored out due to the
    # conflicting version requirements of importing 2+ layers at the same time.

    if grep -q "manifest/garnet" "${jiri_manifest}"; then
      gen_args="${gen_args} --packages garnet/packages/default"
    fi

    if grep -q "manifest/peridot" "${jiri_manifest}"; then
      gen_args="${gen_args} --packages peridot/packages/default"
    fi

    if grep -q "manifest/topaz" "${jiri_manifest}"; then
      gen_args="${gen_args} --packages topaz/packages/default"
    fi

    if [[ `cat ${jiri_manifest}` =~ vendor/([a-zA-Z0-9_-]+) ]]; then
      local -r name="${BASH_REMATCH[1]}"
      gen_args="${gen_args} --packages vendor/${name}/packages/default"
    fi
  fi

  if [[ -n "${build_dir}" ]]; then
    gen_args="${gen_args} --build-dir ${build_dir}"
  else
    # gen.py defaults to determining the build directory from the variant and
    # the arch. We replicate that logic here rather than passing a redundant
    # argument to gen.py.
    build_dir="out/${variant}-${arch}"
  fi

  # If a goma directory wasn't specified explicitly then default to "~/goma".
  if [[ -z "${goma_dir}" ]]; then
    goma_dir="$HOME/goma"
  fi

  # Automatically detect goma and ccache if not specified explicitly.
  if [[ -z "${use_goma}" ]] && [[ -z "${ccache}" ]]; then
    if [[ -d "${goma_dir}" ]]; then
      use_goma=1
    elif [[ -n "${CCACHE_DIR}" ]] && [[ -d "${CCACHE_DIR}" ]]; then
      ccache=1
    fi
  fi

  # Add --goma or --ccache as appropriate.
  if [[ "${use_goma}" -eq 1 ]]; then
    gen_args="${gen_args} --goma ${goma_dir}"
  elif [[ "${ccache}" -eq 1 ]]; then
    gen_args="${gen_args} --ccache"
  fi

  # Update print-vars if you add or remove anything from this list.
  cat >"${FUCHSIA_CONFIG}" <<END
# Generated by "fx set".
FUCHSIA_BUILD_DIR="${build_dir}"
FUCHSIA_VARIANT="${variant}"
FUCHSIA_ARCH="${arch}"
ZIRCON_PROJECT="${zircon_project}"
END
  "${FUCHSIA_DIR}/build/gn/gen.py" ${gen_args} "$@"

  if [[ "${use_goma}" -eq 1 ]] && [[ "${ensure_goma}" -eq 1 ]]; then
    if ! [[ $("${goma_dir}/gomacc" port) =~ ^[0-9]+$ ]]; then
      "${goma_dir}/goma_ctl.py" ensure_start || return $?
    fi
  fi
}

main "$@"