#!/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.

### Run Ninja to build Fuchsia

## usage: fx build [-SWITCH...] [zircon/TARGET | TARGET ...]
##
## This runs Ninja, usually twice: once for Zircon and once for Fuchsia.
## With no explicit targets, Zircon Ninja builds its default targets and
## then Fuchsia Ninja builds its default targets.
##
## For each `zircon/TARGET` argument, `TARGET` is passed to Zircon Ninja.
## For each other `TARGET` argument, `TARGET` is passed to Fuchsia Ninja.
## If all the target arguments are `zircon/TARGET`, Fuchsia Ninja is not run.
##
## Switch arguments are passed through to Ninja (same switches for both).
## Run `fx build -h` to see Ninja argument details.

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

function run-ninja {
  local continue_on_error=false
  for (( i=1; i<=$#; i++)); do
    j=$((i+1))
    if [ "${!i}" = "-k" ] && [ "${!j}" = "0" ]; then
      continue_on_error=true
    fi
  done
  # Use a subshell because fx-cmd-locked locks until exit, not function return.
  if [ "$continue_on_error" = false ]; then
    (fx-run-ninja "$PREBUILT_NINJA" "$@") || exit
  else
    local status
    (fx-run-ninja "$PREBUILT_NINJA" "$@")
    status=$?
    if [ "${status}" -ne 0 ]; then
      fx-warn "Build outputs may be inconsistent and may remain so; a clean build is recommended."
    fi
    return "${status}"
  fi
}

function main {
  local switches=() zircon_targets=() fuchsia_targets=()
  while [ $# -gt 0 ]; do
    case "$1" in
      # These Ninja switches take an argument.
      -[Cfjkldt])
        switches+=("$1" "$2")
        shift
        ;;
      -*)
        switches+=("$1")
        ;;
      zircon/*)
        zircon_targets+=("${1#zircon/}")
        ;;
      *)
        fuchsia_targets+=("$1")
        ;;
    esac
    shift
  done

  # A change to any of these might mean things are now done differently enough
  # that ninja's automatic re-gen rule might not be triggered or might not work
  # properly if it is triggered.  So preemptively force a re-gen if that seems
  # like a plausible possibility.
  local -r landmines=("$PREBUILT_GN"
                      "$FUCHSIA_DIR/tools/devshell/build"
                      "$FUCHSIA_DIR/tools/devshell/lib/vars.sh"
                     )
  local mine
  for mine in "${landmines[@]}"; do
    if [ "$mine" -nt "${ZIRCON_BUILDROOT}/build.ninja" -o \
         "$mine" -nt "${FUCHSIA_BUILD_DIR}/build.ninja" ]; then
      echo >&2 "Re-running gn gen first ($mine changed)"
      fx-gen || return
      break
    fi
  done

  if [ ! -d "$ZIRCON_BUILDROOT" ]; then
    echo >&2 "Re-running gn gen first (missing $ZIRCON_BUILDROOT)"
    fx-gen || return
  fi

  # Build requested Zircon targets.
  # Add default if building any Fuchsia targets.
  if [ ${#fuchsia_targets[@]} -ne 0 ]; then
    zircon_targets+=(default)
  fi
  local status
  run-ninja -C "${ZIRCON_BUILDROOT}" "${switches[@]}" "${zircon_targets[@]}"
  status=$?

  # If there were explicit Zircon targets and no other explicit targets,
  # the Zircon run was enough by itself.  Otherwise Zircon default is
  # a prerequisite for any Fuchsia target (including implicit default).
  if [ ${#fuchsia_targets[@]} -ne 0 -o ${#zircon_targets[@]} -eq 0 ]; then
    run-ninja -C "${FUCHSIA_BUILD_DIR}" "${switches[@]}" "${fuchsia_targets[@]}"
    fuchsia_status=$?
    if [ "${status}" -eq 0 ]; then
      status="${fuchsia_status}"
    fi
  fi

  return "${status}"
}

main "$@"