#!/bin/bash
# Copyright 2020 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=Internal API
### Builds and returns a list of a desired set of build artifacts

## usage: fx list-build-artifacts [--build] [--allow-empty | --expect-one] [FILTERS...] MODE
##
## Builds and returns a list of paths to special sets of build artifacts within
## the GN graph relative to the build directory.
##
##  --build       build the artifacts as well as returning a list of them
##  --allow-empty do not fail if no such artifacts are found
##  --expect-one  fail if zero or more than one artifacts are found. This
##                option is mutually exclusive from `--allow-empty`.
##  --name        filter the set of artifacts to pick out the particular one of
##                the same name
##  --os          filter the set of artifacts by intended operating system: one
##                of `fuchsia`, `linux`, or `mac`. Defaults to $HOST_OS when
##                the mode is `tools.`
##  --cpu         filter the set of artifacts by intended architecture: one of
##                `x64` or `arm64`. Defaults to $HOST_CPU when the mode is
##                `tools`.
##  --type         filter the set of artifacts by type.
##
##  MODE          One of the following:
##                `images` -- returns the list of images
##                `pave`-- returns the list of images needed to pave;
##                `pave-zedboot`-- returns the list of images needed to pave
##                zedboot;
##                `netboot`-- returns the list of images needed to netboot
##                `flash`-- returns the list of images needed to flash
##                `tools` -- returns the list of host tools
##                `zbi-tests`-- returns the list of ZBI tests
##                `generated-sources`-- returns the list of generated sources
###                (e.g., FIDL and Banjo bindings).
##

set -o errexit

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

readonly IMAGES_JSON="images.json"
readonly TOOL_PATHS_JSON="tool_paths.json"
readonly ZBI_TESTS_JSON="zbi_tests.json"
readonly GENERATED_SOURCES_JSON="generated_sources.json"

build=false
allow_empty=false
expect_one=false
mode=""
name=""
os=""
cpu=""
type=""
while [[ $# -ne 0 ]]; do
  case "$1" in
  --help|-h)
      fx-command-help
      exit 0
      ;;
  --build)
    build=true
    ;;
  --allow-empty)
    allow_empty=true
    ;;
  --expect-one)
    expect_one=true
    ;;
  --name)
    shift
    name="$1"
    ;;
  --os)
    shift
    os="$1"
    ;;
  --cpu)
    shift
    cpu="$1"
    ;;
  --type)
    shift
    type="$1"
    ;;
  -*)
    fx-error "Unknown flag: $1"
    fx-command-help
    exit 1
    ;;
  *)
    if [[ -z "${mode}" ]]; then
      mode="$1"
    else
      fx-error "unexpected argument: '$1'"
      exit 1
    fi
    ;;
  esac
  shift
done

if [[ -z "${mode}" ]]; then
  fx-error "MODE must be specified"
  fx-command-help
  exit 1
fi

if $allow_empty && $expect_one ; then
  fx-error "cannot set both --allow-empty and --expect-one"
  fx-command-help
  exit 1
fi

# Some build API modules are just plain JSON lists; in that case, we should
# not apply any filters.
is_list_like=false
manifest=""
jq_filter=".[]"
paths=()
if [[ "${mode}" == images ]]; then
  manifest="${IMAGES_JSON}"
elif [[ "${mode}" == pave ]]; then
  manifest="${IMAGES_JSON}"
  paths+=("pave.sh")
  jq_filter+=" | select(.bootserver_pave != null)"
elif [[ "${mode}" == pave-zedboot ]]; then
  manifest="${IMAGES_JSON}"
  paths+=("pave-zedboot.sh")
  jq_filter+=" | select(.bootserver_pave_zedboot != null)"
elif [[ "${mode}" == netboot ]]; then
  manifest="${IMAGES_JSON}"
  paths+=("netboot.sh")
  jq_filter+=" | select(.bootserver_netboot != null)"
elif [[ "${mode}" == flash ]]; then
  manifest="${IMAGES_JSON}"
  paths+=("flash.sh")
  jq_filter+=" | select(.fastboot_flash != null)"
elif [[ "${mode}" == tools ]]; then
  manifest="${TOOL_PATHS_JSON}"
  os="${os:-${HOST_OS}}"
  cpu="${cpu:-${HOST_CPU}}"
elif [[ "${mode}" == zbi-tests ]]; then
  manifest="${ZBI_TESTS_JSON}"
elif [[ "${mode}" == generated-sources ]]; then
  manifest="${GENERATED_SOURCES_JSON}"
  is_list_like=true
else
  fx-error "unknown MODE: ${mode}"
  fx-command-help
  exit 1
fi

if [[ ! -z "${name}" ]]; then
  jq_filter+=" | select(.name == \"${name}\")"
  # Filter existing paths by the name as well.
  if [[ "${paths[@]}" =~ "${name}" ]]; then
    paths=("${name}")
  else
    paths=()
  fi
fi

if ! $is_list_like ; then
  if [[ ! -z "${os}" ]]; then
    jq_filter+=" | select(.os == \"${os}\")"
  fi
  if [[ ! -z "${cpu}" ]]; then
    jq_filter+=" | select(.cpu == \"${cpu}\")"
  fi
  if [[ ! -z "${type}" ]]; then
    jq_filter+=" | select(.type == \"${type}\")"
  fi
  jq_filter+=" | .path"
fi

paths+=($(fx-command-run jq --raw-output "${jq_filter}" "${FUCHSIA_BUILD_DIR}/${manifest}"))
if $build && [[ ${#paths[@]} -ne 0 ]] ; then
  # For efficiency's sake, we avoid having to build zircon when building
  # host-side artifacts.
  if [[ ! -z "${os}" && "$os" != fuchsia ]]; then
    fx-command-run build --no-zircon "${paths[@]}" >&2
  else
    fx-command-run build "${paths[@]}" >&2
  fi
fi

if [[ ${#paths[@]} -eq 0 ]] && (! $allow_empty || $expect_one) ; then
  fx-error "found no artifacts in the GN graph of type \"${mode}\" with (name, os, cpu, type) == (\"${name:-*}\", \"${os:-*}\", \"${cpu:-*}\", \"${type:-*}\")"
  exit 1
fi

if [[ ${#paths[@]} -gt 1 ]] && $expect_one ; then
  fx-error "expected one artifact; found multiple: ${paths[@]}"
  exit 1
fi

echo "${paths[@]}"