#!/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.

function find_tree_root {
  local parent="$1"
  if [[ ! -d "$parent" ]]; then
    return 1
  fi
  while [[ ! -d "${parent}/.jiri_root" ]]; do
    parent="$(dirname "${parent}")"
    if [[ "$parent" == "/" ]]; then
      return 1
    fi
  done
  echo "$parent"
}

# We walk the parent directories looking for .jiri_root rather than using
# BASH_SOURCE so that we find the fuchsia_dir enclosing the current working
# directory instead of the one containing this file in case the user has
# multiple source trees and is picking up this file from another one.
#
# NOTE: The FUCHSIA_DIR environment variable is ignored here because it
# could point to a different Fuchsia checkout in some developer setups.
#
# This logic is replicated in //scripts/fx, //scripts/hermetic_env,
# //scripts/zsh_completion/_fx, and //src/developer/ffx/scripts. For
# consistency, copy any changes here to those files as well.
if ! fuchsia_dir="$(find_tree_root "$(pwd)")"; then
  echo >&2 "ERROR: Cannot find the Platform Source Tree in a parent of the current directory: $(pwd)"
  exit 1
fi

script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"

if [[ "${script_dir}" != "${fuchsia_dir}"* ]]; then
  echo >&2 "ERROR: You are executing fx from outside of the current source tree"
  echo >&2 "ERROR: This is not supported as fx does not have a stable internal API"
  echo >&2
  echo >&2 "    'ffx' was executed from: ${BASH_SOURCE[0]}"
  echo >&2 "    'fuchsia directory' resolved to: ${fuchsia_dir}"
  echo >&2
  echo >&2 "To run a command in the current Fuchsia directory, run fx from:"
  echo >&2 "  ${fuchsia_dir}/scripts/fx ffx"
  exit 1
fi

exec "${fuchsia_dir}"/scripts/fx ffx "$@"