#!/bin/bash -e
#
# A script to update the checked-in jars corresponding to Java tools used
# by the Java rules in Bazel.
#
# For usage please run
# ~/third_party/java/java_tools/update_java_tools.sh help

# Maps the java tool names to their associated bazel target.
declare -A tool_name_to_target=(["JavaBuilder"]="src/java_tools/buildjar:JavaBuilder_deploy.jar" \
["VanillaJavaBuilder"]="src/java_tools/buildjar:VanillaJavaBuilder_deploy.jar" \
["GenClass"]="src/java_tools/buildjar/java/com/google/devtools/build/buildjar/genclass:GenClass_deploy.jar" \
["Runner"]="src/java_tools/junitrunner/java/com/google/testing/junit/runner:Runner_deploy.jar" \
["ExperimentalRunner"]="src/java_tools/junitrunner/java/com/google/testing/junit/runner:ExperimentalRunner_deploy.jar" \
["JacocoCoverage"]="src/java_tools/junitrunner/java/com/google/testing/coverage:JacocoCoverage_jarjar_deploy.jar" \
["Turbine"]="src/java_tools/buildjar/java/com/google/devtools/build/java/turbine/javac:turbine_deploy.jar" \
["TurbineDirect"]="src/java_tools/buildjar/java/com/google/devtools/build/java/turbine:turbine_direct_binary_deploy.jar" \
["SingleJar"]="src/java_tools/singlejar/java/com/google/devtools/build/singlejar:bazel-singlejar_deploy.jar"
["JarJar"]="third_party/jarjar:jarjar_command_deploy.jar")

usage="This script updates the checked-in jars corresponding to the tools "\
"used by the Java rules in Bazel.

To update all the tools simultaneously run from your bazel workspace root:
~/third_party/java/java_tools/update_java_tools.sh

To update only one or one subset of the tools run
third_party/java/java_tools/update_java_tools.sh tool_1 tool_2 ... tool_n

where tool_i can have one of the values: ${!tool_name_to_target[*]}.

For example, to update only JavaBuilder run
third_party/java/java_tools/update_java_tools.sh JavaBuilder

To update JavaBuilder, Turbine and SingleJar run
third_party/java/java_tools/update_java_tools.sh JavaBuilder Turbine SingleJar
"

if [[ ! -z "$1" && $1 = "help" ]]; then
  echo "$usage"
  exit
fi

# Stores the names of the tools required for update.
tools_to_update=()
if [[ ! -z "$@" ]]
then
   # Update only the tools specified on the command line.
   tools_to_update=("$@")
else
  # If no tools were specified update all of them.
  tools_to_update=(${!tool_name_to_target[*]})
fi

# Stores the workspace relative path of all the tools that were updated
# (e.g. third_party/java/java_tools/JavaBuilder_deploy.jar)
updated_tools=()

# Updates the tool with the given bazel target.
#
# Builds the given bazel target and copies the generated binary
# (which can be either under bazel-bin/ or bazel-genfiles/) under
# third_party/java/java_tools.
#
# Fails if the bazel build fails.
#
# bazel_target   The target to be built with bazel.
# tool_name      The name of the tool associated with the given bazel
#                target. Used only for printing error messages.
function update_tool() {
  local bazel_target="${1}"; shift
  local tool_name="${1}"; shift
  bazel build "$bazel_target" || (echo "Could not build $tool_name.
  Please see the Bazel error logs above." && exit 1)

  local binary=$(echo "bazel-bin/$bazel_target" | sed 's@:@/@')

  if [[ ! -f "$binary" ]]; then
    binary=$(echo "bazel-genfiles/$bazel_target" | sed 's@:@/@')
  fi

  local tool_basename=$(basename $binary)
  if [[ -f "$binary" ]]; then
    cp -f "$binary" "third_party/java/java_tools/$tool_basename"
    updated_tools+=("third_party/java/java_tools/$tool_basename")
  fi
}

# Updating the specified tools.
for tool in "${tools_to_update[@]}"
do
  # Get the bazel target associated with the current tool name.
  tool_bazel_target=${tool_name_to_target[$tool]}
  [[ -z "$tool_bazel_target" ]] && echo "Tool $tool is not supported.
  Please specify one or more of: ${!tool_name_to_target[*]}." && exit 1
  update_tool "$tool_bazel_target" "$tool"
done

if [[ ${#updated_tools[@]} -gt 0 ]]; then
  bazel_version=$(bazel version | grep "Build label" | cut -d " " -f 3)
  git_head=$(git rev-parse HEAD)
  echo ""
  echo "Please copy/paste the following into third_party/java/java_tools/README.md:"
  echo ""
  echo "The following tools were built with bazel $bazel_version at commit $git_head \
by running:
$ third_party/java/java_tools/update_java_tools.sh $@
"
  ( IFS=$'\n'; echo "${updated_tools[*]}" )
fi