#!/bin/bash
# Copyright (C) 2024 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

set -e

SCRIPT_NAME="${0##*/}"

usage() {
    cat <<"EOF"

$SCRIPT_NAME: Shrink / unshrink SystemUiRavenTests.

    SystemUiRavenTests has a lot of kotlin source files, so it's slow to build,
    which is painful when you want to run it after updating ravenwood code
    that SystemUiRavenTests depends on. (example: junit-src/)

    This script basically removes the test files in SystemUI/multivalentTests
    that don't have @EnabledOnRavenwood. But if we actaully remove them,
    soong would re-generate the ninja file, which will take a long time,
    so instead it'll truncate them.

    This script will also tell git to ignore these files, so they won't shw up
    in `git status`.
    (Use `git ls-files -v | sed -ne "s/^[a-zS] //p"` to show ignored filse.)

Usage:
    $SCRIPT_NAME -s # Shrink the test files.

    $SCRIPT_NAME -u # Undo it.

EOF
}

TEST_PATH=${ANDROID_BUILD_TOP}/frameworks/base/packages/SystemUI/multivalentTests
cd "$TEST_PATH"

command=""
case "$1" in
    "-s") command=shrink ;;
    "-u") command=unshrink ;;
    *) usage ; exit 1 ;;
esac


echo "Listing test files...."
files=( $(find . -name '*Test.kt' -o -name '*Test.java') )

exemption='(BaseHeadsUpManagerTest)'

shrink() {
    local target=()
    for file in ${files[@]}; do
        # Check for exemption
        if echo $file | egrep -q "$exemption"; then
            echo "  Skip exempted file"
            continue
        fi

        echo "Checking $file"
        if ! [[ -f $file ]] ; then
            echo "  Skip non regular file"
            continue
        fi

        if ! [[ -s $file ]] ; then
            echo "  Skip empty file"
            continue
        fi

        if grep -q '@EnabledOnRavenwood' $file ; then
            echo "  Skip ravenwood test file".
            continue
        fi

        # It's a non ravenwood test file. Empty it.
        : > $file

        # Tell git to ignore the file

        target+=($file)

        echo "  Emptied"

    done
    if (( ${#target[@]} == 0 )) ; then
        echo "No files emptied."
        return 0
    fi

    git update-index --skip-worktree ${target[@]}

    echo "Emptied ${#target[@]} files"
    return 0
}

unshrink() {
    local target=()

    # Collect empty files
    for file in ${files[@]}; do
        if [[ -s $file ]] ; then
            continue
        fi

        target+=($file)
        : > $file
    done
    if (( ${#target[@]} == 0 )) ; then
        echo "No files to restore."
        return 0
    fi
    # Un-ignore the files, and check out the original files
    echo "Restoring ${#target[@]} files..."
    git update-index --no-skip-worktree ${target[@]}
    git checkout goog/main ${target[@]}
    return 0
}

$command