#!/bin/bash

#  Copyright The ANGLE Project Authors. All rights reserved.
#  Use of this source code is governed by a BSD-style license that can be
#  found in the LICENSE file.
#
# Generates a roll CL within the ANGLE repository of AOSP.
#
# WARNING: Running this script without args may mess up the checkout.
#   See --genAndroidBp for testing just the code generation.

# exit when any command fails
set -eE -o functrace

failure() {
  local lineno=$1
  local msg=$2
  echo "Failed at $lineno: $msg"
}
trap 'failure ${LINENO} "$BASH_COMMAND"' ERR

# Change the working directory to the ANGLE root directory
cd "${0%/*}/.."

GN_OUTPUT_DIRECTORY=out/Android

function generate_Android_bp_file() {
    abis=(
        "arm"
        "arm64"
        "x86"
        "x64"
    )

    for abi in "${abis[@]}"; do
        # generate gn build files and convert them to blueprints
        gn_args=(
            "target_os = \"android\""
            "is_component_build = false"
            "is_debug = false"
            "dcheck_always_on = false"
            "symbol_level = 0"
            "angle_standalone = false"
            "angle_build_all = false"

            # Build for 64-bit CPUs
            "target_cpu = \"$abi\""

            # Target ndk API 26 to make sure ANGLE can use the Vulkan backend on Android
            "android_ndk_api_level = 26"

            # Disable all backends except Vulkan
            "angle_enable_vulkan = true"
            "angle_enable_gl = false"
            "angle_enable_d3d11 = false"
            "angle_enable_null = false"
            "angle_enable_metal = false"
            "angle_enable_wgpu = false"

            # SwiftShader is loaded as the system Vulkan driver on Android, not compiled by ANGLE
            "angle_enable_swiftshader = false"

            # Disable all shader translator targets except desktop GL (for Vulkan)
            "angle_enable_essl = false"
            "angle_enable_glsl = false"
            "angle_enable_hlsl = false"

            "angle_enable_commit_id = false"

            # Disable histogram/protobuf support
            "angle_has_histograms = false"

            # Use system lib(std)c++, since the Chromium library breaks std::string
            "use_custom_libcxx = false"

            # Test the system EGL loader
            "angle_test_enable_system_egl = true"
            "build_angle_end2end_tests_library = true"
            "build_angle_trace_tests = false"

            # Disable Perfetto
            "angle_enable_perfetto = false"

            # This has no effect in Android.bp file, but is listed here to make the point.
            # The actual flags are added in generate_android_bp.py file.
            # Enable link time optimization.
            #"use_thin_lto = true"
            #"thin_lto_enable_optimizations = true"

            # Uncomment when we are ready to test IR in Android
            # "angle_ir = true"
        )

        if [[ "$ENABLE_API_TRACE" == "true" ]]; then
            gn_args=(
                "${gn_args[@]}"
                "angle_enable_trace = true"
                "angle_enable_trace_android_logcat = true"
            )
        fi

        # This has no effect in Android.bp file, but is listed here to make the point.
        # The actual flags are added in generate_android_bp.py file.
        # Disable CFI.
        #if [[ "$abi" == "arm64" ]]; then
        #    gn_args=(
        #        "${gn_args[@]}"
        #        "arm_control_flow_integrity = \"none\""
        #    )
        #fi

        gn gen ${GN_OUTPUT_DIRECTORY} --args="${gn_args[*]}"
        gn desc ${GN_OUTPUT_DIRECTORY} --format=json "*" > ${GN_OUTPUT_DIRECTORY}/desc.$abi.json
    done

    vpython3 scripts/generate_android_bp.py \
        --gn_json_arm=${GN_OUTPUT_DIRECTORY}/desc.arm.json \
        --gn_json_arm64=${GN_OUTPUT_DIRECTORY}/desc.arm64.json \
        --gn_json_x86=${GN_OUTPUT_DIRECTORY}/desc.x86.json \
        --gn_json_x64=${GN_OUTPUT_DIRECTORY}/desc.x64.json \
        --output=Android.bp
}

function generate_angle_commit_file() {
    # Output chromium ANGLE git hash during ANGLE to Android roll into
    # {AndroidANGLERoot}/angle_commit.h.
    # In Android repos, we stop generating the angle_commit.h at compile time,
    # because in Android repos, access to .git is not guaranteed, running
    # commit_id.py at compile time will generate "unknown hash" for ANGLE_COMMIT_HASH.
    # Instead, we generate angle_commit.h during ANGLE to Android roll time.
    # Before roll_aosp.sh is called during the roll, ANGLE_UPSTREAM_HASH environment
    # variable is set to {rolling_to} git hash, and that can be used by below
    # script commit_id.py as the ANGLE_COMMIT_HASH written to the angle_commit.h.
    # See b/348044346.
    vpython3 src/commit_id.py \
        gen \
        angle_commit.h
}

function print_help() {
    echo "Usage: roll_aosp.sh [options]

Generate Android.bp for compiling current ANGLE code in Android repo

Options:
  -h, --help                 Show this help message and exit
  --genAndroidBp             Only test Android.bp generation without rolling deps. This should only be done in upstream chromium ANGLE checkout for testing purposes
  --enableApiTrace           Enable API tracing in the generated Android.bp
  --cleanGitSubmodules=true|false Clean up git submodules at the end (default to true when inside Android repo)

It is allowed to pass multiple options to the script, for example:
  roll_aosp.sh --enableApiTrace --cleanGitSubmodules=true"
}

# Check if we are inside an Android repo
is_in_android_repo() {
    if [[ -n "$ANDROID_BUILD_TOP" && -d "$ANDROID_BUILD_TOP/.repo" ]]; then
        return 0
    fi
    if [[ -d "../../.repo" ]]; then
        return 0
    fi
    return 1
}

# throw an error if ANGLE_UPSTREAM_HASH is not set (b/348044346)
if [[ -z "${ANGLE_UPSTREAM_HASH}" ]]; then
    echo "ANGLE_UPSTREAM_HASH environment variable is not set. Please run command 'export ANGLE_UPSTREAM_HASH=\"{git_hash}\"' before running roll_aosp.sh.
{git_hash} should be the git hash of the most recent ANGLE commit in upstream that current repo has already rolled in."
    exit 1
fi

CLEAN_GIT_SUBMODULES=false
if is_in_android_repo; then
    CLEAN_GIT_SUBMODULES=true
fi

CLEAN_GIT_SUBMODULES_EXPLICITLY_SET=false
GEN_ANDROID_BP=false
ENABLE_API_TRACE=false

if [[ $# -eq 1 && ( "$1" == "-h" || "$1" == "--help" ) ]]; then
    print_help
    exit 0
fi

for arg in "$@"; do
    case "$arg" in
        --cleanGitSubmodules)
            if [[ "$CLEAN_GIT_SUBMODULES_EXPLICITLY_SET" == "true" ]]; then
                echo "Error: --cleanGitSubmodules specified more than once."
                exit 1
            fi
            echo "Error: --cleanGitSubmodules requires a value (e.g. --cleanGitSubmodules=true or --cleanGitSubmodules=false)"
            echo ""
            print_help
            exit 1
            ;;
        --cleanGitSubmodules=*)
            if [[ "$CLEAN_GIT_SUBMODULES_EXPLICITLY_SET" == "true" ]]; then
                echo "Error: --cleanGitSubmodules specified more than once."
                exit 1
            fi
            CLEAN_GIT_SUBMODULES_EXPLICITLY_SET=true
            val="${arg#*=}"
            if [[ "$val" == "true" ]]; then
                CLEAN_GIT_SUBMODULES=true
            elif [[ "$val" == "false" ]]; then
                CLEAN_GIT_SUBMODULES=false
            else
                echo "Error: Invalid value '$val' for --cleanGitSubmodules. Must be true or false."
                echo ""
                print_help
                exit 1
            fi
            ;;
        --genAndroidBp)
            GEN_ANDROID_BP=true
            ;;
        --enableApiTrace)
            ENABLE_API_TRACE=true
            ;;
        -h|--help)
            print_help
            ;;
        *)
            echo "Error: Unknown option '$arg'"
            echo ""
            print_help
            exit 1
            ;;
    esac
done


if [[ "$GEN_ANDROID_BP" == "true" ]]; then
    generate_Android_bp_file
    exit 0
fi

# Check out depot_tools locally and add it to the path
DEPOT_TOOLS_DIR=_depot_tools
rm -rf ${DEPOT_TOOLS_DIR}
git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git ${DEPOT_TOOLS_DIR}
export PATH=`pwd`/${DEPOT_TOOLS_DIR}:$PATH


# This script is executed by the Skia roller in *AOSP* checkout (with new ANGLE changes merged into it by git merge).
# The Skia roller merges ANGLE changes and also has code to remove submodules and extra files.
# For local setup including the additional Skia roller actions see go/angle-skia-roller-local
#
# Some caveats due to the way this is set up:
# * If a file is deleted from AOSP by a previous commit to AOSP *and* is changed upstream in ANGLE,
#   git merge will fail in Skia roller before even reaching this script. This sometimes happens with e.g. .gitmodules
#
# * If a file is needed to run gn gen (commonly BUILD.gn) it might need to take a different path:
#
#   * If this file comes from ANGLE, it is already git-merged into AOSP by Skia roller by the time we get to this script
#      - example: ANGLE source files, but also e.g. third_party/jdk/BUILD.gn (see note below)
#
#   * If this file comes from a third_party dep (pulled by gclient in generate_Android_bp_file), it is either:
#      1. deleted after the codegen ensuring it is *not* in AOSP (delete_after_codegen_paths)
#      2. automatically ignored due to it being part of a sub-repo not this repo (.git subdirs in git deps but not cipd)
#      3. copied to AOSP intentionally by this script (copy_to_aosp_paths, which deletes .git subdirs to avoid the case 2)
#      4. copied to AOSP implicitly, without being in copy_to_aosp_paths:
#         - dep does not have a .git subdir (dep_type cipd in DEPS)
#         - not listed in delete_after_codegen_paths
#         - example: files under third_party/r8
#
#   Note: a file being under third_party/ does *not* necessarily imply it comes from a dep. For example third_party/jdk/BUILD.gn
#         comes from the ANGLE repo, not from the upstream Chromium third_pary/jdk repo.. but it can be different in other cases.
#         In cases like third_party/jdk/BUILD.gn, we need to make sure it is *not* part of delete_after_codegen_paths as
#         this script would delete this file from AOSP after one roll and the next roll would fail gn gen.

# Deps copied to AOSP by having .git removed from them then git add (via git_add_paths)
# .git removed so that it's not an "embedded repository" https://gist.github.com/claraj/e5563befe6c2fb108ad0efb6de47f265
copy_to_aosp_paths=(
    "build"
    "third_party/abseil-cpp"
    "third_party/glslang/src"
    "third_party/re2/src"
    "third_party/rapidjson/src"
    "third_party/spirv-headers/src"
    "third_party/spirv-tools/src"
    "third_party/vulkan-headers/src"
    "third_party/vulkan_memory_allocator"
)

# Dirs and files deleted after codegen so that they don't get added to AOSP.
# We don't need this for dirs with .git in them as those are already ignored by git.
delete_after_codegen_paths=(
   "third_party/android_build_tools"
   "third_party/android_sdk"
   "third_party/android_system_sdk"
   "third_party/android_toolchain"
   "third_party/clspv/gn"
   "third_party/colorama"
   "third_party/jdk/current"  # subdirs only to keep third_party/jdk/BUILD.gn (not pulled by gclient as it comes from ANGLE repo)
   "third_party/llvm-build"
   "third_party/r8"
   "third_party/rust"
   "third_party/rust-toolchain"
   "third_party/turbine"
   "third_party/zlib"  # Replaced by Android's zlib

   # build/linux is hundreds of megs that aren't needed.
   "build/linux"
   # Debuggable APKs cannot be merged into AOSP as a prebuilt
   "build/android/CheckInstallApk-debug.apk"
   # Remove Android.mk files to prevent automated CLs:
   #   "[LSC] Add LOCAL_LICENSE_KINDS to external/angle"
   "Android.mk"
   "third_party/glslang/src/Android.mk"
   "third_party/glslang/src/ndk_test/Android.mk"
   "third_party/spirv-tools/src/Android.mk"
   "third_party/spirv-tools/src/android_test/Android.mk"
   "third_party/siso" # Not needed
)

# Dirs added to the commit with `git add -f`. Applies to both copy_to_aosp_paths and delete_after_codegen_paths.
git_add_paths=(
  "build"
  "third_party"
)


# Delete first to get a clean checkout by gclient
for path in "${copy_to_aosp_paths[@]}"; do
    rm -rf "$path"
done

# Remove cruft from any previous bad rolls (https://anglebug.com/42266781)
find third_party -wholename "*/_gclient_*" -delete

# Workaround to avoid gclient errors https://crbug.com/skia/14155#c3
rm -rf "third_party/zlib"

# Sync all of ANGLE's deps so that 'gn gen' works
vpython3 scripts/bootstrap.py
gclient sync --reset --force --delete_unversioned_trees

# Delete outdir to ensure a clean gn run.
rm -rf ${GN_OUTPUT_DIRECTORY}

generate_Android_bp_file
git add Android.bp

generate_angle_commit_file
git add angle_commit.h

# Delete outdir to cleanup after gn.
rm -rf ${GN_OUTPUT_DIRECTORY}

# Delete files that we do not want in AOSP.
# Some of them are needed for codegen so this happens after generate_Android_bp_file.
for path in "${delete_after_codegen_paths[@]}"; do
   rm -rf "$path"
done

# Delete the .git files in each dep so that it can be copied to this repo. Some deps like jsoncpp
# have multiple layers of deps so delete everything before adding them.
for dep in "${copy_to_aosp_paths[@]}"; do
   git rm -rf --cached --ignore-unmatch "$dep"
   rm -rf "$dep"/.git
done

# Delete all the .gitmodules files, since they are not allowed in AOSP external projects.
find . -name \.gitmodules -exec rm {} \;

# Add all changes under git_add_paths to sync changes (including deletion) in those dirs to AOSP.
for path in "${git_add_paths[@]}"; do
    git add -f $path
done

# Done with depot_tools
rm -rf $DEPOT_TOOLS_DIR

# Clean git submodules
# This should only be performed when roll_aosp.sh is ran in
# android_repo/external/angle.
if [[ "$CLEAN_GIT_SUBMODULES" == "true" ]]; then
    # delete submodules
    # first save the submodules dir to a list
    files=$(git ls-files -s | awk '/^160000/ { print $4; }')
    for f in $files
    do
        # remove the submodules from git:
        git rm -f --cached $f
        # remove the submodules from disk:
        echo "remove $f from disk"
        rm -rf $f
    done
fi