#!/bin/bash
#
# Copyright (C) 2022-2023 The LeafOS 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.
#

usage() {
    echo "Usage ${0} <branch>"
}

# Verify argument count
if [ "$#" -ne 1 ]; then
    usage
    exit 1
fi

BRANCH="${1}"

# Check to make sure this is being run from the top level repo dir
if [ ! -e "build/envsetup.sh" ]; then
    echo "Must be run from the top level repo dir"
    exit 1
fi

# Source build environment (needed for gettop)
. build/envsetup.sh

TOP="$(gettop)"
MERGEDREPOS="${TOP}/merged_repos_lineage.txt"
MANIFEST="${TOP}/.repo/manifests/snippets/leaf.xml"
LEAF_BRANCH=$(git -C ${TOP}/.repo/manifests.git config --get branch.default.merge | sed 's#refs/heads/##g')

# Build list of LeafOS forked repos
PROJECTPATHS=$(repo forall -g lineage -c 'echo -n "$REPO_PATH "')

echo "#### LineageOS branch = ${BRANCH} Branch = ${LEAF_BRANCH} ####"

# Make sure manifest and forked repos are in a consistent state
echo "#### Verifying there are no uncommitted changes on LeafOS forked LineageOS projects ####"
for PROJECTPATH in ${PROJECTPATHS} .repo/manifests; do
    # Skip fully removed projects
    [ ! -d "${TOP}/$PROJECTPATH" ] && continue;
    cd "${TOP}/${PROJECTPATH}"
    if [[ -n "$(git status --porcelain)" ]]; then
        echo "Path ${PROJECTPATH} has uncommitted changes. Please fix."
        exit 1
    fi
done
echo "#### Verification complete - no uncommitted changes found ####"

# Remove any existing list of merged repos file
rm -f "${MERGEDREPOS}"

# Iterate over each forked project
for PROJECTPATH in ${PROJECTPATHS}; do
    REPO=android_$(echo $PROJECTPATH | sed 's|/|_|g')
    REPOBRANCH="${BRANCH}"
    LOCAL_BRANCH="${LEAF_BRANCH}"

    # Override repo name / branch for qcom projects
    REPO_OVERRIDE=$(grep -Pio "<project path=\"${PROJECTPATH}\".*name=\"LeafOS-Project/\K[^\"]*" "${MANIFEST}")
    BRANCH_OVERRIDE=$(grep -Pio "<project path=\"${PROJECTPATH}\".*revision=\"\K[^\"]*" "${MANIFEST}")
    [ ! -z "${REPO_OVERRIDE}" ] && REPO="${REPO_OVERRIDE}"
    if [ ! -z "${BRANCH_OVERRIDE}" ]; then
        # Branch override is expected to start with default branch as prefix
        # e.g. leaf-2.0-legacy-um
        REPOBRANCH=$(echo "${BRANCH_OVERRIDE}" | sed "s|^${LEAF_BRANCH}|${BRANCH}|g")
        LOCAL_BRANCH="${BRANCH_OVERRIDE}"
    fi

    cd "${TOP}/${PROJECTPATH}"
    echo "### Merging ${REPOBRANCH} into ${PROJECTPATH} ###"
    git fetch https://github.com/LineageOS/"${REPO}" "${REPOBRANCH}"

    # Was there any change upstream? Skip if not.
    if [[ -z "$(git log --oneline HEAD..FETCH_HEAD)" ]]; then
        echo -e "nochange\t\t${PROJECTPATH}" | tee -a "${MERGEDREPOS}"
        continue
    fi

    git merge FETCH_HEAD --into-name "${LOCAL_BRANCH}"

    CONFLICT=""
    if [[ -n "$(git status --porcelain)" ]]; then
        CONFLICT="conflict-"
    fi
    echo -e "${CONFLICT}merge\t\t${PROJECTPATH}" | tee -a "${MERGEDREPOS}"
done