#!/bin/sh
set -e

echo "=== Proto-Gen Go Toolchain ==="
echo "PROTO_REPO: ${PROTO_REPO}"
echo "PROTO_BRANCH: ${PROTO_BRANCH}"
echo "TARGET_REPO: ${TARGET_REPO}"

REPO_DIR=$(mktemp -d)
OUT_DIR=${OUT_DIR:-/out}
mkdir -p "${OUT_DIR}"

echo "--- Cloning proto repository ---"
git clone --branch "${PROTO_BRANCH}" --depth 1 \
    "https://${GIT_TOKEN}@${GIT_BASE_URL}/${PROTO_REPO}.git" "${REPO_DIR}/proto"

PROTO_SHA=$(cd "${REPO_DIR}/proto" && git rev-parse HEAD)
echo "Proto commit: ${PROTO_SHA}"

echo "--- Running protoc ---"
PROTO_FILES=$(find "${REPO_DIR}/proto" -name "*.proto" -type f)
for proto_file in ${PROTO_FILES}; do
    protoc \
        --proto_path="${REPO_DIR}/proto" \
        --go_out="${OUT_DIR}" --go_opt=paths=source_relative \
        --go-grpc_out="${OUT_DIR}" --go-grpc_opt=paths=source_relative \
        "${proto_file#${REPO_DIR}/proto/}"
done

echo "--- Cloning target repository ---"
TARGET_DIR=$(mktemp -d)
if git clone "https://${GIT_TOKEN}@${GIT_BASE_URL}/${TARGET_REPO}.git" "${TARGET_DIR}/target" 2>/dev/null; then
    echo "Target repo exists"
else
    echo "Creating target repository..."
    curl -s -X POST \
        -H "Authorization: token ${GIT_TOKEN}" \
        -H "Content-Type: application/json" \
        -d "{\"name\": \"${TARGET_REPO}\", \"auto_init\": false}" \
        "${GIT_BASE_URL}/api/v1/user/repos"
    git clone "https://${GIT_TOKEN}@${GIT_BASE_URL}/${TARGET_REPO}.git" "${TARGET_DIR}/target"
fi

echo "--- Checking for changes ---"
cd "${TARGET_DIR}/target"
cp -r "${OUT_DIR}"/* . 2>/dev/null || true
git add -A

if git diff --cached --quiet; then
    echo "No changes detected, idempotent exit"
    exit 0
fi

echo "--- Committing and pushing ---"
git config user.email "proto-gen@bot"
git config user.name "Proto-Gen Bot"
git commit -m "gen(go): from ${PROTO_REPO}@${PROTO_SHA}"
git push origin "${PROTO_BRANCH}"

echo "=== Done ==="