#!/bin/sh
set -eu

source_script=/tmp/wechat-local-ocr.py
source_bridge=/tmp/wechat-gui-bridge
source_recorder_unit=/tmp/wechat-local-ocr-recorder.service
source_responder_unit=/tmp/wechat-local-ocr-responder.service
source_defaults=/tmp/wechat-local-ocr.default
runtime_user=${JWEBOT_RUNTIME_USER:-jwebot}

target_script=/usr/local/sbin/wechat-local-ocr
target_bridge=/usr/local/sbin/wechat-gui-bridge
target_recorder_unit=/etc/systemd/system/wechat-local-ocr-recorder.service
target_responder_unit=/etc/systemd/system/wechat-local-ocr-responder.service
target_defaults=/etc/default/wechat-local-ocr
venv_python=${JWEBOT_RUNTIME_PYTHON:-/opt/jwebot/venv/bin/python}

timestamp=$(date +%Y%m%d-%H%M%S)
backup_dir="/root/wechat-local-ocr-backup-${timestamp}"
enable_legacy_ocr=${ENABLE_LEGACY_OCR:-0}
success=0
recorder_enabled=$(systemctl is-enabled wechat-local-ocr-recorder.service 2>/dev/null || true)
recorder_active=$(systemctl is-active wechat-local-ocr-recorder.service 2>/dev/null || true)
responder_enabled=$(systemctl is-enabled wechat-local-ocr-responder.service 2>/dev/null || true)
responder_active=$(systemctl is-active wechat-local-ocr-responder.service 2>/dev/null || true)

restore_file() {
    name=$1
    target=$2
    if [ -f "${backup_dir}/${name}" ]; then
        cp -a "${backup_dir}/${name}" "$target"
    else
        rm -f "$target"
    fi
}

restore_service_state() {
    systemctl disable --now \
        wechat-local-ocr-recorder.service \
        wechat-local-ocr-responder.service \
        >/dev/null 2>&1 || true
    case "$recorder_enabled" in
        enabled) systemctl enable wechat-local-ocr-recorder.service >/dev/null 2>&1 || true ;;
        masked) systemctl mask wechat-local-ocr-recorder.service >/dev/null 2>&1 || true ;;
    esac
    case "$responder_enabled" in
        enabled) systemctl enable wechat-local-ocr-responder.service >/dev/null 2>&1 || true ;;
        masked) systemctl mask wechat-local-ocr-responder.service >/dev/null 2>&1 || true ;;
    esac
    case "$recorder_active" in
        active|activating|reloading)
            systemctl start wechat-local-ocr-recorder.service >/dev/null 2>&1 || true
            ;;
    esac
    case "$responder_active" in
        active|activating|reloading)
            systemctl start wechat-local-ocr-responder.service >/dev/null 2>&1 || true
            ;;
    esac
}

rollback() {
    status=$?
    if [ "$success" -eq 0 ]; then
        systemctl disable --now wechat-local-ocr-recorder.service >/dev/null 2>&1 || true
        systemctl disable --now wechat-local-ocr-responder.service >/dev/null 2>&1 || true
        restore_file wechat-local-ocr "$target_script"
        restore_file wechat-gui-bridge "$target_bridge"
        restore_file wechat-local-ocr-recorder.service "$target_recorder_unit"
        restore_file wechat-local-ocr-responder.service "$target_responder_unit"
        restore_file wechat-local-ocr.default "$target_defaults"
        systemctl daemon-reload || true
        restore_service_state
    fi
    exit "$status"
}

trap rollback EXIT HUP INT TERM

test -x "$venv_python"
test -f "$source_script"
test -f "$source_bridge"
test -f "$source_recorder_unit"
test -f "$source_responder_unit"
test -f "$source_defaults"

install -d -o root -g root -m 0700 "$backup_dir"
for pair in \
    "wechat-local-ocr:$target_script" \
    "wechat-gui-bridge:$target_bridge" \
    "wechat-local-ocr-recorder.service:$target_recorder_unit" \
    "wechat-local-ocr-responder.service:$target_responder_unit" \
    "wechat-local-ocr.default:$target_defaults"
do
    name=${pair%%:*}
    target=${pair#*:}
    if [ -f "$target" ]; then
        cp -a "$target" "${backup_dir}/${name}"
    fi
done

rendered_recorder_unit="${backup_dir}/wechat-local-ocr-recorder.rendered.service"
rendered_responder_unit="${backup_dir}/wechat-local-ocr-responder.rendered.service"
sed \
    -e "s/^User=.*/User=$runtime_user/" \
    -e "s/^Group=.*/Group=$runtime_user/" \
    -e "s#/opt/jwebot/venv/bin/python#$venv_python#g" \
    "$source_recorder_unit" >"$rendered_recorder_unit"
sed \
    -e "s#/opt/jwebot/venv/bin/python#$venv_python#g" \
    "$source_responder_unit" >"$rendered_responder_unit"

install -o root -g root -m 0755 "$source_script" "$target_script"
install -o root -g root -m 0755 "$source_bridge" "$target_bridge"
install -o root -g root -m 0644 "$rendered_recorder_unit" "$target_recorder_unit"
install -o root -g root -m 0644 "$rendered_responder_unit" "$target_responder_unit"
install -o root -g root -m 0644 "$source_defaults" "$target_defaults"
install -d -o "$runtime_user" -g "$runtime_user" -m 0700 \
    /var/lib/wechat-local-ocr \
    /var/lib/wechat-local-ocr/history \
    /var/lib/wechat-local-ocr/queue \
    /var/lib/wechat-local-ocr/failed
chown -R "$runtime_user:$runtime_user" /var/lib/wechat-local-ocr
touch /var/lib/wechat-local-ocr/gui-interaction.lock
chown "$runtime_user:$runtime_user" /var/lib/wechat-local-ocr/gui-interaction.lock
chmod 0600 /var/lib/wechat-local-ocr/gui-interaction.lock

"$venv_python" -m py_compile "$target_script"
bash -n "$target_bridge"
systemd-analyze verify "$target_recorder_unit" "$target_responder_unit"
systemctl daemon-reload
systemctl disable --now \
    wechat-local-ocr-recorder.service \
    wechat-local-ocr-responder.service \
    >/dev/null 2>&1 || true
if [ "$enable_legacy_ocr" -eq 1 ]; then
    systemctl enable wechat-local-ocr-recorder.service
    systemctl start wechat-local-ocr-recorder.service
    systemctl is-active --quiet wechat-local-ocr-recorder.service
fi

success=1
trap - EXIT HUP INT TERM

echo "backup_dir=$backup_dir"
sha256sum "$target_script" "$target_bridge" "$target_recorder_unit" "$target_responder_unit" "$target_defaults"
if [ "$enable_legacy_ocr" -eq 1 ]; then
    systemctl status wechat-local-ocr-recorder.service --no-pager -l | sed -n '1,28p'
else
    echo "legacy_ocr=disabled"
fi