#!/usr/bin/env bash
set -euo pipefail
session_target_started=0
shell_pid=
agent_pid=
autostart_pid=
rime_unit=
manage_session=0
if [[ ${FERESE_SESSION_MODE:-desktop} == desktop && ${FERESE_SESSION_IMPORT_ENV:-0} == 1 ]]; then
    manage_session=1
fi
cleanup() {
    trap - EXIT INT TERM
    if [[ -n $autostart_pid ]]; then
        kill "$autostart_pid" 2>/dev/null || true
        wait "$autostart_pid" 2>/dev/null || true
    fi
    if [[ -n $shell_pid ]]; then kill "$shell_pid" 2>/dev/null || true; fi
    if [[ -n $agent_pid ]]; then
        kill "$agent_pid" 2>/dev/null || true
        wait "$agent_pid" 2>/dev/null || true
    fi
    if [[ -n $rime_unit ]]; then
        timeout --kill-after=1s 6s systemctl --user stop "$rime_unit" || true
    fi
    if ((session_target_started)); then
        systemctl --user stop ferese-session.target || true
    fi
}
trap cleanup EXIT
trap 'exit 130' INT
trap 'exit 143' TERM

# The compositor supplies its new Wayland socket before this helper starts.
# Nested previews must never replace the host session's activation environment.
if ((manage_session)); then
    # Shell control uses a private socket FD. Activation must use the public
    # socket so portal and other desktop services connect as ordinary clients.
    public_display=${FERESE_PUBLIC_WAYLAND_DISPLAY:-${WAYLAND_DISPLAY:-}}
    # Empty assignments replace stale values; D-Bus cannot remove activation variables.
    activation_vars=(
        "WAYLAND_DISPLAY=$public_display"
        "DISPLAY=${DISPLAY:-}"
        "XAUTHORITY=${XAUTHORITY:-}"
        "FERESE_SOCKET=${FERESE_SOCKET:-}"
        XDG_CURRENT_DESKTOP
        XDG_SESSION_DESKTOP
        XDG_SESSION_TYPE
    )
    if [[ ${FERESE_ENABLE_INPUT_METHOD:-0} == 1 ]]; then
        activation_vars+=("GTK_IM_MODULE=" QT_IM_MODULE QT_IM_MODULES IBUS_ADDRESS FERESE_RIME_CONTROL
                          "SDL_IM_MODULE=" "XMODIFIERS=${XMODIFIERS:-}")
    fi
    if command -v dbus-update-activation-environment >/dev/null; then
        if ! env WAYLAND_DISPLAY="$public_display" \
            dbus-update-activation-environment --systemd "${activation_vars[@]}"; then
            env WAYLAND_DISPLAY="$public_display" \
                dbus-update-activation-environment "${activation_vars[@]}" || true
        fi
    fi
    # User buses can outlive logout and may predate a newly installed service directory.
    if command -v dbus-send >/dev/null; then
        dbus-send --session --type=method_call --print-reply \
            --dest=org.freedesktop.DBus /org/freedesktop/DBus \
            org.freedesktop.DBus.ReloadConfig >/dev/null || true
    fi
    if command -v systemctl >/dev/null; then
        systemctl --user daemon-reload || true
        if systemctl --user start ferese-session.target; then
            session_target_started=1
            # A user manager can retain the target across session transitions.
            # Refresh an already-running portal after importing this session's
            # environment so it uses the installed release and current display.
            systemctl --user try-restart xdg-desktop-portal-ferese.service || true
        else
            echo 'Ferese: graphical session target could not start; portal activation may be unavailable.' >&2
        fi
    fi
fi
release_dir=$(dirname -- "$(readlink -f -- "$0")")
# Start the native input method on the public socket, without shell privileges.
# Pin the executable to this release and let systemd recover both crashes and a
# stalled input loop. A failed IME must leave the compositor and shell usable.
start_rime() {
    local user_data=${FERESE_RIME_USER_DATA:-${XDG_DATA_HOME:-$HOME/.local/share}/ferese/rime}
    local shared_data=${FERESE_RIME_SHARED_DATA:-/usr/share/rime-data}
    local identity=${FERESE_SOCKET:-${XDG_RUNTIME_DIR:-}/$public_display}
    local name variable load_state deadline
    local -a environment=()
    name=$(systemd-escape --template=ferese-rime-session@.service "$identity") || return 1
    [[ -x $release_dir/ferese-rime ]] || return 1
    [[ -r $shared_data/luna_pinyin_simp.schema.yaml ]] || {
        echo 'Ferese: install the Rime Luna Pinyin schemas before starting native input.' >&2
        return 1
    }
    mkdir -p -- "$user_data" || return 1
    # noclobber preserves existing customization, including a concurrent setup.
    if [[ ! -e $user_data/default.custom.yaml && ! -L $user_data/default.custom.yaml ]]; then
        (set -o noclobber; cat -- "$release_dir/rime/default.custom.yaml" > "$user_data/default.custom.yaml") || return 1
    fi
    # SIGKILL cannot run the previous helper's trap. The compositor control socket
    # survives helper recovery, so replace only its old IME instance. Bound all
    # manager calls and wait for the transient unit to be collected before reuse.
    load_state=$(timeout --kill-after=1s 2s systemctl --user show "$name" --property=LoadState --value) || return 1
    if [[ $load_state != not-found ]]; then
        timeout --kill-after=1s 6s systemctl --user stop "$name" || return 1
        deadline=$((SECONDS + 3))
        while [[ $load_state != not-found ]]; do
            ((SECONDS < deadline)) || return 1
            load_state=$(timeout --kill-after=1s 1s systemctl --user show "$name" --property=LoadState --value) || return 1
            if [[ $load_state != not-found ]]; then sleep .05; fi
        done
    fi
    for variable in HOME PATH LANG XDG_RUNTIME_DIR XDG_CONFIG_HOME XDG_CACHE_HOME XDG_DATA_HOME XDG_STATE_HOME \
                    DBUS_SESSION_BUS_ADDRESS XDG_CURRENT_DESKTOP XDG_SESSION_DESKTOP XDG_SESSION_TYPE \
                    FERESE_SOCKET FERESE_RIME_CONTROL; do
        if [[ -v $variable ]]; then environment+=("--setenv=$variable=${!variable}"); fi
    done
    if timeout --kill-after=1s 6s systemd-run --user --collect --quiet --no-block --unit="$name" --service-type=notify \
        --property=Restart=on-failure --property=RestartSec=1 \
        --property=StartLimitIntervalSec=60 --property=StartLimitBurst=5 \
        --property=WatchdogSec=10 --property=WatchdogSignal=SIGKILL \
        --property=TimeoutStartSec=45 --property=TimeoutStopSec=3 \
        --property=BindsTo=ferese-session.target --property=PartOf=ferese-session.target \
        "${environment[@]}" \
        /usr/bin/env -u WAYLAND_SOCKET -u FERESE_SHELL_CONTROL_SOCKET -u FERESE_PRIVATE_X11_COOKIE \
        WAYLAND_DISPLAY="$public_display" "$release_dir/ferese-rime" \
        --user-data "$user_data" --shared-data "$shared_data"; then
        rime_unit=$name
    else
        return 1
    fi
}
# Agent failures must not take down a healthy shell. The compositor supervises
# this helper (and creates fresh private connections) when the shell itself exits.
supervise_agent() {
    local child= delay=1 started
    trap 'trap - TERM INT; if [[ -n $child ]]; then kill "$child" 2>/dev/null || true; wait "$child" 2>/dev/null || true; fi; exit 0' TERM INT
    while true; do
        started=$SECONDS
        env -u WAYLAND_SOCKET -u FERESE_SHELL_CONTROL_SOCKET \
            WAYLAND_DISPLAY="${FERESE_PUBLIC_WAYLAND_DISPLAY:-${WAYLAND_DISPLAY:-}}" \
            "$release_dir/ferese-polkit-agent" &
        child=$!
        wait "$child" || true
        child=
        if ((SECONDS - started >= 60)); then delay=1; fi
        sleep "$delay" &
        child=$!
        wait "$child" || true
        child=
        if ((delay < 30)); then delay=$((delay * 2)); fi
        if ((delay > 30)); then delay=30; fi
    done
}
supervise_agent &
agent_pid=$!
"$release_dir/ferese-shell" &
shell_pid=$!
if ((manage_session && session_target_started)) && [[ ${FERESE_ENABLE_INPUT_METHOD:-0} == 1 ]]; then
    if ! start_rime; then
        echo 'Ferese: native Rime could not start; the desktop remains available.' >&2
    fi
fi
if ((manage_session)) && [[ ${FERESE_CLIENT_RESTART:-0} != 1 && -x $release_dir/feresectl ]]; then
    env WAYLAND_DISPLAY="${FERESE_PUBLIC_WAYLAND_DISPLAY:-${WAYLAND_DISPLAY:-}}" \
        "$release_dir/feresectl" autostart &
    autostart_pid=$!
fi
if wait "$shell_pid"; then
    status=0
else
    status=$?
fi
exit "$status"
