#!/bin/bash
#
# steamify.sh - Steamify CachyOS
#
# Wizard that makes a CachyOS (KDE Plasma) install behave like SteamOS:
# boot into a Steam Deck-style gamescope session, switch to the Plasma
# desktop and back, and reset to gamescope on the next boot/logout.
#
# It opens with a menu that detects which components are on and turns
# them on or off to match what the user picks; turning one off restores
# what was there before (system files from .bak-gamescope-wizard backups,
# KDE settings from the undo journal in lib/state.sh). Components live in
# lib/, see TECHNICAL.md. Safe to re-run.

set -uo pipefail

# Release version, see CHANGELOG.md.
VERSION=2.2.0

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

for lib in common state packages login-manager single-user steam-desktop steam-machine fremont-poweroff hdmi-refresh cec boot-session vapor-theme steamos-extras bios desktop-shortcut wizard-shortcut menu backend; do
    # shellcheck source=/dev/null
    source "$SCRIPT_DIR/lib/$lib.sh"
done

require_root_helper

BACKEND=false
[[ "${1:-}" == --backend ]] && BACKEND=true

if [[ "$BACKEND" == false ]]; then
    echo -e "${c_bold}Steamify CachyOS${c_reset} v$VERSION"
    echo "Turn the SteamOS-style parts on or off. The menu shows what is on now;"
    echo "anything you turn off is put back the way it was."
fi

if ! command -v pacman >/dev/null 2>&1; then
    err "This doesn't look like an Arch/CachyOS system (no pacman found). Aborting."
    exit 1
fi

# Everything per-user (autologin user, Steam, theme, shortcut) is for the
# user running the script.
TARGET_USER="$(id -un)"

restart_needed() { [[ -n "${BIOS_NEEDS_RESTART:-}" || "$RESTART_FOR_LOGIN" == true ]]; }

restart_now() {
    if [[ -n "${BIOS_NEEDS_RESTART:-}" ]]; then
        warn "The BIOS update is written during this restart. Keep the power on and don't"
        warn "touch the machine until it has fully started again, even if the screen stays black."
    fi
    if [[ -n "${BIOS_DRY_RUN:-}" ]]; then
        ok "Dry run: would restart now (sudo reboot); not restarting."
        exit 0
    fi
    info "Restarting..."
    sudo reboot
    exit 0
}

after_run() {
    # After a run: back to the menu, or restart right away when something
    # that just ran needs it. Returns 1 when input has ended (scripted runs).
    local reply
    if ! restart_needed; then
        read -rp "Press Enter to go back to the menu... " _ || return 1
        return 0
    fi
    if [[ -n "${BIOS_NEEDS_RESTART:-}" ]]; then
        warn "The BIOS update is installed at the next restart."
    else
        info "The login changes take effect after a restart."
    fi
    while true; do
        read -rp "$(echo -e "${c_bold}[m]${c_reset} back to the menu   ${c_bold}[r]${c_reset} restart now: ")" reply || return 1
        case "$reply" in
            m|M|"") return 0 ;;
            r|R) restart_now ;;
            *) warn "Type m or r." ;;
        esac
    done
}

quit_prompt() {
    # On q: when something needs a restart, offer it (default yes); "n" goes
    # back to the menu, and the next q asks again. Returns 0 to show the menu
    # again, 1 to quit (nothing to restart, or input ended in scripted runs).
    local reply
    restart_needed || return 1
    echo
    if [[ -n "${BIOS_NEEDS_RESTART:-}" ]]; then
        warn "The BIOS update is written during the next restart. Keep the power on and"
        warn "don't touch the machine until it has fully started again, even if the screen stays black."
    else
        info "The changes take effect after a restart."
    fi
    read -rp "$(echo -e "${c_bold}Restart now?${c_reset} [Y/n] (n = back to the menu, Ctrl+C = quit without restarting) ")" reply || return 1
    case "$reply" in
        ""|y|Y) restart_now ;;
    esac
    return 0
}

# The graphical app (steamify-ui) drives the same components through
# lib/backend.sh instead of the menu.
if [[ "$BACKEND" == true ]]; then
    RESTART_FOR_LOGIN=false
    shift
    backend_main "$@"
    exit $?
fi

# Menu loop: after each run the menu comes back with the new state, until
# the user quits; the restart question comes then, once, for everything.
RESTART_FOR_LOGIN=false
SUDO_KEEPALIVE=false
while true; do
    detect_components
    if ! run_menu; then
        quit_prompt && continue
        break
    fi
    plan_changes

    if [[ ${#TO_DISABLE[@]} -eq 0 && ${#TO_ENABLE[@]} -eq 0 ]]; then
        ok "Everything is already the way you want it."
        read -rp "Press Enter to go back to the menu... " _ || break
        continue
    fi

    echo
    echo -e "${c_bold}This will:${c_reset}"
    for c in "${TO_DISABLE[@]}"; do
        if [[ "$c" == boot ]]; then echo "  - boot into: gamescope (from the next boot)"
        else echo "  - turn off: ${LABEL[$c]}"; fi
    done
    for c in "${TO_ENABLE[@]}"; do
        if [[ "$c" == boot ]]; then echo "  - boot into: desktop (from the next boot)"
        elif is_action "$c"; then echo "  - run:      ${LABEL[$c]%%:*} at your own risk (checks, then asks twice more)"
        elif [[ "${CURRENT[$c]}" == 1 ]]; then echo "  - re-apply: ${LABEL[$c]}"; else echo "  - turn on:  ${LABEL[$c]}"; fi
    done
    ask_yn "Go ahead?" y || { info "Nothing changed."; continue; }

    # Ask for the sudo password once and keep it fresh, instead of prompting
    # at random points during the run.
    sudo -n true 2>/dev/null || sudo -v || exit 1
    if [[ "$SUDO_KEEPALIVE" == false ]]; then
        SUDO_KEEPALIVE=true
        while true; do sudo -n true; sleep 50; kill -0 "$$" 2>/dev/null || exit; done 2>/dev/null &
    fi

    apply_changes
    # Login manager changes only take effect after a restart.
    [[ " ${TO_DISABLE[*]} ${TO_ENABLE[*]} " =~ \ (gaming|single|boot|kpin)\  ]] &&
        RESTART_FOR_LOGIN=true

    echo
    detect_components
    echo -e "${c_bold}Done. Current state:${c_reset}"
    for c in "${COMPONENTS[@]}"; do
        component_available "$c" && ! is_action "$c" || continue
        if [[ "$c" == boot ]]; then
            [[ "${CURRENT[gaming]}" == 1 ]] && echo "       └ boots into: $(boot_mode "${CURRENT[boot]}")"
        elif [[ -n "${PARENT[$c]:-}" ]]; then
            [[ "${CURRENT[${PARENT[$c]}]}" == 1 ]] || continue
            if [[ "${CURRENT[$c]}" == 1 ]]; then echo -e "       └ ${c_green}on ${c_reset} ${LABEL[$c]}"; else echo "       └ off  ${LABEL[$c]}"; fi
        elif [[ "${CURRENT[$c]}" == 1 ]]; then echo -e "  ${c_green}on ${c_reset} ${LABEL[$c]}"; else echo "  off  ${LABEL[$c]}"; fi
    done
    if [[ ${#FAILED[@]} -gt 0 ]]; then
        warn "These had problems (see above): ${FAILED[*]}"
    fi
    echo
    after_run || break
done
echo

if restart_needed; then
    # Only reached when input ended (scripted runs): never restart then.
    info "Not restarted; the changes take effect after a restart."
else
    info "Bye."
fi