#!/usr/bin/env bash

### GLOBAL CONSTANTS ###
# ERROR CODES
readonly EC_MISSING_CONFIG=1
readonly EC_MISSING_FREERDP=2
readonly EC_NOT_IN_GROUP=3
readonly EC_FAIL_START=4
readonly EC_FAIL_RESUME=5
readonly EC_FAIL_DESTROY=6
readonly EC_SD_TIMEOUT=7
readonly EC_DIE_TIMEOUT=8
readonly EC_RESTART_TIMEOUT=9
readonly EC_NOT_EXIST=10
readonly EC_UNKNOWN=11
readonly EC_NO_IP=12
readonly EC_BAD_PORT=13
readonly EC_UNSUPPORTED_APP=14
readonly EC_INVALID_FLAVOR=15

# PATHS
readonly APPDATA_PATH="${HOME}/.local/share/winapps"
readonly SYS_APP_PATH="/usr/local/share/winapps"
readonly LASTRUN_PATH="${APPDATA_PATH}/lastrun"
readonly LOG_PATH="${APPDATA_PATH}/winapps.log"
readonly CONFIG_PATH="${HOME}/.config/winapps/winapps.conf"
readonly COMPOSE_PATH="${HOME}/.config/winapps/compose.yaml"
# shellcheck disable=SC2155 # Silence warnings regarding masking return values through simultaneous declaration and assignment.
readonly SCRIPT_DIR_PATH="$(cd "$(dirname "${BASH_SOURCE[0]}")" &>/dev/null && pwd)"

# OTHER
readonly VM_NAME="RDPWindows" # FOR 'libvirt' ONLY
readonly CONTAINER_NAME="WinApps" # FOR 'docker' AND 'podman' ONLY
readonly RDP_PORT=3389
readonly DOCKER_IP="127.0.0.1"
# shellcheck disable=SC2155 # Silence warnings regarding masking return values through simultaneous declaration and assignment.
readonly RUN="$(date)-${RANDOM}"

### GLOBAL VARIABLES ###
# WINAPPS CONFIGURATION FILE
RDP_USER=""
RDP_PASS=""
RDP_DOMAIN=""
RDP_IP=""
WAFLAVOR="docker"
RDP_FLAGS=""
FREERDP_COMMAND=""
RDP_SCALE=100
AUTOPAUSE="off"
AUTOPAUSE_TIME="300"
MULTIMON="false"
DEBUG="true"
MULTI_FLAG=""

# OTHER
FREERDP_PID=-1

### TRAPS ###
# Catch SIGINT (CTRL+C) to call 'waCleanUp'.
trap waCleanUp SIGINT

### FUNCTIONS ###
# Name: 'waCleanUp'
# Role: Clean up remains prior to exit.
waCleanUp() {
    # Kill FreeRDP.
    [ "$FREERDP_PID" -gt 0 ] && kill -9 "$FREERDP_PID" &>/dev/null

    # Remove '.cproc' file.
    [ -f "${APPDATA_PATH}/FreeRDP_Process_${FREERDP_PID}.cproc" ] && rm "${APPDATA_PATH}/FreeRDP_Process_${FREERDP_PID}.cproc" &>/dev/null

    # Terminate script.
    exit 1
}

# Name: 'waThrowExit'
# Role: Throw an error message and exit the script.
function waThrowExit() {
    # Declare variables.
    local ERR_CODE="$1"

    # Throw error.
    case "$ERR_CODE" in
    "$EC_MISSING_CONFIG")
        # Missing WinApps configuration file.
        dprint "ERROR: MISSING WINAPPS CONFIGURATION FILE. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "The WinApps configuration file is missing.\nPlease create a WinApps configuration file at '${CONFIG_PATH}'."
        ;;
    "$EC_MISSING_FREERDP")
        dprint "ERROR: FREERDP VERSION 3 IS NOT INSTALLED. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "FreeRDP version 3 is not installed."
        ;;
    "$EC_NOT_IN_GROUP")
        dprint "ERROR: USER NOT PART OF REQUIRED GROUPS. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "The user $(whoami) is not part of the required groups.
Please run:
    sudo usermod -a -G libvirt $(whoami)
    sudo usermod -a -G kvm $(whoami)"
        ;;
    "$EC_FAIL_START")
        dprint "ERROR: WINDOWS FAILED TO START. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Windows failed to start."
        ;;
    "$EC_FAIL_RESUME")
        dprint "ERROR: WINDOWS FAILED TO RESUME. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Windows failed to resume."
        ;;
    "$EC_FAIL_DESTROY")
        dprint "ERROR: WINDOWS FAILED TO IMMEDIATELY UNGRACEFULLY SHUT DOWN WINDOWS. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Failed to ungracefully shut down Windows."
        ;;
    "$EC_SD_TIMEOUT")
        dprint "ERROR: WINDOWS TOOK TOO LONG TO SHUT DOWN. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Windows took too long to shut down."
        ;;
    "$EC_DIE_TIMEOUT")
        dprint "ERROR: WINDOWS TOOK TOO LONG TO SHUT DOWN. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Windows took too long to die."
        ;;
    "$EC_RESTART_TIMEOUT")
        dprint "ERROR: WINDOWS TOOK TOO LONG TO RESTART. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Windows took too long to restart."
        ;;
    "$EC_NOT_EXIST")
        dprint "ERROR: WINDOWS NONEXISTENT. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Windows does not exist."
        ;;
    "$EC_UNKNOWN")
        dprint "ERROR: UNKNOWN CONTAINER ERROR. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Unknown Windows container error."
        ;;
    "$EC_NO_IP")
        dprint "ERROR: WINDOWS UNREACHABLE. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Windows is unreachable.\nPlease ensure Windows is assigned an IP address."
        ;;
    "$EC_BAD_PORT")
        dprint "ERROR: RDP PORT CLOSED. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "The Windows RDP port '${RDP_PORT}' is closed.\nPlease ensure Remote Desktop is correctly configured on Windows."
        ;;
    "$EC_UNSUPPORTED_APP")
        dprint "ERROR: APPLICATION NOT FOUND. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Application not found.\nPlease ensure the program is correctly configured as an officially supported application."
        ;;
    "$EC_INVALID_FLAVOR")
        dprint "ERROR: INVALID FLAVOR. EXITING."
        notify-send --expire-time=8000 --icon="dialog-error" --app-name="WinApps" --urgency="low" "WinApps" "Invalid WinApps flavor.\nPlease ensure 'docker', 'podman' or 'libvirt' are specified as the flavor in the WinApps configuration file."
        ;;
    esac

    # Terminate the script.
    exit "$ERR_CODE"
}

# Name: 'dprint'
# Role: Conditionally print debug messages to a log file, creating it if it does not exist.
function dprint() {
    [ "$DEBUG" = "true" ] && echo "[$RUN] $1" >>"$LOG_PATH"
}

# Name: 'waFixScale'
# Role: Since FreeRDP only supports '/scale' values of 100, 140 or 180, find the closest supported argument to the user's configuration.
function waFixScale() {
    # Define variables.
    local OLD_SCALE=100
    local VALID_SCALE_1=100
    local VALID_SCALE_2=140
    local VALID_SCALE_3=180

    # Check for an unsupported value.
    if [ "$RDP_SCALE" != "$VALID_SCALE_1" ] && [ "$RDP_SCALE" != "$VALID_SCALE_2" ] && [ "$RDP_SCALE" != "$VALID_SCALE_3" ]; then
        # Save the unsupported scale.
        OLD_SCALE="$RDP_SCALE"

        # Calculate the absolute differences.
        local DIFF_1=$(( RDP_SCALE > VALID_SCALE_1 ? RDP_SCALE - VALID_SCALE_1 : VALID_SCALE_1 - RDP_SCALE ))
        local DIFF_2=$(( RDP_SCALE > VALID_SCALE_2 ? RDP_SCALE - VALID_SCALE_2 : VALID_SCALE_2 - RDP_SCALE ))
        local DIFF_3=$(( RDP_SCALE > VALID_SCALE_3 ? RDP_SCALE - VALID_SCALE_3 : VALID_SCALE_3 - RDP_SCALE ))

        # Set the final scale to the valid scale value with the smallest absolute difference.
        if (( DIFF_1 <= DIFF_2 && DIFF_1 <= DIFF_3 )); then
            RDP_SCALE="$VALID_SCALE_1"
        elif (( DIFF_2 <= DIFF_1 && DIFF_2 <= DIFF_3 )); then
            RDP_SCALE="$VALID_SCALE_2"
        else
            RDP_SCALE="$VALID_SCALE_3"
        fi

        # Print feedback.
        dprint "WARNING: Unsupported RDP_SCALE value '${OLD_SCALE}'. Defaulting to '${RDP_SCALE}'."
        notify-send --expire-time=4000 --icon="dialog-warning" --app-name="WinApps" --urgency="low" "WinApps" "Unsupported RDP_SCALE value '${OLD_SCALE}'.\nDefaulting to '${RDP_SCALE}'."
    fi
}

# Name: 'waLoadConfig'
# Role: Load the variables within the WinApps configuration file.
function waLoadConfig() {
    # Load WinApps configuration file.
    if [ -f "$CONFIG_PATH" ]; then
        # shellcheck source=/dev/null # Exclude WinApps configuration file from being checked by ShellCheck.
        source "$CONFIG_PATH"
    else
        waThrowExit $EC_MISSING_CONFIG
    fi

    # Update 'MULTI_FLAG' based on 'MULTIMON'.
    MULTI_FLAG=$([[ $MULTIMON == "true" ]] && echo "/multimon" || echo "+span")

    # Update $RDP_SCALE.
    waFixScale

    # Update $AUTOPAUSE_TIME.
    # RemoteApp RDP sessions take, at minimum, 20 seconds to be terminated by the Windows server.
    # Hence, subtract 20 from the timeout specified by the user, as a 'built in' timeout of 20 seconds will occur.
    # Source: https://techcommunity.microsoft.com/t5/security-compliance-and-identity/terminal-services-remoteapp-8482-session-termination-logic/ba-p/246566
    AUTOPAUSE_TIME=$((AUTOPAUSE_TIME - 20))
    AUTOPAUSE_TIME=$((AUTOPAUSE_TIME < 0 ? 0 : AUTOPAUSE_TIME))
}

# Name: 'waLastRun'
# Role: Determine the last time this script was run.
function waLastRun() {
    # Declare variables.
    local LAST_RUN_UNIX_TIME=0
    local CURR_RUN_UNIX_TIME=0

    # Store the time this script was run last as a unix timestamp.
    if [ -f "$LASTRUN_PATH" ]; then
        LAST_RUN_UNIX_TIME=$(stat -t -c %Y "$LASTRUN_PATH")
        dprint "LAST_RUN: ${LAST_RUN_UNIX_TIME}"
    fi

    # Update the file modification time with the current time.
    touch "$LASTRUN_PATH"
    CURR_RUN_UNIX_TIME=$(stat -t -c %Y "$LASTRUN_PATH")
    dprint "THIS_RUN: ${CURR_RUN_UNIX_TIME}"
}

# Name: 'waGetFreeRDPCommand'
# Role: Determine the correct FreeRDP command to use.
function waGetFreeRDPCommand() {
    # Declare variables.
    local FREERDP_MAJOR_VERSION="" # Stores the major version of the installed copy of FreeRDP.

    # Attempt to set a FreeRDP command if the command variable is empty.
    if [ -z "$FREERDP_COMMAND" ]; then
        # Check for 'xfreerdp'.
        if command -v xfreerdp &>/dev/null; then
            # Check FreeRDP major version is 3 or greater.
            FREERDP_MAJOR_VERSION=$(xfreerdp --version | head -n 1 | grep -o -m 1 '\b[0-9]\S*' | head -n 1 | cut -d'.' -f1)
            if [[ $FREERDP_MAJOR_VERSION =~ ^[0-9]+$ ]] && ((FREERDP_MAJOR_VERSION >= 3)); then
                FREERDP_COMMAND="xfreerdp"
            fi
        fi

        # Check for 'xfreerdp3' command as a fallback option.
        if [ -z "$FREERDP_COMMAND" ]; then
            if command -v xfreerdp3 &>/dev/null; then
                # Check FreeRDP major version is 3 or greater.
                FREERDP_MAJOR_VERSION=$(xfreerdp3 --version | head -n 1 | grep -o -m 1 '\b[0-9]\S*' | head -n 1 | cut -d'.' -f1)
                if [[ $FREERDP_MAJOR_VERSION =~ ^[0-9]+$ ]] && ((FREERDP_MAJOR_VERSION >= 3)); then
                    FREERDP_COMMAND="xfreerdp3"
                fi
            fi
        fi

        # Check for FreeRDP Flatpak (fallback option).
        if [ -z "$FREERDP_COMMAND" ]; then
            if command -v flatpak &>/dev/null; then
                if flatpak list --columns=application | grep -q "^com.freerdp.FreeRDP$"; then
                    # Check FreeRDP major version is 3 or greater.
                    FREERDP_MAJOR_VERSION=$(flatpak list --columns=application,version | grep "^com.freerdp.FreeRDP" | awk '{print $2}' | cut -d'.' -f1)
                    if [[ $FREERDP_MAJOR_VERSION =~ ^[0-9]+$ ]] && ((FREERDP_MAJOR_VERSION >= 3)); then
                        FREERDP_COMMAND="flatpak run --command=xfreerdp com.freerdp.FreeRDP"
                    fi
                fi
            fi
        fi
    fi

    if command -v "$FREERDP_COMMAND" &>/dev/null || [ "$FREERDP_COMMAND" = "flatpak run --command=xfreerdp com.freerdp.FreeRDP" ]; then
        dprint "Using FreeRDP command '${FREERDP_COMMAND}'."

        # Append additional flags or parameters to FreeRDP.
        # These additional flags are loaded prior in 'waLoadConfig'.
        [[ -n $RDP_FLAGS ]] && FREERDP_COMMAND="${FREERDP_COMMAND} ${RDP_FLAGS}"
    else
        waThrowExit "$EC_MISSING_FREERDP"
    fi
}

# Name: 'waCheckGroupMembership'
# Role: Ensures the current user is part of the required groups.
function waCheckGroupMembership() {
    # Identify groups the current user belongs to.
    # shellcheck disable=SC2155 # Silence warnings regarding masking return values through simultaneous declaration and assignment.
    local USER_GROUPS=$(groups "$(whoami)")

    if ! (echo "$USER_GROUPS" | grep -q -E "\blibvirt\b") || ! (echo "$USER_GROUPS" | grep -q -E "\bkvm\b"); then
        waThrowExit "$EC_NOT_IN_GROUP"
    fi
}

# Name: 'waCheckVMRunning'
# Role: Check if the Windows 'libvirt' VM is running, and attempt to start it if it is not.
function waCheckVMRunning() {
    # Declare exit status variable.
    local EXIT_STATUS=0

    # Declare timer variables.
    local TIME_ELAPSED=0
    local TIME_LIMIT=60
    local TIME_INTERVAL=5

    # Attempt to run the Windows virtual machine.
    # Note: States 'running' and 'idle' do not require intervention, and are not checked for.
    if (virsh list --all --name | xargs | grep -wq "$VM_NAME"); then
        if (virsh list --state-shutoff --name | xargs | grep -wq "$VM_NAME"); then
            dprint "WINDOWS SHUT OFF. BOOTING WINDOWS."
            notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Booting Windows."
            virsh start "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_START
            if (virsh list --state-paused --name | xargs | grep -wq "$VM_NAME"); then
                dprint "WINDOWS PAUSED. RESUMING WINDOWS."
                notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Resuming Windows."
                virsh resume "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_RESUME
            fi
        elif (virsh list --state-paused --name | xargs | grep -wq "$VM_NAME"); then
            dprint "WINDOWS PAUSED. RESUMING WINDOWS."
            notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Resuming Windows."
            virsh resume "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_RESUME
        elif (virsh list --state-other --name | xargs | grep -wq "$VM_NAME"); then
            if (virsh domstate "$VM_NAME" | xargs | grep -wq "shutdown"); then
                dprint "WINDOWS SHUTTING DOWN. WAITING."
                notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Windows is currently shutting down.\nIt will automatically restart once the shutdown process is complete."
                EXIT_STATUS=$EC_SD_TIMEOUT
                while (( TIME_ELAPSED < TIME_LIMIT )); do
                    if (virsh list --state-shutoff --name | xargs | grep -wq "$VM_NAME"); then
                        EXIT_STATUS=0
                        dprint "WINDOWS SHUT OFF. BOOTING WINDOWS."
                        notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Booting Windows."
                        virsh start "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_START
                        break
                    fi
                    sleep $TIME_INTERVAL
                    TIME_ELAPSED=$((TIME_ELAPSED + TIME_INTERVAL))
                done
            elif (virsh domstate "$VM_NAME" | xargs | grep -wq "crashed"); then
                dprint "WINDOWS CRASHED. DESTROYING WINDOWS."
                notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Windows experienced an unexpected crash.\nAttempting to restart Windows."
                virsh destroy "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_DESTROY
                if [ "$EXIT_STATUS" -eq 0 ]; then
                    dprint "WINDOWS DESTROYED. BOOTING WINDOWS."
                    notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Booting Windows."
                    virsh start "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_START
                fi
            elif (virsh domstate "$VM_NAME" | xargs | grep -wq "dying"); then
                dprint "WINDOWS DYING. WAITING."
                notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Windows is currently shutting down unexpectedly.\nIt will try to restart once the shutdown process finishes."
                EXIT_STATUS=$EC_DIE_TIMEOUT
                while (( TIME_ELAPSED < TIME_LIMIT )); do
                    if (virsh domstate "$VM_NAME" | xargs | grep -wq "crashed"); then
                        EXIT_STATUS=0
                        dprint "WINDOWS CRASHED. DESTROYING WINDOWS."
                        notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Windows experienced an unexpected crash.\nAttempting to restart Windows."
                        virsh destroy "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_DESTROY
                        if [ "$EXIT_STATUS" -eq 0 ]; then
                            dprint "WINDOWS DESTROYED. BOOTING WINDOWS."
                            notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Booting Windows."
                            virsh start "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_START
                        fi
                        break
                    elif (virsh list --state-shutoff --name | xargs | grep -wq "$VM_NAME"); then
                        EXIT_STATUS=0
                        dprint "WINDOWS SHUT OFF. BOOTING WINDOWS."
                        notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Booting Windows."
                        virsh start "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_START
                        break
                    fi
                    sleep $TIME_INTERVAL
                    TIME_ELAPSED=$((TIME_ELAPSED + TIME_INTERVAL))
                done
            elif (virsh domstate "$VM_NAME" | xargs | grep -wq "pmsuspended" ); then
                dprint "WINDOWS SUSPENDED. RESUMING WINDOWS."
                virsh resume "$VM_NAME" &>/dev/null || EXIT_STATUS=$EC_FAIL_RESUME
            fi
        fi
    else
        EXIT_STATUS=$EC_NOT_EXIST
    fi

    # Handle non-zero exit statuses.
    [ "$EXIT_STATUS" -ne 0 ] && waThrowExit "$EXIT_STATUS"
}

# Name: 'waCheckContainerRunning'
# Role: Throw an error if the Docker container is not running.
function waCheckContainerRunning() {
    # Declare variables.
    local EXIT_STATUS=0
    local CONTAINER_STATE=""
    local COMPOSE_COMMAND=""
    local TIME_ELAPSED=0
    local TIME_LIMIT=60
    local TIME_INTERVAL=5

    # Determine the state of the container.
    CONTAINER_STATE=$("$WAFLAVOR" inspect --format='{{.State.Status}}' "$CONTAINER_NAME")

    # Determine the compose command.
    case "$WAFLAVOR" in
        "docker") COMPOSE_COMMAND="docker compose" ;;
        "podman") COMPOSE_COMMAND="podman-compose" ;;
    esac

    # Check container state.
    # Note: Errors DO NOT result in non-zero exit statuses.
    # Docker: 'created', 'restarting', 'running', 'removing', 'paused', 'exited' or 'dead'.
    # Podman: 'created', 'running', 'paused', 'exited' or 'unknown'.
    case "$CONTAINER_STATE" in
        "created")
            dprint "WINDOWS CREATED. BOOTING WINDOWS."
            notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Booting Windows."
            $COMPOSE_COMMAND --file "$COMPOSE_PATH" start &>/dev/null
            ;;
        "restarting")
            dprint "WINDOWS RESTARTING. WAITING."
            notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Windows is currently restarting. Please wait."
            EXIT_STATUS=$EC_RESTART_TIMEOUT
            while (( TIME_ELAPSED < TIME_LIMIT )); do
                if [[ $("$WAFLAVOR" inspect --format='{{.State.Status}}' "$CONTAINER_NAME") == "running" ]]; then
                    EXIT_STATUS=0
                    dprint "WINDOWS RESTARTED."
                    notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Restarted Windows."
                    break
                fi
                sleep $TIME_INTERVAL
                TIME_ELAPSED=$((TIME_ELAPSED + TIME_INTERVAL))
            done
            ;;
        "paused")
            dprint "WINDOWS PAUSED. RESUMING WINDOWS."
            notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Resuming Windows."
            $COMPOSE_COMMAND --file "$COMPOSE_PATH" unpause &>/dev/null
            ;;
        "exited")
            dprint "WINDOWS SHUT OFF. BOOTING WINDOWS."
            notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Booting Windows."
            $COMPOSE_COMMAND --file "$COMPOSE_PATH" start &>/dev/null
            ;;
        "dead")
            dprint "WINDOWS DEAD. RECREATING WINDOWS CONTAINER."
            notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Re-creating and booting Windows."
            $COMPOSE_COMMAND --file "$COMPOSE_PATH" down &>/dev/null && $COMPOSE_COMMAND --file "$COMPOSE_PATH" up -d &>/dev/null
            ;;
        "unknown")
            EXIT_STATUS=$EC_UNKNOWN
            ;;
    esac

    # Handle non-zero exit statuses.
    [ "$EXIT_STATUS" -ne 0 ] && waThrowExit "$EXIT_STATUS"
}

# Name: 'waCheckPortOpen'
# Role: Assesses whether the RDP port on Windows is open.
function waCheckPortOpen() {
    # Declare variables.
    local VM_MAC="" # Stores the MAC address of the Windows VM.
    local TIME_ELAPSED=0
    local TIME_LIMIT=30
    local TIME_INTERVAL=5

    # Obtain Windows VM IP Address ('libvirt' ONLY)
    # Note: 'RDP_IP' should not be empty if 'WAFLAVOR' is 'docker', since it is set to localhost before this function is called.
    if [ -z "$RDP_IP" ] && [ "$WAFLAVOR" = "libvirt" ]; then
        VM_MAC=$(virsh domiflist "$VM_NAME" | grep -oE "([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})") # VM MAC address.

        while (( TIME_ELAPSED < TIME_LIMIT )); do
            if [ "$TIME_ELAPSED" -eq "$TIME_INTERVAL" ]; then
                notify-send --expire-time=4000 --icon="dialog-info" --app-name="WinApps" --urgency="low" "WinApps" "Requesting Windows IP address..."
            fi
            RDP_IP=$(ip neigh show | grep "$VM_MAC" | grep -oE "([0-9]{1,3}\.){3}[0-9]{1,3}") # VM IP address.
            [ -n "$RDP_IP" ] && break
            sleep $TIME_INTERVAL
            TIME_ELAPSED=$((TIME_ELAPSED + TIME_INTERVAL))
        done

        [ -z "$RDP_IP" ] && waThrowExit "$EC_NO_IP"
    fi

    # Check for an open RDP port.
    timeout 10 nc -z "$RDP_IP" "$RDP_PORT" &>/dev/null || waThrowExit "$EC_BAD_PORT"
}

# Name: 'waRunCommand'
# Role: Run the requested WinApps command.
function waRunCommand() {
    # Declare variables.
    local ICON=""
    local FILE_PATH=""

    # Run option.
    if [ "$1" = "windows" ]; then
        # Update timeout (since there is no 'in-built' 20 second delay for full RDP sessions post-logout).
        AUTOPAUSE_TIME=$((AUTOPAUSE_TIME + 20))

        # Open Windows RDP session.
        dprint "WINDOWS"
        $FREERDP_COMMAND \
            /d:"$RDP_DOMAIN" \
            /u:"$RDP_USER" \
            /p:"$RDP_PASS" \
            /scale:"$RDP_SCALE" \
            +dynamic-resolution \
            +auto-reconnect \
            +home-drive \
            /sound \
            /microphone \
            /wm-class:"Microsoft Windows" \
            /t:"Windows RDP Session [$RDP_IP]" \
            /v:"$RDP_IP" &>/dev/null &

        # Capture the process ID.
        FREERDP_PID=$!
    elif [ "$1" = "manual" ]; then
        # Open specified application.
        dprint "MANUAL: ${2}"
        $FREERDP_COMMAND \
            /cert:tofu \
            /d:"$RDP_DOMAIN" \
            /u:"$RDP_USER" \
            /p:"$RDP_PASS" \
            /scale:"$RDP_SCALE" \
            +auto-reconnect \
            +clipboard \
            +home-drive \
            /sound \
            /microphone \
            -wallpaper \
            +dynamic-resolution \
            "$MULTI_FLAG" \
            /app:program:"$2" \
            /v:"$RDP_IP" &>/dev/null &

        # Capture the process ID.
        FREERDP_PID=$!
    else
        # Script summoned from right-click menu or application icon (plus/minus a file path).
        if [ -e "${SCRIPT_DIR_PATH}/../apps/${1}/info" ]; then
            # shellcheck source=/dev/null # Exclude this file from being checked by ShellCheck.
            source "${SCRIPT_DIR_PATH}/../apps/${1}/info"
            ICON="${SCRIPT_DIR_PATH}/../apps/${1}/icon.svg"
        elif [ -e "${APPDATA_PATH}/apps/${1}/info" ]; then
            # shellcheck source=/dev/null # Exclude this file from being checked by ShellCheck.
            source "${APPDATA_PATH}/apps/${1}/info"
            ICON="${APPDATA_PATH}/apps/${1}/icon.svg"
        elif [ -e "${SYS_APP_PATH}/apps/${1}/info" ]; then
            # shellcheck source=/dev/null # Exclude this file from being checked by ShellCheck.
            source "${SYS_APP_PATH}/apps/${1}/info"
            ICON="${SYS_APP_PATH}/apps/${1}/icon.svg"
        else
            waThrowExit "$EC_UNSUPPORTED_APP"
        fi

        # Check if a file path was specified, and pass this to the application.
        if [ -z "$2" ]; then
            # No file path specified.
            $FREERDP_COMMAND \
                /d:"$RDP_DOMAIN" \
                /u:"$RDP_USER" \
                /p:"$RDP_PASS" \
                /scale:"$RDP_SCALE" \
                +auto-reconnect \
                +clipboard \
                +home-drive \
                /sound \
                /microphone \
                -wallpaper \
                +dynamic-resolution \
                "$MULTI_FLAG" \
                /wm-class:"$FULL_NAME" \
                /app:program:"$WIN_EXECUTABLE",icon:"$ICON",name:"$FULL_NAME" \
                /v:"$RDP_IP" &>/dev/null &

            # Capture the process ID.
            FREERDP_PID=$!
        else
            # Convert path from UNIX to Windows style.
            FILE_PATH=$(echo "$2" | sed \
                -e 's|'"${HOME}"'|\\\\tsclient\\home|' \
                -e 's|/|\\|g')
            dprint "UNIX_FILE_PATH: ${2}"
            dprint "WINDOWS_FILE_PATH: ${FILE_PATH}"

            $FREERDP_COMMAND \
                /cert:tofu \
                /d:"$RDP_DOMAIN" \
                /u:"$RDP_USER" \
                /p:"$RDP_PASS" \
                /scale:"$RDP_SCALE" \
                +auto-reconnect \
                +clipboard \
                +home-drive \
                /sound \
                /microphone \
                -wallpaper \
                +dynamic-resolution \
                "$MULTI_FLAG" \
                /wm-class:"$FULL_NAME" \
                /app:program:"$WIN_EXECUTABLE",icon:"$ICON",name:$"FULL_NAME",cmd:\""$FILE_PATH"\" \
                /v:"$RDP_IP" &>/dev/null &

            # Capture the process ID.
            FREERDP_PID=$!
        fi
    fi

    if [ "$FREERDP_PID" -ne -1 ]; then
        # Create a file with the process ID.
        touch "${APPDATA_PATH}/FreeRDP_Process_${FREERDP_PID}.cproc"

        # Wait for the process to terminate.
        wait $FREERDP_PID

        # Remove the file with the process ID.
        rm "${APPDATA_PATH}/FreeRDP_Process_${FREERDP_PID}.cproc" &>/dev/null
    fi
}

# Name: 'waCheckIdle'
# Role: Suspend Windows if idle.
function waCheckIdle() {
    # Declare variables
    local TIME_INTERVAL=10
    local TIME_ELAPSED=0
    local SUSPEND_WINDOWS=0

    # Prevent 'autopause' functionality with unsupported Windows backends.
    if [ "$WAFLAVOR" != "manual" ] && [ "$WAFLAVOR" != "docker" ]; then
        # Check if there are no WinApps-related FreeRDP processes running.
        if ! ls "$APPDATA_PATH"/FreeRDP_Process_*.cproc &>/dev/null; then
            SUSPEND_WINDOWS=1
            while (( TIME_ELAPSED < AUTOPAUSE_TIME )); do
                if ls "$APPDATA_PATH"/FreeRDP_Process_*.cproc &>/dev/null; then
                    SUSPEND_WINDOWS=0
                    break
                fi
                sleep $TIME_INTERVAL
                TIME_ELAPSED=$((TIME_ELAPSED + TIME_INTERVAL))
            done
        fi

        # Hibernate/Pause Windows.
        if [ "$SUSPEND_WINDOWS" -eq 1 ]; then
            dprint "IDLE FOR ${AUTOPAUSE_TIME} SECONDS. SUSPENDING WINDOWS."
            notify-send --expire-time=8000 --icon="info" --app-name="WinApps" --urgency="low" "WinApps" "Pausing Windows due to inactivity."
            if [ "$WAFLAVOR" = "docker" ]; then
                docker compose --file "$COMPOSE_PATH" pause &>/dev/null
            elif [ "$WAFLAVOR" = "podman" ]; then
                podman-compose --file "$COMPOSE_PATH" pause &>/dev/null
            elif [ "$WAFLAVOR" = "libvirt" ]; then
                virsh suspend "$VM_NAME" &>/dev/null
            fi
        fi
    fi
}

### MAIN LOGIC ###
#set -x # Enable for debugging.
dprint "START"
dprint "SCRIPT_DIR: ${SCRIPT_DIR_PATH}"
dprint "SCRIPT_ARGS: ${*}"
dprint "HOME_DIR: ${HOME}"
mkdir -p "$APPDATA_PATH"
waLastRun
waLoadConfig
waGetFreeRDPCommand

# If using podman backend, modify the FreeRDP command to enter a new namespace.
if [ "$WAFLAVOR" = "podman" ]; then
    FREERDP_COMMAND="podman unshare --rootless-netns ${FREERDP_COMMAND}"
fi

if [ "$WAFLAVOR" = "docker" ] || [ "$WAFLAVOR" = "podman" ]; then
    RDP_IP="$DOCKER_IP"
    waCheckContainerRunning
elif [ "$WAFLAVOR" = "libvirt" ]; then
    waCheckGroupMembership
    waCheckVMRunning
elif [ "$WAFLAVOR" = "manual" ]; then
    waCheckPortOpen
else
    waThrowExit "$EC_INVALID_FLAVOR"
fi

waCheckPortOpen
waRunCommand "$@"

if [[ "$AUTOPAUSE" == "on" ]]; then
    waCheckIdle
fi

dprint "END"