#!/bin/bash
# -----------------------------------------------------------------------------------------------
# ----------------------- Common Helpers for Unraid Scripts -------------------------------------
# -----------------------------------------------------------------------------------------------

# ----------------------------- Output Helpers -----------------------------
info() {
    echo "[INFO] $*"
}

warn() {
    echo "[WARN] $*"
}

error() {
    echo "[ERROR] $*"
}

log() {
    [[ "$ENABLE_LOGGING" == true ]] && echo "[LOG] $*"
}

# ----------------------------- Argument Parsing -----------------------------
parse_args() {
    DRY_RUN=${DRY_RUN:-false}
    ENABLE_LOGGING=${ENABLE_LOGGING:-false}

    for ARG in "$@"; do
        if [[ "$ARG" == *=* ]]; then
            VAR_NAME="${ARG%%=*}"
            VAR_VALUE="${ARG#*=}"

            case "$VAR_NAME" in
                LOG)
                    if [[ "$VAR_VALUE" == "true" ]]; then
                        ENABLE_LOGGING=true
                        info "Verbose logging enabled"
                    elif [[ "$VAR_VALUE" == "false" ]]; then
                        ENABLE_LOGGING=false
                    else
                        warn "Invalid value for LOG: $VAR_VALUE (use true/false)"
                    fi
                    ;;
                *)
                    if declare -p "$VAR_NAME" &>/dev/null; then
                        printf -v "$VAR_NAME" '%s' "$VAR_VALUE"
                        log "Overriding $VAR_NAME -> $VAR_VALUE"
                    else
                        warn "Unknown variable $VAR_NAME, ignoring."
                    fi
                    ;;
            esac

        else
            case "$ARG" in
                --dry-run|-n)
                    DRY_RUN=true
                    info "Dry-run mode enabled"
                    ;;
                --log)
                    ENABLE_LOGGING=true
                    info "Verbose logging enabled"
                    ;;
                --no-log)
                    ENABLE_LOGGING=false
                    ;;
                --status|--summary)
                    SHOW_STATUS=true
                    ;;    
                --help|-h)
                    echo "Usage: script <dir> [--dry-run|-n] [--log] [LOG=true] [VAR=value ...]"
                    exit 0
                    ;;
                *)
                    warn "Unknown argument $ARG"
                    ;;
            esac
        fi
    done
}

# ----------------------------- Validation -----------------------------
require_var() {
    local var="$1"
    if [[ -z "${!var:-}" ]]; then
        error "Required variable $var is not set."
        exit 1
    fi
}

validate_int() {
    local name="$1"
    local value="$2"

    if ! [[ "${value:-}" =~ ^[0-9]+$ ]]; then
        error "$name must be a non-negative integer."
        exit 1
    fi
}

# ----------------------------- Host Detection -----------------------------
detect_hosts() {
    LOCAL_HOSTNAME="$(hostname)"

    if [[ "$LOCAL_HOSTNAME" == "$HOST1" ]]; then
        LOCAL_SERVER_NAME="$HOST1"
        REMOTE_SERVER_NAME="$HOST2"
    elif [[ "$LOCAL_HOSTNAME" == "$HOST2" ]]; then
        LOCAL_SERVER_NAME="$HOST2"
        REMOTE_SERVER_NAME="$HOST1"
    else
        error "Local hostname ($LOCAL_HOSTNAME) not recognized."
        exit 1
    fi

    declare -A SSH_KEYS
    SSH_KEYS["$HOST1|$HOST2"]="$HOST1_SSH_KEY"
    SSH_KEYS["$HOST2|$HOST1"]="$HOST2_SSH_KEY"

    KEY_ID="$LOCAL_SERVER_NAME|$REMOTE_SERVER_NAME"
    SSH_KEY="${SSH_KEYS[$KEY_ID]}"

    if [[ -z "$SSH_KEY" ]]; then
        error "No SSH key defined for $LOCAL_SERVER_NAME → $REMOTE_SERVER_NAME"
        exit 1
    fi

    info "Local: $LOCAL_SERVER_NAME → Remote: $REMOTE_SERVER_NAME"
    log "SSH key: $SSH_KEY"
}

# ----------------------------- Remote IP -----------------------------
resolve_remote_ip() {
    log "Resolving Tailscale IP for $REMOTE_SERVER_NAME..."

    REMOTE_SERVER=$(tailscale ip -4 "$REMOTE_SERVER_NAME" 2>/dev/null)

    if [[ -z "$REMOTE_SERVER" ]]; then
        error "Could not resolve Tailscale IP for $REMOTE_SERVER_NAME"
        exit 1
    fi

    info "Remote IP: $REMOTE_SERVER"
}

# ----------------------------- Connectivity -----------------------------
check_remote_online() {
    log "Pinging $REMOTE_SERVER..."
    ping -c 1 "$REMOTE_SERVER" &>/dev/null
}

# ----------------------------- Containers -----------------------------
declare -a RUNNING_CONTAINERS=()

stop_containers() {
    if [[ ${#CRITICAL_CONTAINER_NAMES[@]} -eq 0 ]]; then
        log "No containers defined to stop"
        return
    fi

    info "Stopping containers on $REMOTE_SERVER_NAME..."
    RUNNING_CONTAINERS=()

    for container in "${CRITICAL_CONTAINER_NAMES[@]}"; do
        log "Checking container: $container"

        STATUS=$(ssh -i "$SSH_KEY" root@"$REMOTE_SERVER" \
            "docker inspect -f '{{.State.Running}}' $container 2>/dev/null" || echo "false")

        if [[ "$STATUS" == "true" ]]; then
            info "Stopping $container"
            RUNNING_CONTAINERS+=("$container")
            ssh -i "$SSH_KEY" root@"$REMOTE_SERVER" "docker stop $container"
        else
            log "$container already stopped"
        fi
    done
}

start_containers() {
    if [[ ${#RUNNING_CONTAINERS[@]} -eq 0 ]]; then
        log "No containers to restart"
        return
    fi

    info "Starting containers on $REMOTE_SERVER_NAME..."

    for container in "${RUNNING_CONTAINERS[@]}"; do
        if [[ " ${DELAYED_CONTAINERS[*]} " == *" $container "* ]]; then
            info "Delaying $container (${CONTAINER_DELAY}s)"
            sleep "$CONTAINER_DELAY"
        fi

        info "Starting $container"
        ssh -i "$SSH_KEY" root@"$REMOTE_SERVER" "docker start $container"
    done
}

# ----------------------------- Rsync Options -----------------------------
get_rsync_opts() {
    if [[ -n "${PROFILE_RSYNC_OPTS[$PROFILE_NAME]:-}" ]]; then
        read -r -a RSYNC_OPTS <<< "${PROFILE_RSYNC_OPTS[$PROFILE_NAME]}"
        log "Using profile rsync options: ${PROFILE_RSYNC_OPTS[$PROFILE_NAME]}"
    else
        RSYNC_OPTS=("${DEFAULT_RSYNC_OPTS[@]}")
        log "Using default rsync options: ${DEFAULT_RSYNC_OPTS[*]}"
    fi
}

# ----------------------------- Status Output -----------------------------
show_status() {
    echo "===== RSYNC STATUS ====="
    echo "Local:        $LOCAL_SERVER_NAME"
    echo "Remote:       $REMOTE_SERVER_NAME"
    echo "Remote IP:    $REMOTE_SERVER"
    echo "SSH Key:      $SSH_KEY"
    echo
    echo "Directory:    $DIRECTORY"
    echo "Profile:      $PROFILE_NAME"
    echo
    echo "Max Procs:    $MAX_RSYNC_PROCS"
    echo "Bandwidth:    $BW_LIMIT KB/s"
    echo "Retries:      $RETRY_COUNT"
    echo "Sleep:        $SLEEP"
    echo "Dry Run:      $DRY_RUN"
    echo
    echo "Containers:   ${CRITICAL_CONTAINER_NAMES[*]:-(none)}"
    echo "Delayed:      ${DELAYED_CONTAINERS[*]:-(none)}"
    echo
    echo "Excludes:     ${EXCLUDE_DIRS[*]:-(none)}"
    echo
    echo "Rsync Opts:"
    printf '  %s\n' "${RSYNC_OPTS[@]}"
    echo "========================="
}