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

# ----------------------------- Logging -----------------------------
log() {
    [[ "$ENABLE_LOGGING" == true ]] && echo "[LOG] $(date '+%Y-%m-%d %H:%M:%S') $*"
}

# ----------------------------- Argument Parsing -----------------------------
parse_args() {
    DRY_RUN=${DRY_RUN:-false}
    for ARG in "$@"; do
        if [[ "$ARG" == *=* ]]; then
            VAR_NAME="${ARG%%=*}"
            VAR_VALUE="${ARG#*=}"
            if declare -p "$VAR_NAME" &>/dev/null; then
                printf -v "$VAR_NAME" '%s' "$VAR_VALUE"
                log "Overriding $VAR_NAME -> $VAR_VALUE"
            else
                echo "Warning: Unknown variable $VAR_NAME, ignoring."
            fi
        else
            case "$ARG" in
                --dry-run|-n)
                    DRY_RUN=true
                    ;;
                --log)
                    ENABLE_LOGGING=true
                    ;;
                --no-log)
                    ENABLE_LOGGING=false
                    ;;
                --help|-h)
                    echo "Usage: script [--dry-run|-n] [--log|--no-log] [VAR=value ...]"
                    exit 0
                    ;;
                *)
                    echo "Warning: Unknown argument $ARG"
                    ;;
            esac
        fi
    done
}

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

validate_int() {
    local name="$1"
    local value="$2"
    if ! [[ "${value:-}" =~ ^[0-9]+$ ]]; then
        echo "Error: $name must be a non-negative integer."
        exit 1
    fi
}

# ----------------------------- Host Detection & SSH -----------------------------
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="$HOST1"
    else
        echo "Error: Local hostname ($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
        echo "Error: No SSH key defined for $LOCAL_SERVER_NAME → $REMOTE_SERVER_NAME"
        exit 1
    fi

    echo "Local server: $LOCAL_SERVER_NAME, Remote server: $REMOTE_SERVER_NAME, SSH key: $SSH_KEY"
    log "Detected hosts successfully"
}

# ----------------------------- Remote Server IP -----------------------------
resolve_remote_ip() {
    REMOTE_SERVER=$(tailscale ip -4 "$REMOTE_SERVER_NAME" 2>/dev/null)
    if [[ -z "$REMOTE_SERVER" ]]; then
        echo "Error: Could not resolve Tailscale IP for $REMOTE_SERVER_NAME"
        exit 1
    fi
    echo "Remote IP: $REMOTE_SERVER"
    log "Resolved Tailscale IP successfully"
}

# ----------------------------- Container Helpers -----------------------------
declare -a RUNNING_CONTAINERS=()

stop_containers() {
    echo "Checking critical containers on $REMOTE_SERVER_NAME..."
    RUNNING_CONTAINERS=()
    for container in "${CRITICAL_CONTAINER_NAMES[@]}"; do
        STATUS=$(ssh -i "$SSH_KEY" root@"$REMOTE_SERVER" \
            "docker inspect -f '{{.State.Running}}' $container 2>/dev/null" || echo "false")
        log "Container $container running: $STATUS"
        if [[ "$STATUS" == "true" ]]; then
            echo "Stopping $container"
            RUNNING_CONTAINERS+=("$container")
            ssh -i "$SSH_KEY" root@"$REMOTE_SERVER" "docker stop $container"
        fi
    done
}

start_containers() {
    echo "Restarting containers on $REMOTE_SERVER_NAME..."
    for container in "${RUNNING_CONTAINERS[@]}"; do
        if [[ " ${DELAYED_CONTAINERS[*]} " == *" $container "* ]]; then
            echo "Delaying start of $container by ${CONTAINER_DELAY}s..."
            sleep "$CONTAINER_DELAY"
        fi
        ssh -i "$SSH_KEY" root@"$REMOTE_SERVER" "docker start $container"
        log "Container $container started"
    done
}

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