#!/bin/bash
# ==============================================================================================
# ============================= Docker Update — Remaining ======================================
# ==============================================================================================
# Pulls the latest image for every running container NOT already covered by the daily or
# weekly update/restart cycles. Runs at the end of the weekly maintenance window.
#
# ── WHAT THIS COVERS ──────────────────────────────────────────────────────────────────────────
#   Daily update:   DAILY_RESTART_CONTAINERS  — auth stack, NPM, Dispatcharr, etc.
#   Weekly update:  WEEKLY_RESTART_CONTAINERS — NextCloud, AdGuard, Immich, etc.
#   This script:    everything else running on the system (media stack, utilities, etc.)
#
# Together the three scripts ensure every deployed container receives at least one image
# pull per week, with no container list to maintain here — it derives the remainder
# automatically from `docker ps` minus the two managed lists.
#
# ── EXCLUSION LOGIC ───────────────────────────────────────────────────────────────────────────
# Exclusion set = DAILY_RESTART_CONTAINERS + WEEKLY_RESTART_CONTAINERS (aliased by detect_hosts)
# Only running containers are targeted — stopped containers are intentionally excluded
# (stopped = likely paused intentionally; pulling while stopped adds no value).
#
# ── TOGGLE ────────────────────────────────────────────────────────────────────────────────────
#   WEEKLY_REMAINING_UPDATES=false in master.conf — skips all pulls, exits cleanly
#
# ── CONFIGURATION ─────────────────────────────────────────────────────────────────────────────
#   master.conf:         WEEKLY_REMAINING_UPDATES — enable/disable (default: true)
#   master_host*.conf:   HOST*_DAILY_RESTART_CONTAINERS  — excluded from this script
#                        HOST*_WEEKLY_RESTART_CONTAINERS — excluded from this script
#
# ── USAGE ─────────────────────────────────────────────────────────────────────────────────────
#   docker_update_remaining.sh              — normal run
#   docker_update_remaining.sh --dry-run    — show which containers would be pulled
#   docker_update_remaining.sh --log        — verbose output
#   docker_update_remaining.sh --status     — show config and exit
# ==============================================================================================

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

source "$SCRIPT_DIR/../load_config.sh"

parse_args "$@"

# ==============================================================================================
# ━━━ Setup ━━━
# ==============================================================================================
if [[ "$EUID" -ne 0 ]]; then
    error "Must be run as root"
    exit 1
fi

if ! command -v docker &>/dev/null; then
    error "Docker command not found"
    exit 1
fi

detect_hosts

if [[ "${WEEKLY_REMAINING_UPDATES:-true}" != "true" ]]; then
    log "WEEKLY_REMAINING_UPDATES=false — skipping remaining container updates"
    exit 0
fi

# ── Build exclusion set from daily + weekly managed lists ─────────────────────────────────────
declare -A EXCLUDED
for c in "${DAILY_RESTART_CONTAINERS[@]}"  "${WEEKLY_RESTART_CONTAINERS[@]}"; do
    [[ -n "$c" ]] && EXCLUDED["$c"]=1
done

# ── Get all running containers ────────────────────────────────────────────────────────────────
mapfile -t ALL_RUNNING < <(docker ps --format '{{.Names}}' 2>/dev/null | sort)

# ── Derive remainder: running minus excluded ──────────────────────────────────────────────────
REMAINING=()
for c in "${ALL_RUNNING[@]}"; do
    [[ -z "$c" ]] && continue
    [[ -n "${EXCLUDED[$c]:-}" ]] && continue
    REMAINING+=("$c")
done

# ==============================================================================================
# ━━━ Status ━━━
# ==============================================================================================
if [[ "$SHOW_STATUS" == true ]]; then
    echo ""
    echo "━━━━━ $ICON_SUMMARY STATUS ━━━━━"
    echo "$ICON_HOST       Identity:    $MY_ID ($LOCAL_SERVER_NAME)"
    echo "$ICON_GEAR       Enabled:     ${WEEKLY_REMAINING_UPDATES:-true}"
    echo "$ICON_CONTAINERS All running: ${#ALL_RUNNING[@]}"
    echo "$ICON_CONTAINERS Excluded:    ${!EXCLUDED[*]}"
    echo "$ICON_CONTAINERS Remaining:   ${REMAINING[*]:-none}"
    echo "━━━━━━━━━━━━━━━━━━━━━━━"
    exit 0
fi

if [[ ${#REMAINING[@]} -eq 0 ]]; then
    log "No remaining containers to update — all running containers are covered by daily/weekly lists"
    exit 0
fi

[[ "$DRY_RUN" == true ]] && warn "DRY RUN — no images will be pulled"

# ==============================================================================================
# ━━━ Pull Updates ━━━
# ==============================================================================================
echo ""
echo "━━━ $ICON_CONTAINERS Docker Update (Remaining) — $(date '+%Y-%m-%d %H:%M:%S') ━━━"
echo "$ICON_CONTAINERS Containers: ${REMAINING[*]}"
echo "$ICON_CONTAINERS Excluded (managed elsewhere): ${!EXCLUDED[*]}"
echo ""

START=$(date +%s)
UPDATED=()
UP_TO_DATE=()
FAILED=()

for container in "${REMAINING[@]}"; do
    [[ -z "$container" ]] && continue
    echo "━━━ $ICON_CONTAINERS $container ━━━"

    IMAGE=$(docker inspect --format='{{.Config.Image}}' "$container" 2>/dev/null)
    if [[ -z "$IMAGE" ]]; then
        warn "$container — could not determine image, skipping"
        FAILED+=("$container")
        echo ""
        continue
    fi

    log "$container — image: $IMAGE"

    if [[ "$DRY_RUN" == true ]]; then
        warn "DRY RUN — would pull: $IMAGE"
        UPDATED+=("$container")
        echo ""
        continue
    fi

    OLD_ID=$(docker image inspect "$IMAGE" --format='{{.Id}}' 2>/dev/null || echo "")

    echo "$ICON_SYNC  Pulling $IMAGE..."
    if docker pull "$IMAGE" 2>&1 | grep -E "^(Status:|Digest:|Error|error)" | sed 's/^/  /'; then
        NEW_ID=$(docker image inspect "$IMAGE" --format='{{.Id}}' 2>/dev/null || echo "")

        if [[ -n "$OLD_ID" ]] && [[ "$OLD_ID" != "$NEW_ID" ]]; then
            echo "$ICON_DONE  $container — updated ✅"
            UPDATED+=("$container")
        else
            log "$container — already up to date"
            UP_TO_DATE+=("$container")
        fi
    else
        warn "$container — pull failed ($IMAGE)"
        FAILED+=("$container")
    fi

    echo ""
done

END=$(date +%s)

# ==============================================================================================
# ━━━ Summary ━━━
# ==============================================================================================
echo "━━━━━ $ICON_SUMMARY DOCKER UPDATE (REMAINING) SUMMARY ━━━━━"
echo "$ICON_HOST       Identity:    $MY_ID ($LOCAL_SERVER_NAME)"
echo "$ICON_TIME       Duration:    $(format_duration $(( END - START )))"
echo "$ICON_CONTAINERS Scope:       ${#ALL_RUNNING[@]} running — ${#EXCLUDED[@]} managed = ${#REMAINING[@]} checked"
[[ ${#UPDATED[@]} -gt 0 ]]    && echo "$ICON_DONE       Updated:     ${UPDATED[*]}"
[[ ${#UP_TO_DATE[@]} -gt 0 ]] && echo "$ICON_RUNNING    Up to date:  ${UP_TO_DATE[*]}"
[[ ${#FAILED[@]} -gt 0 ]]     && echo "$ICON_ERROR      Failed:      ${FAILED[*]}"

if [[ "$DRY_RUN" == true ]]; then
    warn "DRY RUN — no images pulled"
elif [[ ${#FAILED[@]} -eq 0 ]]; then
    log "$ICON_DONE Status: done ✅ — ${#UPDATED[@]} updated, ${#UP_TO_DATE[@]} current"
else
    warn "Status: ${#FAILED[@]} pull(s) failed — containers continue on existing images"
fi
echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"

# Pull failures are non-fatal
exit 0