#!/bin/bash
# Kanboard backup — tier-0 hardening (kb#158, A2A-26, DESIGN-a2a-agents.md v2.1 §6c).
# Mirrors the vaultwarden backup.sh pattern (same repo, ~/agap_git/vaultwarden/backup.sh):
# scheduled dump -> /mnt/backups, retention of last 5, Zabbix freshness trapper.
#
# Runs every 3 days via alvis's user crontab (NOT root crontab like vaultwarden's --
# /mnt/backups/kanboard was bootstrapped chown'd to alvis specifically so this backup,
# like the rest of the kanboard tooling, needs no root/sudo at all. alvis is in the
# `docker` group so `docker exec`/`docker cp` need no privilege escalation either).
#
# DB dump method: kanboard's container has no sqlite3 CLI and no PHP `sqlite3`
# extension (only pdo_sqlite) -- checked directly (kb#158). Instead we run SQLite's
# own `VACUUM INTO` via PDO, which is SQLite's supported way to take an atomic,
# consistent online snapshot of a live database (safe against concurrent writers,
# same safety property `vaultwarden backup` gives us for that service).

set -euo pipefail

BACKUP_DIR="/mnt/backups/kanboard"
ZABBIX_TOKEN_FILE="/home/alvis/.zabbix_token"
ZABBIX_URL="http://192.168.1.4:81/api_jsonrpc.php"
ZABBIX_ITEM_ID="70605"   # kanboard.backup.ts on host AgapHost (10776)

DATE=$(date '+%Y%m%d-%H%M')
DEST="$BACKUP_DIR/$DATE"
TMP_NAME="backup_${DATE}.sqlite"

mkdir -p "$DEST"

# Online, consistent snapshot via SQLite's VACUUM INTO (PDO sqlite driver is present
# in the image; the sqlite3 CLI/extension is not, so this replaces the vaultwarden
# `docker exec vaultwarden /vaultwarden backup` equivalent for this service).
docker exec kanboard php -r '
$db = new PDO("sqlite:/var/www/app/data/db.sqlite");
$db->exec("VACUUM INTO \"/var/www/app/data/'"$TMP_NAME"'\"");
'

# Pull the snapshot out to the host, then remove the temp copy from the live data dir
# (mirrors vaultwarden's "move the file out of DATA_DIR" step).
docker cp "kanboard:/var/www/app/data/$TMP_NAME" "$DEST/db.sqlite"
docker exec kanboard rm -f "/var/www/app/data/$TMP_NAME"

# Plugins volume (PLUGIN_INSTALLER=true means plugins can be installed at runtime,
# not just baked into the image) -- back it up too so a restore doesn't silently
# drop installed plugins.
docker run --rm --user 1000:1000 -v kanboard_plugins:/plugins:ro -v "$DEST":/dest alpine \
  sh -c 'cd /plugins && tar -czf /dest/plugins.tar.gz . 2>/dev/null || true'

echo "$(date): Backup complete: $DEST"
ls -la "$DEST/"

# Notify Zabbix (trapper item kanboard.backup.ts, unixtime) -- pushes a real epoch
# timestamp, unlike vaultwarden.backup.ts which (kb#158 finding) pushes a formatted
# date STRING into a numeric item and has therefore never recorded a valid value.
if [[ -f "$ZABBIX_TOKEN_FILE" ]]; then
  ZABBIX_TOKEN=$(cat "$ZABBIX_TOKEN_FILE")
  NOW_EPOCH=$(date '+%s')
  env -u HTTPS_PROXY -u HTTP_PROXY -u ALL_PROXY -u https_proxy -u http_proxy -u all_proxy \
    curl -s -X POST "$ZABBIX_URL" \
    -H "Content-Type: application/json" \
    -H "Authorization: Bearer $ZABBIX_TOKEN" \
    -d "{\"jsonrpc\":\"2.0\",\"method\":\"history.push\",\"id\":1,\"params\":{\"itemid\":\"$ZABBIX_ITEM_ID\",\"value\":$NOW_EPOCH}}" > /dev/null \
    && echo "Zabbix notified (kanboard.backup.ts=$NOW_EPOCH)."
else
  echo "WARNING: $ZABBIX_TOKEN_FILE not found -- skipped Zabbix freshness push." >&2
fi

# Rotate: keep last 5 backups
ls -1dt "$BACKUP_DIR"/[0-9]*-[0-9]* 2>/dev/null | tail -n +6 | xargs -r rm -rf
