#!/usr/bin/env bash
# Deploy an image tag on the Kvitt Pi (SPEC §10.3, §10.10). Run ON the Pi:   /opt/kvitt/deploy.sh <tag>
#  1. backup first (backup-now.sh: Drive upload confirmed, last-success updated), because a tag may carry a
#     migration and the Pi cannot tell beforehand (the rule "backup before a deploy with a migration" is applied
#     to every deploy); skipped when no database exists yet, or with --skip-backup (rollback while Drive is down)
#  2. sets KVITT_TAG in /opt/kvitt/.env (the previous tag is kept in /opt/kvitt/previous-tag)
#  3. docker compose pull && docker compose up -d, waits for server to be healthy, prints GET /health
# Rollback after a failed migration: /opt/kvitt/deploy.sh "$(cat /opt/kvitt/previous-tag)"; if a migration had
# partially applied, restore the pre-deploy backup (infra/RESTORE.md).
set -euo pipefail
here="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=lib.sh
. "$here/lib.sh"

skip_backup=0
tag=""
for arg in "$@"; do
  case "$arg" in
    --skip-backup) skip_backup=1 ;;
    -h|--help) sed -n '2,10p' "$0"; exit 0 ;;
    -*) die "unknown option $arg" ;;
    *) [[ -z "$tag" ]] || die "usage: $0 <tag> [--skip-backup]"; tag=$arg ;;
  esac
done
[[ -n "$tag" ]] || die "usage: $0 <tag> [--skip-backup]"
[[ "$tag" =~ ^[A-Za-z0-9_][A-Za-z0-9_.-]{0,127}$ ]] || die "not a valid image tag: $tag"
[[ -f "$KVITT_DIR/.env" ]] || die "$KVITT_DIR/.env is missing: run install.sh first"

current=$(env_value KVITT_TAG)
say "Deploying $tag (running: ${current:-none})"

# 1. Backup before the deploy.
if (( skip_backup == 1 )); then
  say "Backup skipped (--skip-backup)"
elif [[ "$(service_health server)" == none ]] || ! compose exec -T backup test -f /data/kvitt.sqlite 2>/dev/null; then
  say "No running server with a database: no backup needed"
else
  "$here/backup-now.sh" || die "the pre-deploy backup failed; nothing deployed (fix the backup, or use --skip-backup knowingly)"
fi

# 2. Tag.
[[ -n "$current" ]] && printf '%s\n' "$current" > "$KVITT_DIR/previous-tag"
env_set KVITT_TAG "$tag"

# 3. Pull and start.
if ! compose pull; then
  [[ -n "$current" ]] && env_set KVITT_TAG "$current"
  die "pull of $tag failed; KVITT_TAG left at ${current:-its old value}"
fi
compose up -d --remove-orphans
if ! wait_healthy server 180; then
  compose logs --tail 50 server || true
  die "server is not healthy on $tag. Roll back: $KVITT_DIR/deploy.sh ${current:-<previous tag>} --skip-backup"
fi
compose ps
print_health || die "server is healthy but /health through Caddy failed (docker compose logs caddy cert-sync)"
say "Deployed $tag."