#!/usr/bin/env bash

set -euo pipefail

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
ENV_FILE="${ENV_FILE:-$ROOT_DIR/.env}"
OUTPUT_FILE=""
COMPRESS=1

if [[ -f "$ENV_FILE" ]]; then
    set -a
    # shellcheck disable=SC1090
    source "$ENV_FILE"
    set +a
fi

usage() {
    cat <<EOF
Usage: $(basename "$0") [--output FILE] [--no-compress]

Exports all AzerothCore databases from the running ac-database container
into a single dump file suitable for migration to another server.

Options:
  --output FILE   Output file path
                  (default: ./backups/YYYY-MM-DD_HH-MM-SS.sql.gz)
  --no-compress   Write plain .sql instead of .sql.gz
  -h, --help      Show this help

Examples:
  $(basename "$0")
  $(basename "$0") --output /mnt/backup/moonwell.sql.gz
  $(basename "$0") --no-compress --output /tmp/dump.sql
EOF
}

log() { printf '[db-export] %s\n' "$*"; }
die() { printf 'ERROR: %s\n' "$*" >&2; exit 1; }

require_running_db() {
    if ! docker compose ps --status running --services 2>/dev/null | grep -qx 'ac-database'; then
        die "ac-database is not running. Start it with: docker compose up -d ac-database"
    fi
}

# ── argument parsing ──────────────────────────────────────────────────────────

while (($#)); do
    case "$1" in
        --output)      OUTPUT_FILE="$2"; shift ;;
        --no-compress) COMPRESS=0 ;;
        -h|--help)     usage; exit 0 ;;
        *) printf 'Unknown option: %s\n\n' "$1" >&2; usage >&2; exit 1 ;;
    esac
    shift
done

# ── main ──────────────────────────────────────────────────────────────────────

cd "$ROOT_DIR"

require_running_db

if [[ -z "$OUTPUT_FILE" ]]; then
    mkdir -p "$ROOT_DIR/backups"
    timestamp="$(date '+%Y-%m-%d_%H-%M-%S')"
    if [[ "$COMPRESS" -eq 1 ]]; then
        OUTPUT_FILE="$ROOT_DIR/backups/${timestamp}.sql.gz"
    else
        OUTPUT_FILE="$ROOT_DIR/backups/${timestamp}.sql"
    fi
fi

mkdir -p "$(dirname "$OUTPUT_FILE")"

log "exporting all databases → $OUTPUT_FILE"
log "this may take a few minutes for large worlds..."

if [[ "$COMPRESS" -eq 1 ]]; then
    docker compose exec -T ac-database bash -lc \
        "mysqldump -uroot -p\"\$MYSQL_ROOT_PASSWORD\" \
         --all-databases \
         --add-drop-database \
         --single-transaction \
         --quick \
         --routines \
         --triggers \
         --events" \
        | gzip -6 > "$OUTPUT_FILE"
else
    docker compose exec -T ac-database bash -lc \
        "mysqldump -uroot -p\"\$MYSQL_ROOT_PASSWORD\" \
         --all-databases \
         --add-drop-database \
         --single-transaction \
         --quick \
         --routines \
         --triggers \
         --events" \
        > "$OUTPUT_FILE"
fi

log "done: $OUTPUT_FILE ($(du -sh "$OUTPUT_FILE" | cut -f1))"
log ""
log "to restore on the new server:"
if [[ "$OUTPUT_FILE" == *.gz ]]; then
    log "  bash scripts/db-import.sh --from $OUTPUT_FILE"
else
    log "  bash scripts/db-import.sh --from $OUTPUT_FILE"
fi