#!/usr/bin/env bash
# Initialise the XAMXAM SQLite database from schema.sql, then run incremental migrations.
# Safe to run on existing databases — schema uses IF NOT EXISTS / INSERT OR IGNORE.
# Usage:
#   scripts/migrate.sh              # xamxam.db (default)
#
# Before any schema/migration is applied, a WAL-safe snapshot of the database is
# written (via sqlite3 .backup) so a deploy is always recoverable if a migration
# goes wrong. This augments the hourly cron backups with a pre-deploy checkpoint.

set -euo pipefail

REPO_ROOT="${REPO_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"

# Detect layout: local dev has app/ subdir, server has files at repo root
if [ -d "$REPO_ROOT/app/storage" ]; then
    SCHEMA="$REPO_ROOT/app/storage/schema.sql"
    PROD_DB="$REPO_ROOT/app/storage/xamxam.db"
    MIGRATIONS="$REPO_ROOT/app/migrations/run.php"
    # Local dev DB is disposable — no pre-migration backup needed here.
    BACKUP_DIR=""
elif [ -f "$REPO_ROOT/storage/schema.sql" ]; then
    SCHEMA="$REPO_ROOT/storage/schema.sql"
    PROD_DB="$REPO_ROOT/storage/xamxam.db"
    MIGRATIONS="$REPO_ROOT/migrations/run.php"
    BACKUP_DIR="/var/backups/xamxam"
else
    echo "ERROR: cannot find storage/schema.sql" >&2
    exit 1
fi

# ── Pre-migration backup (production remote only) ───────────────────────────
backup_before_migrate() {
    [ -n "$BACKUP_DIR" ] || return 0
    [ -f "$PROD_DB" ] || return 0
    command -v sqlite3 >/dev/null 2>&1 || { echo "  [backup] sqlite3 not found — skipping"; return 0; }
    command -v gzip    >/dev/null 2>&1 || { echo "  [backup] gzip not found — skipping"; return 0; }

    if ! mkdir -p "$BACKUP_DIR" 2>/dev/null; then
        echo "  [backup] WARNING: cannot write to $BACKUP_DIR — skipping pre-deploy backup" >&2
        return 0
    fi

    local snapshot
    snapshot="/tmp/xamxam-predeploy-$$.db"
    if sqlite3 "$PROD_DB" ".backup '$snapshot'" 2>/dev/null; then
        local out
        out="$BACKUP_DIR/db-$(date +%Y-%m-%dT%H-%M-%S).db.gz"
        gzip -c "$snapshot" > "$out"
        rm -f "$snapshot"
        echo "  [backup] pre-deploy snapshot: $out"
    else
        rm -f "$snapshot"
        echo "  [backup] WARNING: sqlite3 .backup failed — continuing without a pre-deploy snapshot" >&2
    fi
}

if [ -n "$BACKUP_DIR" ]; then
    echo "──────────────────────────────────────────────"
    echo "  [backup] taking pre-migration snapshot…"
    backup_before_migrate
fi

echo "──────────────────────────────────────────────"
echo "  [schema] applying schema…"
if command -v syntaqlite &>/dev/null; then
    syntaqlite analyze "$SCHEMA" || { echo "ERROR: schema.sql validation failed" >&2; exit 1; }
fi
sqlite3 "$PROD_DB" < "$SCHEMA"
echo "  [schema] done"

if [ -f "$MIGRATIONS" ]; then
    echo "──────────────────────────────────────────────"
    php "$MIGRATIONS" "$PROD_DB"
else
    echo "  [migrations] run.php not found — skipping"
fi