#!/bin/bash
#
# Payload CMS - Backup-System Setup
# Richtet das automatische Backup-System auf einem neuen Server ein.
#
# Verwendung:
#   ./setup-backup.sh
#
# Voraussetzungen:
#   - PostgreSQL-Client (psql, pg_dump) installiert
#   - Zugriff auf die Datenbank
#

set -euo pipefail

# ============================================================================
# Konfiguration
# ============================================================================

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
BACKUP_DIR="/home/payload/backups/postgres"
LOG_DIR="/home/payload/logs"

# ============================================================================
# Funktionen
# ============================================================================

print_header() {
    echo ""
    echo "=============================================="
    echo "  Payload CMS - Backup-System Setup"
    echo "=============================================="
    echo ""
}

print_step() {
    echo "[$(date '+%H:%M:%S')] $1"
}

print_success() {
    echo "[✓] $1"
}

print_error() {
    echo "[✗] ERROR: $1" >&2
}

check_prerequisites() {
    print_step "Prüfe Voraussetzungen..."

    if ! command -v psql &> /dev/null; then
        print_error "psql nicht gefunden. Installiere mit: apt install postgresql-client"
        exit 1
    fi

    if ! command -v pg_dump &> /dev/null; then
        print_error "pg_dump nicht gefunden. Installiere mit: apt install postgresql-client"
        exit 1
    fi

    print_success "PostgreSQL-Client verfügbar"
}

setup_directories() {
    print_step "Erstelle Verzeichnisse..."

    mkdir -p "$BACKUP_DIR"
    mkdir -p "$LOG_DIR"

    print_success "Verzeichnisse erstellt"
}

setup_pgpass() {
    local pgpass_file="$HOME/.pgpass"

    print_step "Konfiguriere PostgreSQL-Authentifizierung..."

    if [[ -f "$pgpass_file" ]]; then
        echo "  .pgpass existiert bereits."
        read -p "  Überschreiben? [y/N] " -n 1 -r
        echo
        if [[ ! $REPLY =~ ^[Yy]$ ]]; then
            print_success ".pgpass beibehalten"
            return 0
        fi
    fi

    echo ""
    echo "  PostgreSQL-Verbindungsdaten eingeben:"
    read -p "  Host [10.10.181.101]: " db_host
    db_host=${db_host:-10.10.181.101}

    read -p "  Port [5432]: " db_port
    db_port=${db_port:-5432}

    read -p "  Datenbank [payload_db]: " db_name
    db_name=${db_name:-payload_db}

    read -p "  Benutzer [payload]: " db_user
    db_user=${db_user:-payload}

    read -sp "  Passwort: " db_pass
    echo ""

    if [[ -z "$db_pass" ]]; then
        print_error "Passwort darf nicht leer sein"
        exit 1
    fi

    echo "${db_host}:${db_port}:${db_name}:${db_user}:${db_pass}" > "$pgpass_file"
    chmod 600 "$pgpass_file"

    print_success ".pgpass erstellt (chmod 600)"

    # Test connection
    print_step "Teste Datenbankverbindung..."
    if psql -h "$db_host" -p "$db_port" -U "$db_user" -d "$db_name" -c "SELECT 1" > /dev/null 2>&1; then
        print_success "Datenbankverbindung erfolgreich"
    else
        print_error "Datenbankverbindung fehlgeschlagen"
        exit 1
    fi
}

setup_s3() {
    local s3cfg_file="$HOME/.s3cfg"

    print_step "Konfiguriere S3 Offsite-Backup..."

    read -p "  S3 Offsite-Backup aktivieren? [Y/n] " -n 1 -r
    echo
    if [[ $REPLY =~ ^[Nn]$ ]]; then
        print_success "S3-Backup übersprungen"
        return 0
    fi

    # Check if s3cmd is installed
    if ! command -v s3cmd &> /dev/null; then
        echo "  s3cmd nicht gefunden. Installiere..."
        if command -v apt &> /dev/null; then
            sudo apt update && sudo apt install -y s3cmd
        else
            print_error "Bitte s3cmd manuell installieren"
            return 1
        fi
    fi

    if [[ -f "$s3cfg_file" ]]; then
        echo "  .s3cfg existiert bereits."
        read -p "  Überschreiben? [y/N] " -n 1 -r
        echo
        if [[ ! $REPLY =~ ^[Yy]$ ]]; then
            print_success ".s3cfg beibehalten"
            return 0
        fi
    fi

    echo ""
    echo "  S3-Verbindungsdaten eingeben:"
    read -p "  S3 Host (z.B. fsn1.your-objectstorage.com): " s3_host

    if [[ -z "$s3_host" ]]; then
        print_error "S3 Host darf nicht leer sein"
        return 1
    fi

    read -p "  Access Key: " s3_access_key
    read -sp "  Secret Key: " s3_secret_key
    echo ""

    if [[ -z "$s3_access_key" || -z "$s3_secret_key" ]]; then
        print_error "Access Key und Secret Key dürfen nicht leer sein"
        return 1
    fi

    cat > "$s3cfg_file" << EOF
[default]
access_key = ${s3_access_key}
secret_key = ${s3_secret_key}
host_base = ${s3_host}
host_bucket = %(bucket)s.${s3_host}
use_https = True
signature_v2 = False
EOF
    chmod 600 "$s3cfg_file"

    print_success ".s3cfg erstellt (chmod 600)"

    # Test S3 connection
    print_step "Teste S3-Verbindung..."
    if s3cmd ls > /dev/null 2>&1; then
        print_success "S3-Verbindung erfolgreich"
        s3cmd ls
    else
        print_error "S3-Verbindung fehlgeschlagen"
        return 1
    fi
}

install_backup_script() {
    print_step "Installiere Backup-Skript..."

    local source_script="${SCRIPT_DIR}/backup-db.sh"
    local target_script="${BACKUP_DIR}/backup-db.sh"

    if [[ ! -f "$source_script" ]]; then
        print_error "Backup-Skript nicht gefunden: $source_script"
        exit 1
    fi

    cp "$source_script" "$target_script"
    chmod +x "$target_script"

    print_success "Backup-Skript installiert: $target_script"
}

setup_cron() {
    print_step "Konfiguriere Cron-Job..."

    local cron_entry="0 3 * * * ${BACKUP_DIR}/backup-db.sh >> ${LOG_DIR}/backup-cron.log 2>&1"

    # Check if cron entry already exists
    if crontab -l 2>/dev/null | grep -q "backup-db.sh"; then
        echo "  Cron-Job existiert bereits."
        read -p "  Überschreiben? [y/N] " -n 1 -r
        echo
        if [[ ! $REPLY =~ ^[Yy]$ ]]; then
            print_success "Cron-Job beibehalten"
            return 0
        fi
        # Remove existing entry
        crontab -l 2>/dev/null | grep -v "backup-db.sh" | crontab -
    fi

    # Add new cron entry
    (crontab -l 2>/dev/null; echo "# Payload CMS - Tägliches PostgreSQL Backup"; echo "$cron_entry") | crontab -

    print_success "Cron-Job eingerichtet (täglich um 03:00 Uhr)"
}

test_backup() {
    print_step "Teste Backup..."

    read -p "  Test-Backup jetzt ausführen? [Y/n] " -n 1 -r
    echo
    if [[ $REPLY =~ ^[Nn]$ ]]; then
        print_success "Test übersprungen"
        return 0
    fi

    if "${BACKUP_DIR}/backup-db.sh" --verbose; then
        print_success "Test-Backup erfolgreich"
    else
        print_error "Test-Backup fehlgeschlagen"
        exit 1
    fi
}

print_summary() {
    echo ""
    echo "=============================================="
    echo "  Setup abgeschlossen!"
    echo "=============================================="
    echo ""
    echo "  Backup-Skript: ${BACKUP_DIR}/backup-db.sh"
    echo "  Lokale Backups: ${BACKUP_DIR}/"
    echo "  Log-Dateien: ${BACKUP_DIR}/backup.log"
    echo "                ${LOG_DIR}/backup-cron.log"
    echo ""
    echo "  Cron-Job: Täglich um 03:00 Uhr"
    echo ""
    echo "  Manuelle Ausführung:"
    echo "    ${BACKUP_DIR}/backup-db.sh --verbose"
    echo ""
}

# ============================================================================
# Hauptprogramm
# ============================================================================

main() {
    print_header
    check_prerequisites
    setup_directories
    setup_pgpass
    setup_s3
    install_backup_script
    setup_cron
    test_backup
    print_summary
}

main "$@"