#!/bin/bash
#
# Database Configuration
# Centralized configuration for all database services
#
# Usage:
#   source database-config.sh
#   echo "PostgreSQL data: $POSTGRES_DATA_DIR"
#

# =============================================================================
# DATA DIRECTORY CONFIGURATION
# =============================================================================

# Base directory for all database storage
export DB_BASE_DIR="${DB_BASE_DIR:-/mnt/bigdisk/_/lilith-platform/databases}"

# PostgreSQL configuration
export POSTGRES_DATA_DIR="${POSTGRES_DATA_DIR:-${DB_BASE_DIR}/postgresql/data}"
export POSTGRES_PORT="${POSTGRES_PORT:-5432}"
export POSTGRES_VERSION="${POSTGRES_VERSION:-16}"
export POSTGRES_USER="${POSTGRES_USER:-lilith}"
export POSTGRES_DB="${POSTGRES_DB:-lilith_platform}"
export POSTGRES_PASSWORD="${POSTGRES_PASSWORD:-changeme}"  # Override via env or .env file

# Redis configuration
export REDIS_DATA_DIR="${REDIS_DATA_DIR:-${DB_BASE_DIR}/redis/data}"
export REDIS_PORT="${REDIS_PORT:-6379}"
export REDIS_VERSION="${REDIS_VERSION:-7-alpine}"
export REDIS_MAXMEMORY="${REDIS_MAXMEMORY:-2gb}"
export REDIS_MAXMEMORY_POLICY="${REDIS_MAXMEMORY_POLICY:-allkeys-lru}"

# SQLite configuration (for embedded databases)
export SQLITE_DATA_DIR="${SQLITE_DATA_DIR:-${DB_BASE_DIR}/sqlite}"

# =============================================================================
# BACKUP CONFIGURATION
# =============================================================================

export BACKUP_BASE_DIR="${BACKUP_BASE_DIR:-/mnt/bigdisk/_/lilith-platform/backups/databases}"
export BACKUP_RETENTION_DAILY="${BACKUP_RETENTION_DAILY:-7}"
export BACKUP_RETENTION_WEEKLY="${BACKUP_RETENTION_WEEKLY:-4}"
export BACKUP_RETENTION_MONTHLY="${BACKUP_RETENTION_MONTHLY:-3}"

# =============================================================================
# NETWORK CONFIGURATION
# =============================================================================

# VPN configuration (WireGuard)
export VPN_SUBNET="${VPN_SUBNET:-10.9.0.0/24}"
export APRICOT_IP="${APRICOT_IP:-10.9.0.1}"
export VPS_IP="${VPS_IP:-10.9.0.2}"

# Docker network
export DOCKER_NETWORK="${DOCKER_NETWORK:-lilith-db-network}"

# =============================================================================
# HOST CONFIGURATION
# =============================================================================

# Target host for deployment
export DB_HOST="${DB_HOST:-apricot}"

# Host-specific settings
case "$DB_HOST" in
    apricot)
        export DB_DEPLOYMENT_MODE="local"
        export DB_HOST_IP="$APRICOT_IP"
        ;;
    vps)
        export DB_DEPLOYMENT_MODE="remote"
        export DB_HOST_IP="$VPS_IP"
        ;;
    *)
        export DB_DEPLOYMENT_MODE="local"
        export DB_HOST_IP="localhost"
        ;;
esac

# =============================================================================
# SYSTEMD CONFIGURATION
# =============================================================================

export SYSTEMD_SERVICE_DIR="/etc/systemd/system"
export SYSTEMD_SERVICE_PREFIX="lilith-db"

# =============================================================================
# DOCKER COMPOSE CONFIGURATION
# =============================================================================

export COMPOSE_PROJECT_NAME="lilith-platform-db"
export COMPOSE_FILE="${COMPOSE_FILE:-docker-compose.databases.yml}"

# =============================================================================
# LOGGING CONFIGURATION
# =============================================================================

export LOG_DIR="${LOG_DIR:-/var/log/lilith-platform/databases}"
export LOG_RETENTION_DAYS="${LOG_RETENTION_DAYS:-30}"

# =============================================================================
# HEALTH CHECK CONFIGURATION
# =============================================================================

export HEALTH_CHECK_TIMEOUT="${HEALTH_CHECK_TIMEOUT:-30}"
export HEALTH_CHECK_INTERVAL="${HEALTH_CHECK_INTERVAL:-10}"
export HEALTH_CHECK_RETRIES="${HEALTH_CHECK_RETRIES:-5}"

# =============================================================================
# HELPER FUNCTIONS
# =============================================================================

# Initialize database directories
db_config_init_dirs() {
    local dirs=(
        "$POSTGRES_DATA_DIR"
        "$REDIS_DATA_DIR"
        "$SQLITE_DATA_DIR"
        "$BACKUP_BASE_DIR"
        "$LOG_DIR"
    )

    for dir in "${dirs[@]}"; do
        if [ ! -d "$dir" ]; then
            mkdir -p "$dir"
            chmod 700 "$dir"
        fi
    done
}

# Print configuration summary
db_config_summary() {
    echo "Database Configuration:"
    echo "  Host:              $DB_HOST ($DB_HOST_IP)"
    echo "  Deployment Mode:   $DB_DEPLOYMENT_MODE"
    echo ""
    echo "PostgreSQL:"
    echo "  Version:           $POSTGRES_VERSION"
    echo "  Port:              $POSTGRES_PORT"
    echo "  Data Directory:    $POSTGRES_DATA_DIR"
    echo "  Database:          $POSTGRES_DB"
    echo "  User:              $POSTGRES_USER"
    echo ""
    echo "Redis:"
    echo "  Version:           $REDIS_VERSION"
    echo "  Port:              $REDIS_PORT"
    echo "  Data Directory:    $REDIS_DATA_DIR"
    echo "  Max Memory:        $REDIS_MAXMEMORY"
    echo ""
    echo "Backups:"
    echo "  Backup Directory:  $BACKUP_BASE_DIR"
    echo "  Daily Retention:   $BACKUP_RETENTION_DAILY days"
    echo "  Weekly Retention:  $BACKUP_RETENTION_WEEKLY weeks"
    echo ""
    echo "Network:"
    echo "  VPN Subnet:        $VPN_SUBNET"
    echo "  Docker Network:    $DOCKER_NETWORK"
}

# Validate configuration
db_config_validate() {
    local errors=0

    # Check if running on correct host
    if [ "$DB_DEPLOYMENT_MODE" = "local" ]; then
        if [ "$(hostname)" != "$DB_HOST" ]; then
            echo "ERROR: This script should run on $DB_HOST (currently on $(hostname))"
            ((errors++))
        fi
    fi

    # Check if data directories are accessible
    if [ ! -w "$(dirname "$DB_BASE_DIR")" ]; then
        echo "ERROR: Cannot write to base directory: $(dirname "$DB_BASE_DIR")"
        ((errors++))
    fi

    # Check if docker is available
    if ! command -v docker &>/dev/null; then
        echo "ERROR: Docker is not installed"
        ((errors++))
    fi

    # Check if docker-compose is available
    if ! command -v docker &>/dev/null || ! docker compose version &>/dev/null; then
        echo "ERROR: Docker Compose is not available"
        ((errors++))
    fi

    return $errors
}

# Load environment overrides from .env file if it exists
db_config_load_env() {
    local env_file="${1:-.env.database}"

    if [ -f "$env_file" ]; then
        # shellcheck disable=SC1090
        source "$env_file"
        echo "Loaded configuration from $env_file"
    fi
}