#!/usr/bin/env bash
# ==============================================================================
# Static Web (nginx) Deployment Script — Multi-Instance
# ==============================================================================
# Deploys an nginx container serving static files behind Traefik.
# Each instance is identified by --dir. Multiple instances can coexist.
#
# Usage:  deploy-docker-web.sh --domain web1.an2.io --dir acme
#         deploy-docker-web.sh --domain web2.an2.io --dir acme-dev
#         deploy-docker-web.sh --remove --dir acme [--purge] [--yes]
# ==============================================================================

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
source "${SCRIPT_DIR}/common.sh"

# --- Parse arguments ---
parse_args "$@"

# --- Validate --dir ---
[[ -n "$ARG_DIR" ]] || fatal "--dir is required. Example: $0 --domain web.an2.io --dir mysite"

if ! [[ "$ARG_DIR" =~ ^[a-zA-Z0-9][a-zA-Z0-9_-]*$ ]]; then
    fatal "--dir value must be alphanumeric (hyphens/underscores ok, no spaces/slashes): ${ARG_DIR}"
fi

# --- Derive names from --dir ---
DIR_NAME="$ARG_DIR"
SERVICE_NAME="web-${DIR_NAME}"
BASE_DIR="/opt/${DIR_NAME}"
CONFIG_NAME="web-${DIR_NAME}"
UNIT_NAME="web-${DIR_NAME}-docker"
CONTAINER_NAME="web-${DIR_NAME}"

# --- Handle --remove ---
if [[ "$ARG_REMOVE" == "1" ]]; then
    require_root
    do_remove "$SERVICE_NAME" "$CONFIG_NAME" "$UNIT_NAME" "$BASE_DIR"
    exit 0
fi

# --- Validate --domain (required for deploy) ---
if [[ -z "$ARG_DOMAIN" ]] && ! [[ -f "${BASE_DIR}/.env" ]]; then
    fatal "--domain is required for deploy. Example: $0 --domain web.an2.io --dir ${DIR_NAME}"
fi

# --- Domain resolution ---
if [[ -n "$ARG_DOMAIN" ]]; then
    DOMAIN="$ARG_DOMAIN"
elif [[ -f "${BASE_DIR}/.env" ]] && grep -q '^DOMAIN=' "${BASE_DIR}/.env"; then
    DOMAIN="$(grep '^DOMAIN=' "${BASE_DIR}/.env" | cut -d= -f2)"
else
    fatal "--domain is required for deploy."
fi

# --- Detect current state for banner ---
traefik_status="Not found — will deploy"
if docker ps --format '{{.Names}}' 2>/dev/null | grep -q '^traefik$'; then
    traefik_status="Running"
elif [[ -f "${TRAEFIK_DIR}/docker-compose.yml" ]]; then
    traefik_status="Stopped — will start"
fi

install_mode="Fresh install"
if [[ -f "${BASE_DIR}/.env" ]]; then
    install_mode="Re-run (preserving data)"
fi

# --- Print deployment plan ---
echo ""
echo -e "${CYAN}══════════════════════════════════════════════${NC}"
echo -e "${CYAN}  Deploying Web: ${DIR_NAME} (Docker/nginx)${NC}"
echo -e "${CYAN}══════════════════════════════════════════════${NC}"
echo -e "  Domain:      ${DOMAIN}"
echo -e "  Data:        ${BASE_DIR}/html/"
echo -e "  Container:   ${CONTAINER_NAME}"
echo -e "  Traefik:     ${traefik_status}"
echo -e "  Mode:        ${install_mode}"
echo -e "${CYAN}══════════════════════════════════════════════${NC}"
echo ""

# --- Check if already deployed and running ---
if [[ -f "${BASE_DIR}/docker-compose.yml" ]] && \
   docker ps --format '{{.Names}}' 2>/dev/null | grep -q "^${CONTAINER_NAME}$"; then
    echo -e "${GREEN}  ${CONTAINER_NAME} is already running — nothing to do.${NC}"
    echo ""
    echo -e "  Document root: ${BASE_DIR}/html/"
    echo -e "  Backup:        ${SCRIPT_DIR}/backup-web.sh --dir ${DIR_NAME}"
    echo -e "  Remove:        $0 --remove --dir ${DIR_NAME} [--purge]"
    echo ""
    exit 0
fi

# --- Shared infrastructure ---
require_root
detect_os
install_prerequisites
ensure_docker_network
ensure_traefik
configure_firewall

# --- Backup restore check ---
if check_and_restore_backup "$DIR_NAME"; then
    saved_domain="$DOMAIN"
    # shellcheck source=/dev/null
    source "${BASE_DIR}/.env"
    DOMAIN="$saved_domain"
else
    # --- Fresh install ---

    if [[ -f "${BASE_DIR}/.env" ]]; then
        saved_domain="$DOMAIN"
        # shellcheck source=/dev/null
        source "${BASE_DIR}/.env"
        DOMAIN="$saved_domain"
    fi

    mkdir -p "${BASE_DIR}/html"

    # Default placeholder page
    if [[ ! -f "${BASE_DIR}/html/index.html" ]]; then
        cat > "${BASE_DIR}/html/index.html" <<HTML
<!DOCTYPE html>
<html lang="en">
<head><meta charset="utf-8"><title>${DOMAIN}</title></head>
<body><h1>${DOMAIN}</h1><p>Replace this file at ${BASE_DIR}/html/index.html</p></body>
</html>
HTML
    fi

    # --- Generate .env ---
    cat > "${BASE_DIR}/.env" <<DOTENV
# Generated by deploy-docker-web.sh on $(date -Iseconds)
DOMAIN=${DOMAIN}
DIR_NAME=${DIR_NAME}
DOTENV
    chmod 600 "${BASE_DIR}/.env"
    ok ".env written."

    # --- Generate docker-compose.yml ---
    cat > "${BASE_DIR}/docker-compose.yml" <<COMPOSE
services:
  web:
    image: nginx:alpine
    container_name: ${CONTAINER_NAME}
    restart: unless-stopped
    security_opt:
      - no-new-privileges:true
    mem_limit: 512M
    read_only: true
    tmpfs:
      - /var/cache/nginx
      - /var/run
      - /tmp
    volumes:
      - ./html:/usr/share/nginx/html:ro
    networks:
      - traefik-public
    logging:
      driver: json-file
      options:
        max-size: "50m"
        max-file: "5"

networks:
  traefik-public:
    external: true
COMPOSE
    ok "docker-compose.yml written."
fi

# --- Always do these (fresh or restored) ---
write_traefik_dynamic_config "$CONFIG_NAME" "$DOMAIN" "http://${CONTAINER_NAME}:80"
install_systemd_unit "$UNIT_NAME" "$BASE_DIR"
(cd "$BASE_DIR" && docker compose up -d)
wait_for_healthy "$CONTAINER_NAME" "http://localhost:80/" 60

# --- Summary ---
echo ""
echo -e "${GREEN}══════════════════════════════════════════════${NC}"
echo -e "${GREEN}  Web (${DIR_NAME}) deployed successfully${NC}"
echo -e "${GREEN}══════════════════════════════════════════════${NC}"
echo -e "  URL:         https://${DOMAIN}"
echo -e "  Doc root:    ${BASE_DIR}/html/"
echo -e "  Traefik:     ${TRAEFIK_DYNAMIC_DIR}/${CONFIG_NAME}.yml"
echo -e "  Systemd:     systemctl status ${UNIT_NAME}"
echo -e "  Logs:        docker logs -f ${CONTAINER_NAME}"
echo -e "${GREEN}══════════════════════════════════════════════${NC}"
echo ""