#!/bin/bash
# ==============================================================================
# WALLARM UNINSTALL SCRIPT - V1.0 (Native deployment)
# ==============================================================================
# Purpose: Safely remove a native (no-Docker) Wallarm filtering node
# Features:
# - Interactive confirmation with safety checks
# - Removes Wallarm NGINX configuration (with backup)
# - Restores disabled default NGINX sites
# - Uninstalls Wallarm packages and repository definitions
# - Removes /opt/wallarm node data
# - Preserves user data and logs (with option to remove)
# - DAU-friendly warnings and confirmations
# ==============================================================================

# Script location and shared library (colors, logging, validation)
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=../common/wallarm-lib.sh
source "$SCRIPT_DIR/../common/wallarm-lib.sh"

# Strict error handling
set -euo pipefail
trap early_error_handler ERR

# ==============================================================================
# CONFIGURATION
# ==============================================================================
CONFIG_GLOB="/etc/nginx/conf.d/wallarm-*.conf"
DEFAULT_BACKUP_GLOB="/etc/nginx/sites-enabled/*.bak"
WALLARM_NODE_DIR="/opt/wallarm"

# ==============================================================================
# FUNCTIONS
# ==============================================================================

# Ask for confirmation
confirm() {
    local prompt="$1"
    local default="${2:-n}"
    local options="[y/N]"

    if [ "$default" = "y" ]; then
        options="[Y/n]"
    fi

    echo -e -n "${YELLOW}${prompt} ${options}${NC} "
    read -r response

    case "$response" in
        [yY][eE][sS]|[yY]) return 0 ;;
        [nN][oO]|[nN])     return 1 ;;
        "")
            if [ "$default" = "y" ]; then
                return 0
            else
                return 1
            fi
            ;;
        *) return 1 ;;
    esac
}

# Detect the package manager in use
detect_package_manager() {
    if command -v apt-get >/dev/null 2>&1; then
        echo "apt"
    elif command -v yum >/dev/null 2>&1; then
        echo "yum"
    elif command -v dnf >/dev/null 2>&1; then
        echo "dnf"
    elif command -v apk >/dev/null 2>&1; then
        echo "apk"
    else
        echo "unknown"
    fi
}

# Remove Wallarm NGINX configuration files
remove_nginx_configs() {
    log_message "INFO" "Looking for Wallarm NGINX configurations..."

    local configs=()
    while IFS= read -r file; do
        configs+=("$file")
    done < <(ls $CONFIG_GLOB 2>/dev/null)

    if [ ${#configs[@]} -eq 0 ]; then
        log_message "INFO" "No Wallarm NGINX configurations found"
        return
    fi

    log_message "INFO" "Found ${#configs[@]} Wallarm NGINX configuration(s)"
    for file in "${configs[@]}"; do
        if confirm "Remove $file? (backup created)" "y"; then
            cp "$file" "$file.uninstall-$(date +%Y%m%d_%H%M%S).bak"
            rm -f "$file"
            log_message "SUCCESS" "Removed $file (backup created)"
        else
            log_message "INFO" "Skipping $file"
        fi
    done
}

# Restore any default NGINX sites we disabled during deployment
restore_default_sites() {
    log_message "INFO" "Looking for disabled default NGINX sites..."

    local restored=0
    while IFS= read -r backup; do
        if [ -f "$backup" ]; then
            local target="${backup%.bak}"
            log_message "INFO" "Restoring $target from $backup"
            if confirm "Restore $target?" "y"; then
                cp "$backup" "$target"
                rm -f "$backup"
                restored=$((restored + 1))
            fi
        fi
    done < <(ls $DEFAULT_BACKUP_GLOB 2>/dev/null)

    if [ "$restored" -gt 0 ]; then
        log_message "SUCCESS" "Restored $restored default site(s)"
    else
        log_message "INFO" "No disabled default sites found"
    fi
}

# Reload NGINX to drop the removed configurations
reload_nginx() {
    log_message "INFO" "Testing and reloading NGINX..."

    if sudo nginx -t 2>/dev/null; then
        sudo systemctl reload nginx 2>/dev/null || sudo nginx -s reload 2>/dev/null || true
        log_message "SUCCESS" "NGINX reloaded"
    else
        log_message "WARNING" "NGINX configuration test failed - reload skipped"
        echo -e "${YELLOW}Run 'sudo nginx -t' manually to diagnose the issue.${NC}"
    fi
}

# Uninstall Wallarm packages via the system package manager
remove_wallarm_packages() {
    local pkg_manager
    pkg_manager=$(detect_package_manager)

    log_message "INFO" "Detected package manager: $pkg_manager"

    if ! confirm "Uninstall Wallarm packages? (wallarm-node, wallarm modules)" "y"; then
        log_message "INFO" "Skipping Wallarm package removal"
        return
    fi

    case "$pkg_manager" in
        "apt")
            log_message "INFO" "Removing Wallarm packages (apt)..."
            sudo apt-get purge -y "wallarm-node" "wallarm-node-nginx" "nginx-module-wallarm*" 2>/dev/null || true
            sudo apt-get autoremove -y 2>/dev/null || true
            ;;
        "yum")
            log_message "INFO" "Removing Wallarm packages (yum)..."
            sudo yum remove -y "wallarm-node" "nginx-module-wallarm*" 2>/dev/null || true
            ;;
        "dnf")
            log_message "INFO" "Removing Wallarm packages (dnf)..."
            sudo dnf remove -y "wallarm-node" "nginx-module-wallarm*" 2>/dev/null || true
            ;;
        "apk")
            log_message "INFO" "Removing Wallarm packages (apk)..."
            sudo apk del "wallarm-node" "nginx-module-wallarm" 2>/dev/null || true
            ;;
        *)
            log_message "WARNING" "Unknown package manager. Please remove Wallarm packages manually."
            echo -e "${YELLOW}Relevant packages usually include: wallarm-node, nginx-module-wallarm${NC}"
            return
            ;;
    esac

    log_message "SUCCESS" "Wallarm packages removed"
}

# Remove Wallarm repository definitions added by the installer
remove_wallarm_repos() {
    log_message "INFO" "Removing Wallarm repository definitions..."

    local removed=0
    while IFS= read -r file; do
        if [ -f "$file" ]; then
            sudo rm -f "$file"
            log_message "SUCCESS" "Removed repo file: $file"
            removed=$((removed + 1))
        fi
    done < <(ls /etc/apt/sources.list.d/*wallarm* /etc/yum.repos.d/*wallarm* 2>/dev/null)

    if [ "$removed" -eq 0 ]; then
        log_message "INFO" "No Wallarm repository files found"
    fi
}

# Remove Wallarm node data directory
remove_wallarm_data() {
    if [ -d "$WALLARM_NODE_DIR" ]; then
        log_message "WARNING" "Found Wallarm data directory: $WALLARM_NODE_DIR"
        log_message "WARNING" "This contains node registration and local data."
        if confirm "Remove $WALLARM_NODE_DIR? (node will need re-registration)" "n"; then
            sudo rm -rf "$WALLARM_NODE_DIR"
            log_message "SUCCESS" "Removed $WALLARM_NODE_DIR"
        else
            log_message "INFO" "Skipping removal of $WALLARM_NODE_DIR"
        fi
    else
        log_message "INFO" "No Wallarm data directory found"
    fi
}

# Remove Wallarm log files (optional)
remove_wallarm_logs() {
    local log_dir="$HOME/logs"
    if [ -d "$log_dir" ]; then
        log_message "INFO" "Found log directory: $log_dir"
        if [ -z "$(ls -A "$log_dir" 2>/dev/null)" ]; then
            log_message "INFO" "Log directory is empty, removing..."
            sudo rmdir "$log_dir" 2>/dev/null || true
        else
            log_message "INFO" "Log directory contains files, preserving..."
        fi
    fi

    if [ -f ".env" ]; then
        if confirm "Remove .env preflight file?" "n"; then
            rm -f ".env"
            log_message "SUCCESS" "Removed .env file"
        fi
    fi
}

# ==============================================================================
# MAIN
# ==============================================================================

main() {
    echo -e "${CYAN}${BOLD}"
    echo "╔══════════════════════════════════════════════════════════════╗"
    echo "║             WALLARM UNINSTALLATION (Native)                  ║"
    echo "╚══════════════════════════════════════════════════════════════╝"
    echo -e "${NC}"

    echo -e "${YELLOW}This script will remove the native Wallarm filtering node.${NC}"
    echo -e "${YELLOW}You will be asked for confirmation before each destructive operation.${NC}"
    echo ""

    if ! confirm "Do you want to continue with the uninstallation?" "n"; then
        log_message "INFO" "Uninstallation cancelled by user"
        exit 0
    fi

    # Step 1: Remove Wallarm NGINX configurations
    echo ""
    echo -e "${CYAN}${BOLD}Step 1: Remove Wallarm NGINX configurations${NC}"
    remove_nginx_configs
    restore_default_sites
    reload_nginx

    # Step 2: Uninstall Wallarm packages
    echo ""
    echo -e "${CYAN}${BOLD}Step 2: Uninstall Wallarm packages${NC}"
    remove_wallarm_packages
    remove_wallarm_repos

    # Step 3: Remove Wallarm data
    echo ""
    echo -e "${CYAN}${BOLD}Step 3: Remove Wallarm data${NC}"
    remove_wallarm_data

    # Step 4: Cleanup
    echo ""
    echo -e "${CYAN}${BOLD}Step 4: Logs and files cleanup${NC}"
    if confirm "Remove Wallarm log files and .env?" "n"; then
        remove_wallarm_logs
    else
        log_message "INFO" "Skipping log/file cleanup"
    fi

    # Final message
    echo ""
    echo -e "${GREEN}${BOLD}╔══════════════════════════════════════════════════════════════╗${NC}"
    echo -e "${GREEN}${BOLD}║               UNINSTALLATION COMPLETE                        ║${NC}"
    echo -e "${GREEN}${BOLD}╚══════════════════════════════════════════════════════════════╝${NC}"
    echo ""
    echo -e "${GREEN}The native Wallarm filtering node has been removed.${NC}"
    echo ""
    echo -e "${YELLOW}Note:${NC}"
    echo -e "  • NGINX itself was kept installed (may be used by other applications)"
    echo -e "  • The Wallarm module may remain in NGINX's modules directory"
    echo -e "  • Wallarm repositories were removed from your package sources"
    echo ""
}

# Run main function
main "$@"