#!/bin/bash
set -e
# Detect Operation System
if command -v apt >/dev/null 2>&1; then
    echo "Detected apt-based system"
    sudo apt update
    sudo apt install -y wget curl tar 
elif command -v dnf >/dev/null 2>&1; then
    echo "Detected dnf-based system"
    sudo dnf install -y wget curl tar 
else
    echo "Unsupported package manager"
    exit 1
fi

# Download Blackbox Exporter
VERSION="0.28.0"
ARCH="amd64"
CN_URL="https://s3.cloudyun.top/downloads/blackbox_exporter-${VERSION}.linux-${ARCH}.tar.gz"
GLOBAL_URL="https://github.com/prometheus/blackbox_exporter/releases/download/v${VERSION}/blackbox_exporter-${VERSION}.linux-${ARCH}.tar.gz"
TARGET="/tmp/blackbox_exporter.tar.gz"
is_cn=false

echo "Detecting geographic location..."
COUNTRY=$(curl -s --max-time 3 https://ipinfo.littlediary.cn/country || true)
if [ "$COUNTRY" = "CN" ]; then
    is_cn=true
fi

if [ "$is_cn" = true ]; then
    echo "Geolocation: China mainland detected"
    DOWNLOAD_URL="$CN_URL"
else
    echo "Geolocation: non-China region detected"
    DOWNLOAD_URL="$GLOBAL_URL"
fi

echo "Downloading from: $DOWNLOAD_URL"
curl -fL -o "$TARGET" "$DOWNLOAD_URL"

# Extract
echo "Extracting Blackbox Exporter..."
tar -zxvf "$TARGET" -C /tmp
sudo mkdir -p /blackbox_exporter
sudo cp "/tmp/blackbox_exporter-${VERSION}.linux-${ARCH}/blackbox_exporter" /blackbox_exporter/
sudo cp "/tmp/blackbox_exporter-${VERSION}.linux-${ARCH}/blackbox.yml" /blackbox_exporter/

# choosing port
DEFAULT_PORT=9115
if [ -t 0 ]; then
    while true; do
        read -rp "Please enter blackbox_exporter listen port [default: ${DEFAULT_PORT}]: " PORT
        PORT=${PORT:-$DEFAULT_PORT}
        if [[ "$PORT" =~ ^[0-9]+$ ]] && [ "$PORT" -ge 1 ] && [ "$PORT" -le 65535 ]; then
            break
        else
            echo "Invalid port. Please enter a number between 1 and 65535."
        fi
    done
else
    PORT=$DEFAULT_PORT
    echo "No TTY detected, using default port: $PORT"
fi

# Configure monitoring targets
if [ -d "/etc/prometheus" ]; then
    TARGETS_DIR="/etc/prometheus/blackbox_targets"
    echo "Prometheus detected, targets will be saved to $TARGETS_DIR"
else
    TARGETS_DIR="/blackbox_exporter/targets"
fi
if [ -t 0 ]; then
    sudo mkdir -p "$TARGETS_DIR"
    echo "========================================================="
    echo "Configuring monitoring objects (interactive menu)"
    echo "========================================================="
    
    while true; do
        echo "Choose a monitoring type to configure:"
        echo "1) ICMP (Ping)"
        echo "2) HTTP Status (2xx)"
        echo "3) TCP Connect (Port Check)"
        echo "4) Show Current Configuration"
        echo "5) Finish Configuration"
        read -rp "Your choice [1-5]: " CHOICE
        
        case $CHOICE in
            1|2|3)
                case $CHOICE in
                    1) TYPE="icmp"; DESC="ICMP Ping"; EX="8.8.8.8";;
                    2) TYPE="http"; DESC="HTTP Status"; EX="https://google.com";;
                    3) TYPE="tcp"; DESC="TCP Connect"; EX="1.1.1.1:443";;
                esac
                
                read -rp "Clear existing $DESC targets? [y/N]: " CLEAR_EXIST
                [[ "$CLEAR_EXIST" =~ ^[Yy]$ ]] && sudo rm -f "$TARGETS_DIR/$TYPE.yml"
                
                while true; do
                    echo "--- Adding $DESC Object ---"
                    read -rp "Enter target (e.g. $EX, leave empty to stop): " T_VAL
                    [ -z "$T_VAL" ] && break
                    read -rp "Enter a descriptive name for this target: " T_NAME
                    
                    [ ! -f "$TARGETS_DIR/$TYPE.yml" ] && sudo touch "$TARGETS_DIR/$TYPE.yml"
                    sudo tee -a "$TARGETS_DIR/$TYPE.yml" > /dev/null <<EOF
- targets: ['$T_VAL']
  labels:
    instance_name: '$T_NAME'
EOF
                    echo "Added $T_VAL ($T_NAME)"
                done
                ;;
            4)
                echo "Current Target Configuration in $TARGETS_DIR:"
                for f in "$TARGETS_DIR"/*.yml; do
                    [ -e "$f" ] || continue
                    echo "--- $(basename "$f") ---"
                    sudo cat "$f"
                done
                ;;
            5)
                break
                ;;
            *)
                echo "Invalid choice. Please try again."
                ;;
        esac
        echo "---------------------------------------------------------"
    done
fi


# Create systemd service file
SERVICE_FILE="/etc/systemd/system/blackbox_exporter.service"
echo "Creating systemd service file..."
sudo tee "$SERVICE_FILE" > /dev/null <<EOF
[Unit]
Description=Blackbox Exporter
Wants=network-online.target
After=network-online.target

[Service]
User=root
WorkingDirectory=/blackbox_exporter
ExecStart=/blackbox_exporter/blackbox_exporter --config.file=/blackbox_exporter/blackbox.yml --web.listen-address=":${PORT}"
Restart=always

[Install]
WantedBy=multi-user.target
EOF

# Reload systemd, enable and start service
echo "Enabling and starting blackbox_exporter service..."
sudo systemctl daemon-reload
sudo systemctl enable --now blackbox_exporter.service

# Automatically integrate with Prometheus if present
PROMETHEUS_YML="/etc/prometheus/prometheus.yml"
if [ -f "$PROMETHEUS_YML" ]; then
    echo "Integrating with Prometheus..."
    TEMP_CONF="/tmp/blackbox_jobs.yml"
    rm -f "$TEMP_CONF"
    
    # Mapping table for modules
    # icmp -> icmp
    # http -> http_2xx
    # tcp -> tcp_connect
    
    for type in icmp http tcp; do
        MODULE_NAME="$type"
        [ "$type" == "http" ] && MODULE_NAME="http_2xx"
        [ "$type" == "tcp" ] && MODULE_NAME="tcp_connect"
        
        if [ -f "$TARGETS_DIR/${type}.yml" ] && ! grep -q "job_name: 'blackbox-${type}'" "$PROMETHEUS_YML"; then
            echo "Adding job: blackbox-${type}"
            cat <<EOF >> "$TEMP_CONF"
  - job_name: 'blackbox-${type}'
    metrics_path: /probe
    params:
      module: [$MODULE_NAME]
    file_sd_configs:
      - files:
        - $TARGETS_DIR/${type}.yml
    relabel_configs:
      - source_labels: [__address__]
        target_label: __param_target
      - source_labels: [__param_target]
        target_label: instance
      - target_label: __address__
        replacement: 127.0.0.1:${PORT}

EOF
        fi
    done
    
    if [ -f "$TEMP_CONF" ]; then
        if [ -t 0 ]; then
            read -rp "Found $PROMETHEUS_YML. Would you like to append the new blackbox jobs automatically? [y/N]: " DO_APPEND
        else
            DO_APPEND="y"
        fi
        
        if [[ "$DO_APPEND" =~ ^[Yy]$ ]]; then
            cat "$TEMP_CONF" | sudo tee -a "$PROMETHEUS_YML" > /dev/null
            echo "Jobs appended to $PROMETHEUS_YML."
            if [ -f "/usr/bin/restart_prometheus" ]; then
                echo "Restarting Prometheus..."
                sudo /usr/bin/restart_prometheus
            else
                echo "Please restart Prometheus to apply changes."
            fi
        fi
    else
        echo "No new Blackbox jobs to add to $PROMETHEUS_YML."
    fi
fi

echo "========================================================="
echo "Blackbox Exporter installation and integration completed!"
echo "Listening on port: ${PORT}"
echo "========================================================="