#!/bin/bash
# Health Monitor for Mission Control
# Runs every minute via cron
# Source: https://git.lemonlink.eu/devmatrix/devmatrix-scripts

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
LOG_FILE="/var/log/mission-control/health-monitor.log"
ALERT_COOLDOWN=300  # 5 minutes between alerts
LAST_ALERT_FILE="/tmp/mission-control-last-alert"
HEALTH_URL="http://localhost:3000/api/health"
MAX_RETRIES=3
RETRY_DELAY=5

# Logging
log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $1" | tee -a "$LOG_FILE"
}

# Check if we should send alert (cooldown)
should_alert() {
    if [ -f "$LAST_ALERT_FILE" ]; then
        local last_alert=$(cat "$LAST_ALERT_FILE")
        local current=$(date +%s)
        local diff=$((current - last_alert))
        
        if [ $diff -lt $ALERT_COOLDOWN ]; then
            return 1  # Don't alert yet
        fi
    fi
    return 0  # Can alert
}

# Record alert time
record_alert() {
    date +%s > "$LAST_ALERT_FILE"
}

# Send alert
send_alert() {
    local message="$1"
    
    if ! should_alert; then
        log "Alert cooldown active, skipping notification"
        return
    fi
    
    record_alert
    
    # Log to file
    log "ALERT: $message"
    
    # Telegram notification
    if [ -f "$HOME/.telegram_bot_token" ]; then
        local bot_token=$(cat "$HOME/.telegram_bot_token")
        local chat_id=$(cat "$HOME/.telegram_chat_id" 2>/dev/null || echo "")
        
        if [ -n "$chat_id" ]; then
            curl -s -X POST "https://api.telegram.org/bot$bot_token/sendMessage" \
                -d "chat_id=$chat_id" \
                -d "text=🚨 MISSION CONTROL ALERT%0A%0A$message%0A%0ATime: $(date)" \
                > /dev/null 2>&1 &
        fi
    fi
    
    # System notification
    if command -v notify-send > /dev/null 2>&1; then
        DISPLAY=:0 notify-send -u critical "Mission Control Alert" "$message" 2>/dev/null &
    fi
}

# Health check
health_check() {
    local retries=0
    
    while [ $retries -lt $MAX_RETRIES ]; do
        if curl -sf "$HEALTH_URL" > /dev/null 2>&1; then
            # Health check passed
            if [ -f "/tmp/mission-control-down" ]; then
                rm "/tmp/mission-control-down"
                log "✅ Service recovered and is now healthy"
                send_alert "✅ Mission Control is back online!"
            fi
            return 0
        fi
        
        retries=$((retries + 1))
        if [ $retries -lt $MAX_RETRIES ]; then
            log "Health check failed, retry $retries/$MAX_RETRIES..."
            sleep $RETRY_DELAY
        fi
    done
    
    return 1
}

# Auto-restart service
restart_service() {
    log "Attempting to restart Mission Control..."
    
    # Try PM2 restart first
    if command -v pm2 > /dev/null 2>&1; then
        pm2 reload mission-control
        sleep 10
        
        if health_check; then
            log "✅ Service restarted successfully via PM2"
            send_alert "✅ Mission Control was auto-restarted and is now healthy"
            return 0
        fi
    fi
    
    # Fallback to systemd
    systemctl restart mission-control
    sleep 10
    
    if health_check; then
        log "✅ Service restarted successfully via systemd"
        send_alert "✅ Mission Control was auto-restarted (systemd) and is now healthy"
        return 0
    fi
    
    return 1
}

# Main
main() {
    # Check if service is supposed to be running
    if ! pgrep -f "mission-control" > /dev/null 2>&1; then
        if [ ! -f "/tmp/mission-control-down" ]; then
            log "⚠️ Mission Control is not running!"
            touch "/tmp/mission-control-down"
            send_alert "⚠️ Mission Control is DOWN! Attempting auto-restart..."
            restart_service
        fi
        exit 1
    fi
    
    # Health check
    if ! health_check; then
        if [ ! -f "/tmp/mission-control-down" ]; then
            log "❌ Health check failed after $MAX_RETRIES retries"
            touch "/tmp/mission-control-down"
            send_alert "❌ Mission Control health check FAILED! Status: Unhealthy"
            restart_service
        fi
        exit 1
    fi
    
    exit 0
}

main "$@"