#!/bin/bash

HOSTNAME=$(hostname)
DATE=$(date '+%Y-%m-%d %H:%M:%S')
VM_ID=107
LOG_FILE="/var/log/vm107-monitor.log"
STATE_FILE="/var/run/vm107-last-state"

check_vm_status() {
    local vm_status=$(qm status $VM_ID 2>/dev/null | grep -oP 'status: \K.*')
    
    if [ -z "$vm_status" ]; then
        echo "ERROR:VM_NOT_FOUND"
        return 1
    fi
    
    if [ "$vm_status" = "running" ]; then
        if ps aux | grep -E "(kvm|qemu).*-id $VM_ID" | grep -qv grep; then
            echo "RUNNING:OK"
            return 0
        else
            echo "ERROR:PROCESS_MISSING"
            return 1
        fi
    elif [ "$vm_status" = "stopped" ]; then
        echo "STOPPED:VM_STOPPED"
        return 1
    elif [ "$vm_status" = "internal-error" ]; then
        echo "ERROR:INTERNAL_ERROR"
        return 1
    else
        echo "ERROR:UNKNOWN_STATE:$vm_status"
        return 1
    fi
}

RESULT=$(check_vm_status)
CHECK_EXIT=$?

STATUS=$(echo "$RESULT" | cut -d: -f1)
ERROR_TYPE=$(echo "$RESULT" | cut -d: -f2)

# Citește starea anterioară
LAST_STATE=""
[ -f "$STATE_FILE" ] && LAST_STATE=$(cat "$STATE_FILE")

echo "$(date '+%Y-%m-%d %H:%M:%S'): VM $VM_ID status: $STATUS ($ERROR_TYPE)" >> "$LOG_FILE"

# Verifică dacă starea s-a schimbat
CURRENT_STATE="$STATUS:$ERROR_TYPE"

if [ "$LAST_STATE" != "$CURRENT_STATE" ]; then
    # Starea s-a schimbat - trimite email
    SEND_EMAIL=true
    
    if [ $CHECK_EXIT -eq 0 ]; then
        # VM acum e OK
        if [[ "$LAST_STATE" == STOPPED:* ]] || [[ "$LAST_STATE" == ERROR:* ]]; then
            # Era oprit/eroare, acum e pornit - trimite email de recovery
            SUBJECT="✅ VM $VM_ID RECOVERED - Running on $HOSTNAME"
            BODY="VM $VM_ID has RECOVERED and is now RUNNING\n"
            BODY+="Previous state: $LAST_STATE\n"
            BODY+="Current state: RUNNING\n"
            BODY+="Recovery time: $DATE\n"
            BODY+="Host: $HOSTNAME\n\n"
            BODY+="VM is now operating normally."
        else
            # Altă tranziție către RUNNING - nu trimite email
            SEND_EMAIL=false
        fi
    else
        # VM are probleme
        SUBJECT="⚠️ VM $VM_ID $STATUS on $HOSTNAME"
        BODY="VM $VM_ID Status: $STATUS\n"
        BODY+="Error Type: $ERROR_TYPE\n"
        BODY+="Check Time: $DATE\n"
        BODY+="Host: $HOSTNAME\n\n"
        
        if [ "$STATUS" = "STOPPED" ]; then
            BODY+="VM is stopped. To start: qm start $VM_ID"
        elif [ "$ERROR_TYPE" = "INTERNAL_ERROR" ]; then
            BODY+="VM has internal-error (KVM crash)."
        elif [ "$ERROR_TYPE" = "PROCESS_MISSING" ]; then
            BODY+="VM marked as running but process missing."
        fi
    fi
    
    # Trimite email dacă e necesar
    if [ "$SEND_EMAIL" = true ]; then
        echo -e "$BODY" | mail -s "$SUBJECT" root
        echo "$(date '+%Y-%m-%d %H:%M:%S'): Email sent - state changed from '$LAST_STATE' to '$CURRENT_STATE'" >> "$LOG_FILE"
    else
        echo "$(date '+%Y-%m-%d %H:%M:%S'): State changed but no email needed" >> "$LOG_FILE"
    fi
else
    echo "$(date '+%Y-%m-%d %H:%M:%S'): No email - state unchanged ($CURRENT_STATE)" >> "$LOG_FILE"
fi

# Salvează starea curentă
echo "$CURRENT_STATE" > "$STATE_FILE"

exit $CHECK_EXIT