(() => {
const svgElement = document.querySelector('#device-svg');
if (!svgElement) {
    return;
}

const DEVICE_TYPE_ID = Number(svgElement.dataset.deviceTypeId || 0);
const API_LOAD_PORTS = '/api/device_type_ports.php?action=load';
const API_SAVE_PORTS = '/api/device_type_ports.php?action=save';
const DEFAULT_PORT_TYPE_ID = null;

let ports = [];
let selectedPortId = null;
let isDragging = false;
let dragOffset = { x: 0, y: 0 };

bindSvgEvents();
loadPorts();

function bindSvgEvents() {
    svgElement.addEventListener('click', onSvgClick);
    svgElement.addEventListener('mousemove', onSvgMouseMove);
    svgElement.addEventListener('mouseup', onSvgMouseUp);

    const saveButton = document.querySelector('[data-save-svg-ports]');
    if (saveButton) {
        saveButton.addEventListener('click', (event) => {
            event.preventDefault();
            savePorts();
        });
    }
}

function onSvgClick(event) {
    if (event.target.classList.contains('port-point')) {
        selectPort(event.target.dataset.id);
        return;
    }

    // New ports are only created while SHIFT is held.
    if (!event.shiftKey) {
        return;
    }

    const point = getSvgCoordinates(event);
    createPort(point.x, point.y);
}

function createPort(x, y) {
    const id = generateTempId();
    const port = {
        id,
        name: `Port ${ports.length + 1}`,
        port_type_id: DEFAULT_PORT_TYPE_ID,
        x,
        y,
        metadata: null
    };

    ports.push(port);
    renderPort(port);
    selectPort(id);
}

function renderPort(port) {
    const circle = document.createElementNS('http://www.w3.org/2000/svg', 'circle');
    circle.setAttribute('cx', port.x);
    circle.setAttribute('cy', port.y);
    circle.setAttribute('r', 6);
    circle.classList.add('port-point');
    circle.dataset.id = port.id;

    circle.addEventListener('mousedown', (e) => {
        startDrag(e, port.id);
        e.stopPropagation();
    });

    svgElement.appendChild(circle);
}

function rerenderPorts() {
    svgElement.querySelectorAll('.port-point').forEach((node) => node.remove());
    ports.forEach(renderPort);
    if (selectedPortId !== null) {
        selectPort(selectedPortId);
    }
}

function selectPort(id) {
    selectedPortId = id;

    document.querySelectorAll('.port-point').forEach((el) => {
        el.classList.toggle('selected', el.dataset.id === String(id));
    });

    const selected = getPortById(id);
    fillSidebar(selected);
}

function fillSidebar(port) {
    const nameField = document.querySelector('[data-port-name]');
    const typeField = document.querySelector('[data-port-type-id]');
    const xField = document.querySelector('[data-port-x]');
    const yField = document.querySelector('[data-port-y]');

    if (nameField) nameField.value = port?.name || '';
    if (typeField) typeField.value = port?.port_type_id || '';
    if (xField) xField.value = port ? Math.round(port.x) : '';
    if (yField) yField.value = port ? Math.round(port.y) : '';
}

function resetSidebar() {
    fillSidebar(null);
}

function startDrag(event, portId) {
    const port = getPortById(portId);
    if (!port) return;

    isDragging = true;
    selectedPortId = portId;

    const point = getSvgCoordinates(event);
    dragOffset.x = port.x - point.x;
    dragOffset.y = port.y - point.y;
}

function onSvgMouseMove(event) {
    if (!isDragging || !selectedPortId) return;

    const port = getPortById(selectedPortId);
    if (!port) return;

    const point = getSvgCoordinates(event);
    port.x = point.x + dragOffset.x;
    port.y = point.y + dragOffset.y;

    rerenderPorts();
}

function onSvgMouseUp() {
    isDragging = false;
}

function deleteSelectedPort() {
    if (!selectedPortId) {
        return;
    }

    if (!confirm('Ausgewaehlten Port loeschen?')) {
        return;
    }

    ports = ports.filter((port) => String(port.id) !== String(selectedPortId));
    selectedPortId = null;
    rerenderPorts();
    resetSidebar();
}

function loadPorts() {
    if (!DEVICE_TYPE_ID) {
        console.warn('SVG Editor: DEVICE_TYPE_ID fehlt auf #device-svg');
        return;
    }

    fetch(`${API_LOAD_PORTS}&device_type_id=${DEVICE_TYPE_ID}`)
        .then((res) => res.json())
        .then((data) => {
            if (!Array.isArray(data)) {
                throw new Error('Antwortformat ungueltig');
            }

            ports = data
                .filter((entry) => entry && typeof entry === 'object')
                .map((entry) => ({
                    id: entry.id,
                    name: String(entry.name || ''),
                    port_type_id: entry.port_type_id ? Number(entry.port_type_id) : null,
                    x: Number(entry.x || 0),
                    y: Number(entry.y || 0),
                    metadata: entry.metadata || null
                }));

            rerenderPorts();
        })
        .catch((err) => {
            console.error('Fehler beim Laden der Ports', err);
        });
}

function savePorts() {
    if (!DEVICE_TYPE_ID) {
        return;
    }

    fetch(API_SAVE_PORTS, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
            device_type_id: DEVICE_TYPE_ID,
            ports
        })
    })
        .then((res) => res.json())
        .then((data) => {
            if (data?.error) {
                throw new Error(data.error);
            }
            alert('Ports gespeichert');
        })
        .catch((err) => {
            alert('Speichern fehlgeschlagen: ' + err.message);
        });
}

function getSvgCoordinates(event) {
    const pt = svgElement.createSVGPoint();
    pt.x = event.clientX;
    pt.y = event.clientY;
    const transformed = pt.matrixTransform(svgElement.getScreenCTM().inverse());
    return { x: transformed.x, y: transformed.y };
}

function getPortById(id) {
    return ports.find((port) => String(port.id) === String(id));
}

function generateTempId() {
    return 'tmp_' + Math.random().toString(36).slice(2, 11);
}

document.addEventListener('keydown', (event) => {
    if (event.key === 'Delete') {
        deleteSelectedPort();
    }
});
})();