window.windowManager = (function () {

    const container = document.getElementById("AppWindows");
    let zIndexCounter = 1000;

    function open(options) {
        const win = document.createElement("div");
        win.className = "app-window";
        win.style.width = (options.width || 800) + "px";
        win.style.height = (options.height || 600) + "px";
        win.style.left = "50px";
        win.style.top = "50px";
        win.style.zIndex = ++zIndexCounter;

        // Titelbalk
        const titlebar = document.createElement("div");
        titlebar.className = "app-titlebar";

        const title = document.createElement("div");
        title.className = "title";
        title.textContent = options.title;

        const buttons = document.createElement("div");
        buttons.className = "buttons";

        const btnMin = document.createElement("button");
        btnMin.textContent = "_";

        const btnClose = document.createElement("button");
        btnClose.textContent = "x";

        buttons.appendChild(btnMin);
        buttons.appendChild(btnClose);

        titlebar.appendChild(title);
        titlebar.appendChild(buttons);

        // Content
        const content = document.createElement("div");
        content.className = "app-content";

        const iframe = document.createElement("iframe");
        iframe.src = options.url;

        content.appendChild(iframe);

        win.appendChild(titlebar);
        win.appendChild(content);
        container.appendChild(win);

        // Drag
        makeDraggable(win, titlebar);

        // Close
        btnClose.addEventListener("click", () => {
            win.remove();
        });

        // Minimize
        btnMin.addEventListener("click", () => {
            win.style.display = "none";
            minimizeToAppsBar(options, win);
        });

        return win;
    }

    function minimizeToAppsBar(app, win) {
        const bar = document.getElementById("AppsBar");

        const icon = document.createElement("div");
        icon.className = "app-icon";
        icon.title = app.title;

        const img = document.createElement("img");
        img.src = app.icon;
        img.width = 32;
        img.height = 32;

        icon.appendChild(img);

        icon.addEventListener("click", () => {
            win.style.display = "flex";
            win.style.zIndex = ++zIndexCounter;
            icon.remove();
        });

        bar.appendChild(icon);
    }

    function makeDraggable(win, handle) {
        let offsetX = 0, offsetY = 0;
        let dragging = false;

        handle.addEventListener("mousedown", (e) => {
            dragging = true;
            offsetX = e.clientX - win.offsetLeft;
            offsetY = e.clientY - win.offsetTop;
            win.style.zIndex = ++zIndexCounter;
        });

        document.addEventListener("mousemove", (e) => {
            if (!dragging) return;
            win.style.left = (e.clientX - offsetX) + "px";
            win.style.top = (e.clientY - offsetY) + "px";
        });

        document.addEventListener("mouseup", () => {
            dragging = false;
        });
    }

    return { open };

})();