// WINDOW MANAGER
const desktop = document.getElementById('desktop');
const bglayer = document.getElementById('background-layer');
const newWindowBtn = document.getElementById('new-window-btn');
let zIndexCounter = 1;

let focusedWindow = null;
let windows = {};
let windowHooks = [];

function uniqueid() {
    // always start with a letter (for DOM friendlyness)
    var idstr = String.fromCharCode(Math.floor((Math.random() * 25) + 65));
    do {
        // between numbers and characters (48 is 0 and 90 is Z (42-48 = 90)
        var ascicode = Math.floor((Math.random() * 42) + 48);
        if (ascicode < 58 || ascicode > 64) {
            // exclude all chars between : (58) and @ (64)
            idstr += String.fromCharCode(ascicode);
        }
    } while (idstr.length < 32);

    return (idstr);
}

function fadeOut(fadeTarget, speed, callback) {
    let eee = 0;
    var fadeEffect = setInterval(function () {
        if (!fadeTarget.style.opacity) {
            fadeTarget.style.opacity = 1;
        }
        fadeTarget.style.transform = `rotate3d(1, 0, 0, ${eee}deg)`;
        if (fadeTarget.style.opacity > 0) {
            fadeTarget.style.opacity -= 0.1;
            eee += 10;
        } else {
            clearInterval(fadeEffect);
            callback();
        }
    }, speed);
}

function killWind(id) {
    const windowDiv = windows[id]?.windElems?.windowDiv;
    if (typeof (windowDiv) == "undefined") {
        console.warn("Attempted to close undefined window..");
        return;
    };
    fadeOut(windowDiv, 20, function () {
        windowDiv.remove();
        delete windows[id];
        windowHooks.forEach(element => {
            element({ event: "windowDestroy", id: id })
        });
    });
}

function focusWindow(id) {
    const windData = windows[id];
    const windowDiv = windData?.windElems?.windowDiv;
    if (typeof (windData) == "undefined") {
        console.warn("Attempted to focus undefined window..");
        return;
    };
    windowDiv.style.zIndex = zIndexCounter++;
    if (windData.layer == "background") windowDiv.style.zIndex = windowDiv.style.zIndex * -1;
    windowHooks.forEach(element => {
        element({ event: "windowFocused", id: id })
    });
    Object.keys(windows).forEach(key => {
        const element = windows[key];
        if (element.alwaysOnTop) {
            element.windElems.windowDiv.style.zIndex = zIndexCounter + 5;
        }
    });
    focusedWindow = id;
}

function createWindow(url, settings) {
    const windID = uniqueid();
    const name = settings.name;
    const headerless = settings.headerless || false;
    const resizable = settings.resizable !== undefined ? settings.resizable : true;
    const shouldIndent = settings.indent !== undefined ? settings.indent : true;
    const layer = settings.layer || "foreground";

    const windowDiv = document.createElement('div');
    windowDiv.classList.add('window');
    if (headerless) windowDiv.classList.add('window-noborder');
    if (shouldIndent) windowDiv.style.top = '50px';
    if (shouldIndent) windowDiv.style.left = '50px';
    windowDiv.style.zIndex = zIndexCounter++;
    windowDiv.id = windID;

    // Header
    const header = document.createElement('div');
    header.classList.add('window-header');

    if (headerless) header.classList.add("window-hidden");

    const title = document.createElement('div');
    title.classList.add('window-title');
    title.textContent = name || url;

    const closeBtn = document.createElement('button');
    closeBtn.classList.add('window-close-btn');
    closeBtn.textContent = '×';

    header.appendChild(title);
    header.appendChild(closeBtn);
    windowDiv.appendChild(header);

    // iframe
    const iframe = document.createElement('iframe');
    iframe.classList.add('window-iframe');
    iframe.src = url;
    windowDiv.appendChild(iframe);
    iframe.onload = function () {
        try {
            iframe.contentDocument.oncontextmenu = function () {
                return false;
            };
        } catch { };
    };

    // Add resize handle if resizable
    let resizeHandle = null;
    if (resizable) {
        resizeHandle = document.createElement('div');
        resizeHandle.style.width = '16px';
        resizeHandle.style.height = '16px';
        resizeHandle.style.position = 'absolute';
        resizeHandle.style.right = '0';
        resizeHandle.style.bottom = '0';
        resizeHandle.style.cursor = 'se-resize';
        // Optional: make it visible if you want
        // resizeHandle.style.background = 'rgba(0,0,0,0.2)';
        windowDiv.appendChild(resizeHandle);
    }

    if (layer == "foreground") desktop.appendChild(windowDiv);
    else bglayer.appendChild(windowDiv);

    // Dragging functionality
    let isDragging = false;
    let offsetX, offsetY;

    header.addEventListener('mousedown', (e) => {
        isDragging = true;
        offsetX = e.clientX - windowDiv.getBoundingClientRect().left;
        offsetY = e.clientY - windowDiv.getBoundingClientRect().top;
        focusWindow(windID);
    });

    // Resizing variables
    let isResizing = false;
    let startWidth, startHeight, startX, startY;

    window.addEventListener('mouseup', () => {
        isDragging = false;
        isResizing = false;
    });

    window.addEventListener('mousemove', (e) => {
        if (isDragging) {
            let newX = e.clientX - offsetX;
            let newY = e.clientY - offsetY;

            transformWindow(windID, null, null, newX, newY);


        } else if (isResizing) {
            const dx = e.clientX - startX;
            const dy = e.clientY - startY;

            const newWidth = startWidth + dx;
            const newHeight = startHeight + dy;

            transformWindow(windID, newWidth, newHeight);
        }
    });

    // Resize handle mousedown
    if (resizeHandle) {
        resizeHandle.addEventListener('mousedown', (e) => {
            e.stopPropagation();
            isResizing = true;
            startWidth = windowDiv.offsetWidth;
            startHeight = windowDiv.offsetHeight;
            startX = e.clientX;
            startY = e.clientY;
            focusWindow(windID);
        });
    }

    // Focus window on click
    windowDiv.addEventListener('mousedown', () => {
        focusWindow(windID);
    });



    // Close window
    closeBtn.addEventListener('click', () => {
        killWind(windID);
    });

    const windObj = {
        iframe: iframe,
        windElems: {
            closeBtn: closeBtn,
            windowDiv: windowDiv,
            header: header,
            title: title,
            resizeHandle: resizeHandle
        },
        windID: windID,
        minSizeX: 250,
        minSizeY: 150,
        alwaysOnTop: false,
        layer: layer,
        hideInTaskbar: layer == "background"
    };

    windows[windID] = windObj;
    windowHooks.forEach(element => {
        element({ event: "windowCreate", id: windID, window: windObj })
    });
    return windObj;
}


function transformWindow(id, sizex, sizey, posx, posy, ignoreRects) {
    const windData = windows[id];
    const windowDiv = windData?.windElems?.windowDiv;
    if (typeof (windData) == "undefined") {
        console.warn("Attempted to transform undefined window..");
        return;
    };
    if (sizex) windowDiv.style.width = Math.max(windData.minSizeX, sizex) + 'px';
    if (sizey) windowDiv.style.height = Math.max(windData.minSizeY, sizey) + 'px';
    const desktopRect = desktop.getBoundingClientRect();
    const winRect = windowDiv.getBoundingClientRect();
    if (posx) {
        const newX = ignoreRects ? posx : Math.max(desktopRect.left, Math.min(posx, desktopRect.right - winRect.width));
        windowDiv.style.left = newX - desktopRect.left + 'px';
    }
    if (posy) {
        const newY = ignoreRects ? posy : Math.max(desktopRect.top, Math.min(posy, desktopRect.bottom - winRect.height));
        windowDiv.style.top = newY - desktopRect.top + 'px';
    }

}

function getTransform(id) {
    const windData = windows[id];
    const windowDiv = windData?.windElems?.windowDiv;
    if (typeof windData === "undefined" || !windowDiv) {
        console.warn("Attempted to transform undefined window..");
        return;
    }

    const desktopRect = desktop.getBoundingClientRect();

    // Extract numeric values from style or fallback to computed styles
    const style = windowDiv.style;

    // Helper to parse px values safely
    function parsePx(val) {
        if (!val) return 0;
        return Math.floor(parseFloat(val));
    }

    // Use inline style if present, otherwise computed style
    let topStr = style.top || window.getComputedStyle(windowDiv).top;
    let leftStr = style.left || window.getComputedStyle(windowDiv).left;
    let widthStr = style.width || window.getComputedStyle(windowDiv).width;
    let heightStr = style.height || window.getComputedStyle(windowDiv).height;

    // Parse numbers from strings like "50px"
    const posy = parsePx(topStr);
    const posx = parsePx(leftStr);
    const sizex = parsePx(widthStr);
    const sizey = parsePx(heightStr);

    return {
        x: posx,
        y: posy,
        sizex: sizex,
        sizey: sizey
    };
}


function updateWindowMin(id) {
    const windData = windows[id];
    if (typeof (windData) == "undefined") {
        console.warn("Attempted to update undefined window..");
        return;
    };
    const transform = getTransform(id);
    transformWindow(id,transform.sizex,transform.sizey,transform.posx,transform.posy);

}