// canvas-actions.js — creating a canvas from a normal page.
//
// The canvas view itself owns everything else (rename, delete, editing); this
// only covers the one action that has to start from the page, since a folder
// with no canvases has no canvas view to reach.
//
// Reuses openModal and postReplace from page/actions.js, which the page
// template loads first.

// validCanvasName mirrors canvasNameRe in canvas.go. Checking here only buys a
// better error message — the server rejects the same set regardless.
function validCanvasName(name) {
    if (!name || name.length > 100) return false;
    if (name.charAt(0) === '.') return false;
    return !/[\/\\]/.test(name);
}

function newCanvas() {
    var input = document.createElement('input');
    input.type = 'text';
    input.className = 'input';
    input.placeholder = 'Canvas name';

    openModal({
        title: 'New canvas',
        body: input,
        confirm: {
            label: 'CREATE',
            onConfirm: function () {
                var name = input.value.trim();
                if (!validCanvasName(name)) {
                    alert('A canvas name cannot be empty, start with a dot, or contain a slash.');
                    return;
                }
                closeModal();
                var base = window.location.pathname;
                if (base.slice(-1) !== '/') base += '/';
                var target = base + '?canvas=' + encodeURIComponent(name);
                postReplace(target + '&create=1', null, target);
            }
        }
    });
}