favoritter/web/static/js/app.js

// Favoritter — minimal JavaScript for HTMX configuration and form helpers.
// SPDX-License-Identifier: AGPL-3.0-or-later

(function () {
    "use strict";

    // Auto-include the CSRF token in all HTMX requests.
    document.body.addEventListener("htmx:configRequest", function (event) {
        var csrfCookie = getCookie("csrf_token");
        if (csrfCookie) {
            event.detail.headers["X-CSRF-Token"] = csrfCookie;
        }

        // For the tag search input, send the current value of the last
        // comma-separated segment as the 'q' parameter.
        var elt = event.detail.elt;
        if (elt && elt.id === "tags") {
            var val = elt.value;
            var parts = val.split(",");
            var lastPart = parts[parts.length - 1].trim();
            event.detail.parameters["q"] = lastPart;
        }
    });

    // Update aria-expanded and announce suggestion count after HTMX swaps.
    document.body.addEventListener("htmx:afterSwap", function (event) {
        var target = event.detail.target;
        if (!target) return;

        // Focus management: if swapped content has autofocus, focus it.
        var autoFocus = target.querySelector("[autofocus]");
        if (autoFocus) {
            autoFocus.focus();
        }

        // Tag suggestions: update combobox state.
        if (target.id === "tag-suggestions") {
            var input = document.getElementById("tags");
            var items = target.querySelectorAll("[role='option']");
            var count = items.length;

            if (input) {
                input.setAttribute("aria-expanded", count > 0 ? "true" : "false");
            }

            // Announce suggestion count to screen readers.
            var status = document.getElementById("tag-status");
            if (status) {
                status.textContent = count > 0
                    ? count + " forslag tilgjengelig"
                    : "Ingen forslag";
            }

            // Reset active descendant tracking.
            activeIndex = -1;
            clearActiveDescendant();
        }
    });

    // After a successful HTMX DELETE, redirect if the element has a data-redirect.
    document.body.addEventListener("htmx:afterRequest", function (event) {
        if (event.detail.successful && event.detail.verb === "delete") {
            var redirect = event.detail.elt.getAttribute("data-redirect");
            if (redirect) {
                window.location.href = redirect;
            }
        }
    });

    // --- Tag autocomplete combobox pattern ---
    var activeIndex = -1;

    // Handle keyboard navigation in the tag suggestions listbox.
    document.addEventListener("keydown", function (event) {
        var input = document.getElementById("tags");
        if (!input || document.activeElement !== input) return;

        var listbox = document.getElementById("tag-suggestions");
        if (!listbox) return;
        var items = listbox.querySelectorAll("[role='option']");
        if (items.length === 0) return;

        switch (event.key) {
        case "ArrowDown":
            event.preventDefault();
            activeIndex = Math.min(activeIndex + 1, items.length - 1);
            setActiveDescendant(items);
            break;
        case "ArrowUp":
            event.preventDefault();
            // Allow arrowing back to -1 to deselect all options.
            activeIndex = Math.max(activeIndex - 1, -1);
            if (activeIndex === -1) {
                clearActiveDescendant();
                clearAriaSelected(items);
            } else {
                setActiveDescendant(items);
            }
            break;
        case "Enter":
            if (activeIndex >= 0 && activeIndex < items.length) {
                event.preventDefault();
                addTag(null, items[activeIndex].textContent.trim());
            }
            break;
        case "Escape":
            closeSuggestions();
            break;
        }
    });

    function setActiveDescendant(items) {
        for (var i = 0; i < items.length; i++) {
            items[i].setAttribute("aria-selected", i === activeIndex ? "true" : "false");
        }
        var input = document.getElementById("tags");
        if (input && activeIndex >= 0) {
            var activeItem = items[activeIndex];
            if (!activeItem.id) {
                activeItem.id = "tag-option-" + activeIndex;
            }
            input.setAttribute("aria-activedescendant", activeItem.id);
            activeItem.scrollIntoView({ block: "nearest" });
        }
    }

    function clearActiveDescendant() {
        var input = document.getElementById("tags");
        if (input) {
            input.removeAttribute("aria-activedescendant");
        }
    }

    function clearAriaSelected(items) {
        for (var i = 0; i < items.length; i++) {
            items[i].setAttribute("aria-selected", "false");
        }
    }

    function closeSuggestions() {
        var listbox = document.getElementById("tag-suggestions");
        if (listbox) {
            while (listbox.firstChild) {
                listbox.removeChild(listbox.firstChild);
            }
        }
        var input = document.getElementById("tags");
        if (input) {
            input.setAttribute("aria-expanded", "false");
        }
        activeIndex = -1;
    }

    // Add a selected tag to the tag input.
    window.addTag = function (element, tagName) {
        var input = document.getElementById("tags");
        if (!input) return;

        var parts = input.value.split(",").map(function (s) { return s.trim(); });
        parts[parts.length - 1] = tagName;
        input.value = parts.join(", ") + ", ";
        input.focus();

        closeSuggestions();
    };

    function getCookie(name) {
        var match = document.cookie.match(new RegExp("(^| )" + name + "=([^;]+)"));
        return match ? match[2] : null;
    }
})();