JS File System Access API

fs-access.js

<button id="pick-folder">Select Open Library Folder</button>
    <ul id="file-list"></ul>

<script type="text/javascript">
async function getStoredDirectory() {
            if ("storage" in navigator && "getDirectory" in navigator.storage) {
                try {
                    const dirHandle = await navigator.storage.getDirectory();
                    return dirHandle.getFileHandle("selected-folder").catch(() => null);
                } catch (err) {
                    console.warn("Could not retrieve stored folder:", err);
                }
            }
            return null;
        }

        async function saveDirectoryHandle(dirHandle) {
            try {
                const dir = await navigator.storage.getDirectory();
                await dirHandle.requestPermission({ mode: "read" });
                await dir.addEntry("selected-folder", dirHandle);
            } catch (err) {
                console.warn("Could not save folder handle:", err);
            }
        }

        async function listFiles(dirHandle) {
            const fileList = document.getElementById("file-list");
            fileList.innerHTML = "";

            for await (const entry of dirHandle.values()) {
                const li = document.createElement("li");
                li.textContent = entry.name;
                fileList.appendChild(li);
            }
        }

        async function loadFilesOnStartup() {
            const storedHandle = await getStoredDirectory();
            if (storedHandle) {
                console.log("Using stored directory handle...");
                listFiles(storedHandle);
            }
        }

        document.getElementById("pick-folder").addEventListener("click", async () => {
            try {
                const dirHandle = await window.showDirectoryPicker();
                await saveDirectoryHandle(dirHandle);
                listFiles(dirHandle);
            } catch (err) {
                console.error("Error accessing folder:", err);
            }
        });

        // Try to auto-load files if permission is granted
        loadFilesOnStartup();
</script>