/* Requires sqlite3.js, sqlite3.wasm and sql-worker.js(my worker wrapper)
    // MAYBE add service-worker caching with http.vfs splitting
    // MAYBE use opfs vfs with sync support (multiple tabs)
    // example page:
    <script src="sqlite3.js"></script>
    <script src="sqlite-query.js"></script>

    <article class="panel is-primary">
      <div class="panel-block">
        <input class="input" type="text" placeholder="Search" id="mySearch">
        <button id="mySearchBtn" class="button">&#128269;</button>
      </div>
    </article>
    <dialog id="myModal" class="modal">
      <div class="modal-content">
        <button id="modalClose" class="modal-close is-large" aria-label="close">&times;</button>
        <div id="modalDiv"></div>
      </div>
    </dialog>
    */
document.addEventListener('DOMContentLoaded',() => {
    document.getElementById("modalClose").onclick = function() {
        //document.getElementById("modal").classList.remove("modal-is-open");
        document.getElementById("modal").close();
    }
    document.getElementById("search").addEventListener("keyup", function(event){
        if (event.keyCode == 13) { // on enter
            if (typeof globalThis.w === 'undefined') { // load sqlite worker
                console.log("creating worker");
                const workerArgs = [];
                workerArgs.push("sql-worker.js");
                const w = new Worker(...workerArgs);
                w.onmessage = (msg) => { // write results as table rows and links
                    let html = '<table class="table">';
                    msg.data.forEach((row) => { html = html + "<tr><td><a href='" +row[0]+"'>"+row[1]+"</a></td></tr>"});
                    html = html + "</table>";
                    document.getElementById("modalDiv").innerHTML = html;
                    //document.getElementById("modal").classList.add("modal-is-open");
                    document.getElementById("modal").showModal();
                };
                globalThis.w = w; // query worker
                let query = document.getElementById("search").value;
                globalThis.w.postMessage(query);
            } else {
                let query = document.getElementById("search").value;
                globalThis.w.postMessage(query);
            }
        }
    });
});

onmessage = (e) => {
    const opt = {"returnValue": "resultRows"};
    const sql ="SELECT REPLACE(name, '.org', '.html') AS name, snippet(site_pages, 1, '<b>','</b>', '', 64) AS snippet FROM site_pages WHERE data MATCH '"+ e.data +"' ORDER BY rank;";
    if (typeof globalThis.sqlite3InitModule === 'undefined') { // load sqlite3
        importScripts('sqlite3.js'); // mjs module?
        globalThis.sqlite3InitModule().then((sqlite3)=> {
            sqlite3.installOpfsSAHPoolVfs().then((poolUtil)=> { // use opfs for storage
                if (poolUtil.getFileCount() == 0) {
                    console.log("fetching sqlite opfs files");
                    fetch('sqlar.sqlite').then(response => response.arrayBuffer()).then(arrayBuffer => {
                        poolUtil.importDb('/sqlar.sqlite', arrayBuffer); // requires absolute path (lack of transparent naming obscures real name)
                        const db = new poolUtil.OpfsSAHPoolDb('/sqlar.sqlite');
                        globalThis.db = db;
                        const res = db.exec([sql], opt);
                        postMessage(res);
                    });
                } else {
                    console.log("checking existing sqlite opfs files" + poolUtil.getFileNames());
                    fetch('sqlar.sqlite', {method: "HEAD"}).then(response => {
                        console.log("Response headers are: " + response.headers.get("Content-Length"));
                        const db = new poolUtil.OpfsSAHPoolDb('/sqlar.sqlite'); // load existing db to check size against headers
                        console.log("loaded db");
                        const header_size = response.headers.get("Content-Length");
                        const size_sql = "SELECT page_count * page_size as size FROM pragma_page_count(), pragma_page_size();";
                        const size = db.selectArray(size_sql); // selectArray to not include results in db.exec
                        console.log("Header size is: " + header_size + " DB size is: " + size);
                        if (size == header_size) {
                            console.log("Database is up to date");
                            globalThis.db = db;
                            const res = db.exec([sql], opt);
                            postMessage(res);
                        } else {
                            console.log("Updating database with fetch");
                            db.close(); // close before wiping
                            fetch('sqlar.sqlite').then(response => response.arrayBuffer()).then(arrayBuffer => {
                                poolUtil.wipeFiles().then(_ => {
                                    poolUtil.importDb('/sqlar.sqlite', arrayBuffer);
                                    const db = new poolUtil.OpfsSAHPoolDb('/sqlar.sqlite');
                                    globalThis.db = db;
                                    const res = db.exec([sql], opt);
                                    postMessage(res);
                                });
                            });
                        }
                    }).catch((error) => {
                        console.log("Failed to fetch HEAD. Using Existing DB.");
                        const db = new poolUtil.OpfsSAHPoolDb('/sqlar.sqlite');
                        globalThis.db = db;
                        const res = db.exec([sql], opt);
                        postMessage(res);
                    });
                }
            }).catch((error) => {
                console.log("Failed to use opfs using temp db");
                const capi = sqlite3.capi,
                      oo = sqlite3.oo1,
                      wasm = sqlite3.wasm;
                const db = new oo.DB();
                fetch('sqlar.sqlite').then(response => response.arrayBuffer()).then(arrayBuffer => {
                    const bytes = new Uint8Array(arrayBuffer);
                    const p = sqlite3.wasm.allocFromTypedArray(bytes);
                    const rc = sqlite3.capi.sqlite3_deserialize(db.pointer, 'main', p, bytes.length, bytes.length,sqlite3.capi.SQLITE_DESERIALIZE_FREEONCLOSE);
                    //db.checkRc(rc);

                    globalThis.db = db;
                    const res = globalThis.db.exec([sql], opt);
                    postMessage(res);
                });
            });
        });
    }else {
        const res = globalThis.db.exec([sql], opt);
        postMessage(res);
    }
};