d.js

const separator = '\x1e';
const search = '\u001f';

const DB_NAME = 'bangsDB';
const DB_VERSION = 1;
const STORE_NAME = 'bangStore';
const FILE_KEY = 'bang.az.gz';

function openDatabase() {
    return new Promise((resolve, reject) => {
        const request = indexedDB.open(DB_NAME, DB_VERSION);

        request.onerror = (event) => {
            reject(event.target.error);
        };

        request.onsuccess = (event) => {
            resolve(event.target.result);
        };

        request.onupgradeneeded = (event) => {
            const db = event.target.result;
            if (!db.objectStoreNames.contains(STORE_NAME)) {
                db.createObjectStore(STORE_NAME);
            }
        };
    });
}

function getGzipData(db) {
    return new Promise((resolve, reject) => {
        const transaction = db.transaction(STORE_NAME, 'readonly');
        const store = transaction.objectStore(STORE_NAME);
        const getRequest = store.get(FILE_KEY);

        getRequest.onsuccess = (event) => {
            resolve(event.target.result);
        };

        getRequest.onerror = (event) => {
            reject(event.target.error);
        };
    });
}

function storeGzipData(db, arrayBuffer) {
    return new Promise((resolve, reject) => {
        const transaction = db.transaction(STORE_NAME, 'readwrite');
        const store = transaction.objectStore(STORE_NAME);
        const putRequest = store.put(arrayBuffer, FILE_KEY);

        putRequest.onsuccess = () => {
            resolve();
        };

        putRequest.onerror = (event) => {
            reject(event.target.error);
        };
    });
}

function decompressAndHandle(arrayBuffer) {
    const compressedData = new Uint8Array(arrayBuffer);

    fflate.gunzip(compressedData, (err, decompressedData) => {
        if (err) {
            console.error('Error decompressing:', err);
            return;
        }

        const bangs = new TextDecoder().decode(decompressedData);
        const lines = bangs.split('\n');
        const dictionary = {};

        lines.forEach(line => {
            const parts = line.trim().split(separator);
            if (parts.length === 2) {
                const [key, value] = parts;
                dictionary[key] = value;
            }
        });

        doRedirect(dictionary);
    });
}

function doRedirect(dictionary) {
    const params = new URLSearchParams(window.location.search);
    const queryParam = params.get('q');
    if (queryParam) {
        const tokens = queryParam.split(' ');
        const bangTokenIndex = tokens.findIndex(token => token.startsWith('!'));
        let bangKey = null;
        if (bangTokenIndex > -1) {
            bangKey = tokens[bangTokenIndex];
            tokens.splice(bangTokenIndex, 1);
        }
        const searchQuery = tokens.join(' ');

        if (bangKey && bangKey.startsWith('!')) {
            bangKey = bangKey.slice(1);
        }

        if (bangKey && dictionary.hasOwnProperty(bangKey)) {
            const urlTemplate = dictionary[bangKey];
            window.location.href = urlTemplate.replace(search, encodeURIComponent(searchQuery));
        } else {
            window.location.href = 'https://www.google.com/search?q=' + encodeURIComponent(queryParam);
        }
    }
}

openDatabase()
    .then(db => {
        return getGzipData(db).then(cachedData => {
            if (cachedData) {
                decompressAndHandle(cachedData);
            } else {
                fetch('bang.az.gz')
                    .then(response => response.arrayBuffer())
                    .then(arrayBuffer => {
                        return storeGzipData(db, arrayBuffer).then(() => arrayBuffer);
                    })
                    .then(arrayBuffer => {
                        decompressAndHandle(arrayBuffer);
                    })
                    .catch(err => {
                        console.error('Error while fetching/storing/decompressing:', err);
                    });
            }
        });
    })
    .catch(err => {
        console.error('Error opening or retrieving from IndexedDB:', err);
    });