import { DBTable } from "./DBTable";

String.prototype["hashCode"] = function () {
    let hash = 0;
    if (this.length == 0) return hash;
    for (let i = 0; i < this.length; i++) {
        let char = this.charCodeAt(i);
        hash = (hash << 5) - hash + char;
        hash = hash & hash; // Convert to 32bit integer
    }
    return hash;
};

let rowSignature;

if (Object["values"]) {
    console.log("using Object.values");
    rowSignature = (row, hash) => {
        return Object["values"](row).join(".");
    };
} else {
    rowSignature = (row, hash = false) => {
        let result: any = JSON.stringify(row);
        if (hash) result = result.hashCode();

        return result;
    };
}

/**
 *
 * @param {any[]} array
 * @param {boolean} hash
 * @return {Array}
 */
export function uniqueRows(array: any[], hash: boolean = false) {
    let n = {},
        r = [];
    for (let i = 0; i < array.length; i++) {
        // Use a hash based on the actual data                      in the object, not the object's memory address or instance id
        // This ensures that the objects are truly unique
        let strRep = rowSignature(array[i], hash);
        if (!n[strRep]) {
            n[strRep] = true;
            r.push(array[i]);
        }
    }
    return r;
}

export function Uint8ToString(u8a): string {
    // from... https://stackoverflow.com/questions/12710001/how-to-convert-uint8-array-to-base64-encoded-string
    let CHUNK_SZ = 0x8000;
    let c = [];
    for (let i = 0; i < u8a.length; i += CHUNK_SZ) {
        c.push(String.fromCharCode.apply(null, u8a.subarray(i, i + CHUNK_SZ)));
    }
    return c.join("");
}

export function StringToUint8(string: string) {
    // from... https://jsperf.com/string-to-uint8array

    let uint = new Uint8Array(string.length);
    for (let i = 0, j = string.length; i < j; ++i) {
        uint[i] = string.charCodeAt(i);
    }

    return uint;
}

export function getTagsFromRow(row: any): DBTable<{ tag: string }> {
    if (row.tags && typeof row.tags === "string") {
        return new DBTable(row.tags.split(",").map(a => ({ tag: a })));
    } else if (row.getAnnotations) {
        return row?.getAnnotations();
    } else {
        console.warn("Looks like we are trying get tags on an object that ising supported!");
        return new DBTable();
    }
}