import { gettext } from "django";
import { html, TemplateResult } from "lit-html";
import "./elements/EmptyState";

export function getCookie(name: string): string {
    let cookieValue = "";
    if (document.cookie && document.cookie !== "") {
        const cookies = document.cookie.split(";");
        for (let i = 0; i < cookies.length; i++) {
            const cookie = cookies[i].trim();
            // Does this cookie string begin with the name we want?
            if (cookie.substring(0, name.length + 1) === name + "=") {
                cookieValue = decodeURIComponent(cookie.substring(name.length + 1));
                break;
            }
        }
    }
    return cookieValue;
}

export function convertToSlug(text: string): string {
    return text
        .toLowerCase()
        .replace(/ /g, "-")
        .replace(/[^\w-]+/g, "");
}

export function convertToTitle(text: string): string {
    return text.replace(
        /\w\S*/g,
        function (txt) {
            return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();
        }
    );
}

export function truncate(input?: string, max = 10): string {
    input = input || "";
    const array = input.trim().split(" ");
    const ellipsis = array.length > max ? "..." : "";

    return array.slice(0, max).join(" ") + ellipsis;
}

export function loading<T>(v: T, actual: TemplateResult): TemplateResult {
    if (!v) {
        return html`<ak-empty-state
            ?loading="${true}"
            header=${gettext("Loading")}>
        </ak-empty-state>`;
    }
    return actual;
}

export function camelToSnake(key: string): string {
    const result = key.replace(/([A-Z])/g, " $1");
    return result.split(" ").join("_").toLowerCase();
}

export function groupBy<T>(objects: T[], callback: (obj: T) => string): Array<[string, T[]]> {
    const m = new Map<string, T[]>();
    objects.forEach(obj => {
        const group = callback(obj);
        if (!m.has(group)) {
            m.set(group, []);
        }
        const tProviders = m.get(group) || [];
        tProviders.push(obj);
    });
    return Array.from(m);
}

export function first<T>(...args: Array<T | undefined | null>): T {
    for (let index = 0; index < args.length; index++) {
        const element = args[index];
        if (element !== undefined && element !== null) {
            return element;
        }
    }
    throw new Error(`No compatible arg given: ${args}`);
}