/**
 * Options specific to creating an anchor ("<a>") element.
 */
interface ICreateElementAnchorOptions {
    href?: string;
    target?: string;
    text?: string;
}

/**
 * Options specific to creating an input ("<input>") element.
 */
interface ICreateElementInputOptions {
    checked?: boolean;
    max?: string;
    maxLength?: number;
    min?: string;
    name?: string;
    pattern?: string;
    placeholder?: string;
    step?: string;
    type?: string;
    value?: string;
}

/**
 * Options specific to creating a label ("<label>") element.
 */
interface ICreateElementLabelOptions {
    for?: string;
}

/**
 * Options for setting up event listeners on the element.
 */
interface ICreateElementListenerOptions {
    changeListener?(this: HTMLElement, ev: Event): any;
    clickListener?(this: HTMLElement, ev: MouseEvent): any;
    inputListener?(this: HTMLElement, ev: Event): any;
    onfocus?(this: HTMLElement, ev: FocusEvent): any;
    onkeydown?(this: HTMLElement, ev: KeyboardEvent): any;
    onkeyup?(this: HTMLElement, ev: KeyboardEvent): any;
}

/**
 * Options for setting up the inline-styling of element.
 * NOTE: Relying on CSS styling should be preferred over forcing the higher specificity via inline styles.
 */
interface ICreateElementStyleOptions {
    backgroundColor?: string;
    border?: string;
    color?: string;
    display?: string;
    float?: string;
    fontSize?: string;
    margin?: string;
    marginLeft?: string;
    marginTop?: string;
    overflow?: string;
    padding?: string;
    position?: string;
    visibility?: string;
    whiteSpace?: string;
    width?: string;
}

/**
 * Options for adding an in-game tooltip to the element.
 */
interface ICreateElementTooltipOptions {
    tooltip?: string;
    tooltipleft?: string;
    tooltipsmall?: string;
    tooltiplow?: string;
}

/**
 * All possible configuration options when creating an element.
 */
interface ICreateElementOptions extends
    ICreateElementStyleOptions,
    ICreateElementListenerOptions,
    ICreateElementInputOptions,
    ICreateElementAnchorOptions,
    ICreateElementLabelOptions,
    ICreateElementTooltipOptions {
    /**
     * CSS Class(es) to initially set.
     */
    class?: string;

    /**
     * A (hopefully) unique identifier for the element.
     */
    id?: string;

    innerHTML?: string;
    innerText?: string;
    tabIndex?: number;
}

function setElementAnchor(el: HTMLAnchorElement, params: ICreateElementAnchorOptions) {
    if (params.text !== undefined) {
        el.text = params.text;
    }
    if (params.href !== undefined) {
        el.href = params.href;
    }
    if (params.target !== undefined) {
        el.target = params.target;
    }
}

function setElementInput(el: HTMLInputElement, params: ICreateElementInputOptions) {
    if (params.name !== undefined) {
        el.name = params.name;
    }
    if (params.value !== undefined) {
        el.value = params.value;
    }
    if (params.type !== undefined) {
        el.type = params.type;
    }
    if (params.checked !== undefined) {
        el.checked = params.checked;
    }
    if (params.pattern !== undefined) {
        el.pattern = params.pattern;
    }
    if (params.maxLength !== undefined) {
        el.maxLength = params.maxLength;
    }
    if (params.placeholder !== undefined) {
        el.placeholder = params.placeholder;
    }
    if (params.max !== undefined) {
        el.max = params.max;
    }
    if (params.min !== undefined) {
        el.min = params.min;
    }
    if (params.step !== undefined) {
        el.step = params.step;
    }
}

function setElementLabel(el: HTMLLabelElement, params: ICreateElementLabelOptions) {
    if (params.for !== undefined) {
        el.htmlFor = params.for;
    }
}

function setElementListeners(el: HTMLElement, params: ICreateElementListenerOptions) {
    // tslint:disable:no-unbound-method
    if (params.clickListener !== undefined) {
        el.addEventListener("click", params.clickListener);
    }
    if (params.inputListener !== undefined) {
        el.addEventListener("input", params.inputListener);
    }
    if (params.changeListener !== undefined) {
        el.addEventListener("change", params.changeListener);
    }
    if (params.onkeyup !== undefined) {
        el.addEventListener("keyup", params.onkeyup);
    }
    if (params.onkeydown !== undefined) {
        el.addEventListener("keydown", params.onkeydown);
    }
    if (params.onfocus !== undefined) {
        el.addEventListener("focus", params.onfocus);
    }
    // tslint:enable:no-unbound-method
}

function setElementStyle(el: HTMLElement, params: ICreateElementStyleOptions) {
    if (params.display !== undefined) {
        el.style.display = params.display;
    }
    if (params.visibility !== undefined) {
        el.style.visibility = params.visibility;
    }
    if (params.margin !== undefined) {
        el.style.margin = params.margin;
    }
    if (params.marginLeft !== undefined) {
        el.style.marginLeft = params.marginLeft;
    }
    if (params.marginTop !== undefined) {
        el.style.marginTop = params.marginTop;
    }
    if (params.padding !== undefined) {
        el.style.padding = params.padding;
    }
    if (params.color !== undefined) {
        el.style.color = params.color;
    }
    if (params.border !== undefined) {
        el.style.border = params.border;
    }
    if (params.float !== undefined) {
        el.style.cssFloat = params.float;
    }
    if (params.fontSize !== undefined) {
        el.style.fontSize = params.fontSize;
    }
    if (params.whiteSpace !== undefined) {
        el.style.whiteSpace = params.whiteSpace;
    }
    if (params.width !== undefined) {
        el.style.width = params.width;
    }
    if (params.backgroundColor !== undefined) {
        el.style.backgroundColor = params.backgroundColor;
    }
    if (params.position !== undefined) {
        el.style.position = params.position;
    }
    if (params.overflow !== undefined) {
        el.style.overflow = params.overflow;
    }
}

function setElementTooltip(el: HTMLElement, params: ICreateElementTooltipOptions) {
    if (params.tooltip !== undefined && params.tooltip !== "")     {
        el.className += " tooltip";
        el.appendChild(createElement("span", {
            class: "tooltiptext",
            innerHTML: params.tooltip,
        }));
    } else if (params.tooltipleft !== undefined) {
        el.className += " tooltip";
        el.appendChild(createElement("span", {
            class: "tooltiptextleft",
            innerHTML: params.tooltipleft,
        }));
    } else if (params.tooltipsmall !== undefined) {
        el.className += " tooltip";
        el.appendChild(createElement("span", {
            class: "tooltiptext smallfont",
            innerHTML: params.tooltipsmall,
        }));
    } else if (params.tooltiplow !== undefined) {
        el.className += "tooltip";
        el.appendChild(createElement("span", {
            class: "tooltiptextlow",
            innerHTML: params.tooltiplow,
        }));
    }
}

/**
 * An all-in-one-call way of creating an element to be added to the DOM at some point.
 * @param tagName The HTML tag/element name
 * @param params Additional parameters to set on the element
 */
export function createElement(tagName: string, params: ICreateElementOptions = {}) {
    const el: HTMLElement = document.createElement(tagName);

    if (params.id !== undefined) {
        el.id = params.id;
    }
    if (params.class !== undefined) {
        el.className = params.class;
    }
    if (params.innerHTML !== undefined) {
        el.innerHTML = params.innerHTML;
    }
    if (params.innerText !== undefined) {
        el.innerText = params.innerText;
    }
    if (params.tabIndex !== undefined) {
        el.tabIndex = params.tabIndex;
    }

    setElementAnchor(el as HTMLAnchorElement, params);
    setElementInput(el as HTMLInputElement, params);
    setElementLabel(el as HTMLLabelElement, params);
    setElementListeners(el, params);
    setElementStyle(el, params);
    setElementTooltip(el, params);

    return el;
}