/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/
let hasDifferentOriginAncestorFlag = false;
let sameOriginWindowChainCache = null;
function getParentWindowIfSameOrigin(w) {
    if (!w.parent || w.parent === w) {
        return null;
    }
    // Cannot really tell if we have access to the parent window unless we try to access something in it
    try {
        const location = w.location;
        const parentLocation = w.parent.location;
        if (location.origin !== 'null' && parentLocation.origin !== 'null' && location.origin !== parentLocation.origin) {
            hasDifferentOriginAncestorFlag = true;
            return null;
        }
    }
    catch (e) {
        hasDifferentOriginAncestorFlag = true;
        return null;
    }
    return w.parent;
}
export class IframeUtils {
    /**
     * Returns a chain of embedded windows with the same origin (which can be accessed programmatically).
     * Having a chain of length 1 might mean that the current execution environment is running outside of an iframe or inside an iframe embedded in a window with a different origin.
     * To distinguish if at one point the current execution environment is running inside a window with a different origin, see hasDifferentOriginAncestor()
     */
    static getSameOriginWindowChain() {
        if (!sameOriginWindowChainCache) {
            sameOriginWindowChainCache = [];
            let w = window;
            let parent;
            do {
                parent = getParentWindowIfSameOrigin(w);
                if (parent) {
                    sameOriginWindowChainCache.push({
                        window: w,
                        iframeElement: w.frameElement || null
                    });
                }
                else {
                    sameOriginWindowChainCache.push({
                        window: w,
                        iframeElement: null
                    });
                }
                w = parent;
            } while (w);
        }
        return sameOriginWindowChainCache.slice(0);
    }
    /**
     * Returns the position of `childWindow` relative to `ancestorWindow`
     */
    static getPositionOfChildWindowRelativeToAncestorWindow(childWindow, ancestorWindow) {
        if (!ancestorWindow || childWindow === ancestorWindow) {
            return {
                top: 0,
                left: 0
            };
        }
        let top = 0, left = 0;
        const windowChain = this.getSameOriginWindowChain();
        for (const windowChainEl of windowChain) {
            top += windowChainEl.window.scrollY;
            left += windowChainEl.window.scrollX;
            if (windowChainEl.window === ancestorWindow) {
                break;
            }
            if (!windowChainEl.iframeElement) {
                break;
            }
            const boundingRect = windowChainEl.iframeElement.getBoundingClientRect();
            top += boundingRect.top;
            left += boundingRect.left;
        }
        return {
            top: top,
            left: left
        };
    }
}