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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
const {
screenshotContentSpec,
const STRINGS_URI = "devtools/shared/locales/screenshot.properties";
const L10N = new LocalizationHelper(STRINGS_URI);
loader.lazyRequireGetter(
this,
["getCurrentZoom", "getRect"],
true
);
exports.ScreenshotContentActor = class ScreenshotContentActor extends Actor {
constructor(conn, targetActor) {
super(conn, screenshotContentSpec);
this.targetActor = targetActor;
}
_getRectForNode(node) {
const originWindow = this.targetActor.ignoreSubFrames
? node.ownerGlobal
: node.ownerGlobal.top;
return getRect(originWindow, node, node.ownerGlobal);
}
/**
* Retrieve some window-related information that will be passed to the parent process
* to actually generate the screenshot.
*
* @param {Object} args
* @param {Boolean} args.fullpage: Should the screenshot be the height of the whole page
* @param {String} args.selector: A CSS selector for the element we should take the
* screenshot of. The function will return true for the `error` property
* if the screenshot does not match any element.
* @param {String} args.nodeActorID: The actorID of the node actor matching the element
* we should take the screenshot of.
* @returns {Object} An object with the following properties:
* - error {Boolean}: Set to true if an issue was encountered that prevents
* taking the screenshot
* - messages {Array<Object{text, level}>}: An array of objects representing
* the messages emitted throught the process and their level.
* - windowDpr {Number}: Value of window.devicePixelRatio
* - windowZoom {Number}: The page current zoom level
* - rect {Object}: Object with left, top, width and height properties
* representing the rect **inside the browser element** that should be rendered.
* For screenshot of the current viewport, we return null, as expected by the
* `drawSnapshot` API.
*/
prepareCapture({ fullpage, selector, nodeActorID }) {
const { window } = this.targetActor;
// Use the override if set, note that the override is not returned by
//
// on whether there's an override, this is a bit suspect.
const windowDpr =
window.browsingContext.top.overrideDPPX || window.devicePixelRatio;
const windowZoom = getCurrentZoom(window);
const messages = [];
// If we're going to take the current view of the page, we don't need to compute a rect,
// since it's the default behaviour of drawSnapshot.
if (!fullpage && !selector && !nodeActorID) {
return {
rect: null,
messages,
windowDpr,
windowZoom,
};
}
let left;
let top;
let width;
let height;
if (fullpage) {
// We don't want to render the scrollbars
const winUtils = window.windowUtils;
const scrollbarHeight = {};
const scrollbarWidth = {};
winUtils.getScrollbarSize(false, scrollbarWidth, scrollbarHeight);
left = 0;
top = 0;
width =
window.innerWidth +
window.scrollMaxX -
window.scrollMinX -
scrollbarWidth.value;
height =
window.innerHeight +
window.scrollMaxY -
window.scrollMinY -
scrollbarHeight.value;
} else if (selector) {
const node = window.document.querySelector(selector);
if (!node) {
messages.push({
level: "warn",
text: L10N.getFormatStr("screenshotNoSelectorMatchWarning", selector),
});
return {
error: true,
messages,
};
}
({ left, top, width, height } = this._getRectForNode(node));
} else if (nodeActorID) {
const nodeActor = this.conn.getActor(nodeActorID);
if (!nodeActor) {
messages.push({
level: "error",
text: `Screenshot actor failed to find Node actor for '${nodeActorID}'`,
});
return {
error: true,
messages,
};
}
({ left, top, width, height } = this._getRectForNode(nodeActor.rawNode));
}
return {
windowDpr,
windowZoom,
rect: { left, top, width, height },
messages,
};
}
};