'use strict';
(function() {

	var secBefore = 2000;
	var secAfter = 5000;
	var secBetweenDupAssets = 10e3;
	var minVidSize = 500e3;
	var maxVidSize = 25e6;
	var maxContentRange = 25e6;
	var videoExtensions = [
		'af', '3gp', 'asf', 'avchd', 'avi', 'cam', 'dsh', 'flv', 'm1v', 'm2v',
		'fla', 'flr', 'sol', 'm4v', 'mkv', 'wrap', 'mng', 'mov', 'mpeg', 'mpg',
		'mpe', 'mp4', 'mxf', 'nsv', 'ogg', 'rm', 'svi', 'smi', 'wmv', 'webm'
	];
	var extensionsReg = new RegExp('\\.' + videoExtensions.join('$|\\.') + '$');
	var videoContentTypesPrefixes = ['binary/octet-stream', 'video/', 'flv-application/', 'media'];

	var bannedContentTypes = ['video/mp2t','video/f4m','video/f4f'];
	var bannedFiletypes = ['ts'];
	var bannedFiletypesReg = new RegExp('\\.' + bannedFiletypes.join('$|\\.') + '$');
	var whitelistReqTypes = ['object', 'xmlhttprequest', 'other'];

	var topVideoAssetDomains = [
		'2mdn.net',
		'innovid.com',
		'serving-sys.com',
		'btrll.com',
		'teads.tv',
		'tubemogul.com'
	];

	if ( !String.prototype.endsWith ) {
		String.prototype.endsWith = function(searchString, position) {
			var subjectString = this.toString();
			if ( typeof position !== 'number' || !isFinite(position) ||
				Math.floor(position) !== position || position > subjectString.length) {
				position = subjectString.length;
			}
			position -= searchString.length;
			var lastIndex = subjectString.indexOf(searchString, position);
			return lastIndex !== -1 && lastIndex === position;
		};
	}

	function isPixelRequest(request) {
		return (request.type === 'image' || request.responseStatus === 204) &&
				request.size <= 1000;
	}

	function isVpaidOrVastRequest(request) {
		var lowerCaseUrl = request.url.toLowerCase();
		return lowerCaseUrl.indexOf('vpaid') !== -1 || lowerCaseUrl.indexOf('vast') !== -1;
	}

	function hasValidRequestType(request) {
		return whitelistReqTypes.indexOf(request.type) >= 0;
	}

	function stripQueryParams(url) {
		return url.split('?',1)[0];
	}

	function parseHostnameFromUrl(url) {
		var parser = document.createElement('a');
		parser.href = url;
		return parser.hostname;
	}

	function hasDomain(url, domain) {
		return parseHostnameFromUrl(url).endsWith(domain);
	}

	function findHeader(headers, key) {
		var header;
		for ( var i = 0; i < headers.length; i += 1 ) {
			header = headers[i];
			if ( header.name.toLowerCase() === key ) {
				return header;
			}
		}
		return null;
	}

	function validVideoType(vtype) {
		var goodType = videoContentTypesPrefixes.some(function(prefix) {
			return vtype.indexOf(prefix) === 0;
		});
		return goodType;
	}

	function assetMsgKey(assetReq) {
		var url = stripQueryParams(assetReq.url);
		var key = assetReq.frameId + '-' + url;
		return key;
	}

	var PageNetworkTrafficCollector = function(tabId) {
		this.tabId = tabId;
		this.displayAdFound = false;
		this.requests = {};
		this.msgsBeingSent = {};
		this.assetsSeen = {};
		this.allRedirects = {};
	};

	var globalPageContainer = {
		collectors: {},
		dyingCollectors: {},

		cleanupCollector: function(tabId) {
			if ( tabId in this.collectors ) {
				delete globalPageContainer.collectors[tabId];
			}
		},

		onNewNavigation: function(details) {
			var tabId = details.tabId;
			this.cleanupCollector(tabId);

			this.collectors[tabId] = new PageNetworkTrafficCollector(tabId);
		},

		onNavigationCommitted: function(details) {

		},

		onNavigationCompleted: function(details) {

		},

		onTabClose: function(tabId, closeInfo) {

			this.cleanupCollector(tabId);
			delete this.collectors[tabId];
		},

		onDisplayAdFound: function(tabId) {
			this.collectors[tabId].displayAdFound = true;
		},

		getRandId: function() {
			return String(Math.floor(Math.random() * 1e9));
		},

		getCollector: function(tabId) {
			if ( this.collectors.hasOwnProperty(tabId) ) {
				return this.collectors[tabId];
			}
			return null;
		},

		forwardCall: function(details, collectorMemberFunction) {
			var collector = this.getCollector(details.tabId);
			if ( collector !== null ) {
				collectorMemberFunction.apply(collector, [details]);
			}
		}
	};

	PageNetworkTrafficCollector.prototype.sendLogMessageToTabConsole = function() {
		var logMessage = Array.from(arguments).join(' ');
		var message = {message: logMessage, event: 'console-log-message'};
		browser.tabs.sendMessage(this.tabId, message);
	};

	PageNetworkTrafficCollector.prototype.sendToTab = function(assetReq, reqs, curPageUrl, isValidAd) {
		var msg = {};
		msg.assets = [];
		msg.event_data = {};
		if ( isValidAd ) {
			msg.event = 'new-video-ad';
			msg.requests = reqs;
			msg.requests.sort(function(reqA, reqB) {return reqA.requestTimestamp - reqB.requestTimestamp;});
			if ( assetReq ) {
				msg.assets = [assetReq];
			}
		} else {
			msg.requests = reqs.map(function(request) {
				return parseHostnameFromUrl(request.url);
			});
			msg.assets = [{
				url: parseHostnameFromUrl(assetReq.url),
				contentType: assetReq.contentType,
				size: assetReq.size
			}];
			msg.event = 'new-invalid-video-ad';
		}
		msg.origUrl = curPageUrl;
		msg.displayAdFound = this.displayAdFound;

		browser.tabs.sendMessage(this.tabId, msg);
	};

	PageNetworkTrafficCollector.prototype.getRedirKey = function(url, frameId) {
		return url + ':' + frameId;
	};

	PageNetworkTrafficCollector.prototype.seenBefore = function(request) {
		var oldTime = this.assetsSeen[assetMsgKey(request)];
		if ( oldTime && (request.requestTimestamp-oldTime < secBetweenDupAssets)){

			return true;
		}
		return false;
	};

	PageNetworkTrafficCollector.prototype.recordSeenAsset = function(request) {
		this.assetsSeen[assetMsgKey(request)] = request.requestTimestamp;
	};

	PageNetworkTrafficCollector.prototype.onBeforeRequest = function(details) {
		var req = {
			url: details.url,
			type: details.type,
			httpMethod: details.method,
			frameId: details.frameId,
			parentFrameId: details.parentFrameId,
			requestTimestamp: details.timeStamp,
		};
		this.requests[details.requestId] = req;
	};

	PageNetworkTrafficCollector.prototype.onSendHeaders = function(details) {
		var request, header;
		request = this.requests[details.requestId];
		header = request && findHeader(details.requestHeaders, 'x-requested-with');
		if ( header && header.value.toLowerCase().indexOf('flash') > -1 ) {
			request.from_flash = true;
		}
	};

	PageNetworkTrafficCollector.prototype.onHeadersReceived = function(details) {
		var getFrameDetails = {
			tabId: details.tabId,
			processId: null,
			frameId: details.frameId
		};
		var pageNetworkTrafficController = this;
		browser.webNavigation.getFrame(getFrameDetails).then(function(frameDetails) {
			if ( frameDetails && frameDetails.url ) {
				pageNetworkTrafficController._onHeadersReceived(details, frameDetails);
			}
		});
	};

	PageNetworkTrafficCollector.prototype._onHeadersReceived = function(details, frameDetails) {
		var contentSize, contentRange;

		var request = this.requests[details.requestId];
		if ( request ) {
			var redirParent = this.allRedirects[this.getRedirKey(details.url, details.frameId)];
			var header = request && findHeader(details.responseHeaders, 'content-type');
			var contentType = header && header.value.toLowerCase();

			if ( contentType){
				request.contentType = contentType;
			}
			header = request && findHeader(details.responseHeaders, 'content-length');
			contentSize = header && header.value;
			if ( contentSize ) {
				request.size = request.size || 0;
				request.size += parseInt(contentSize);
			}
			header = request && findHeader(details.responseHeaders, 'content-range');
			contentRange = header && header.value;
			if ( contentRange ) {
				request.contentRange = parseInt(contentRange.split('/')[1]);
			}

			var frameUrl = null;
			if ( frameDetails && frameDetails.url ) {
				frameUrl = frameDetails.url;
			}
			if ( !this.bannedRequest(request) &&
				(this.isVideoReq(frameUrl, request) || (redirParent && redirParent.isVideo))) {
				request.isVideo = true;
			}
		}
	};

	PageNetworkTrafficCollector.prototype.onBeforeRedirect = function(details) {
		var request = this.requests[details.requestId];
		if ( request ) {
			if ( request.redirects ) {
				request.redirects.push(details.redirectUrl);
			} else {
				request.redirects = [details.redirectUrl];
			}
			this.allRedirects[this.getRedirKey(details.redirectUrl, details.frameId)] = request;
		}
	};

	PageNetworkTrafficCollector.prototype.isYoutubeMastheadRequest = function(url) {
		var re = /video_masthead/;
		return this.hasYoutubeDomain(url) && re.test(url);
	};
	PageNetworkTrafficCollector.prototype.isYoutubeVideoRequest = function(srcUrl, destUrl) {
		if ( !this.hasYoutubeDomain(srcUrl) ) {
			return false;
		}

		var re = /https?:\/\/r.*?\.googlevideo\.com\/videoplayback\?/;
		return re.test(destUrl);
	};
	PageNetworkTrafficCollector.prototype.processResponse = function(requestDetails, frameDetails) {
		var request;
		if ( requestDetails ) {
			request = this.requests[requestDetails.requestId];
			if ( request ) {
				request.responseStatus = requestDetails.statusCode;
				request.responseTimestamp = requestDetails.timeStamp;

				var frameUrl = null;
				if ( frameDetails && frameDetails.url ) {
					frameUrl = frameDetails.url;
				}

				var requestUrl = null;
				if ( request.url ) {
					requestUrl = request.url;
				}

				if ( this.isYoutubeAdReq(frameUrl, requestUrl) ) {
					var videoId = this.parseYoutubeVideoIdFromUrl(requestUrl);
					if ( videoId ) {
						request.isYoutubeAd = true;
						request.isVideo = true;
						request.url = 'https://www.youtube.com/watch?v=' + this.parseYoutubeVideoIdFromUrl(requestUrl);
					}
				} else if ( !this.bannedRequest(request) &&
						(this.isVideo || this.isVideoReq(frameUrl, request))) {
					request.isVideo = true;
				}

				if ( request.isVideo ) {

					var msgKey = assetMsgKey(request);
					this.msgsBeingSent[msgKey] = request;
					if ( !this.seenBefore(request) ) {
						this.sendMsgWhenQuiet(msgKey);
					}
					this.recordSeenAsset(request);
				}
			}
		}
	};

	PageNetworkTrafficCollector.prototype.onResponseStarted = function(responseDetails) {
		if ( responseDetails.frameId < 0 ) {
			responseDetails.frameId = 99999;

		}
		var getFrameDetails = {
			tabId: responseDetails.tabId,
			processId: null,
			frameId: responseDetails.frameId
		};
		var pageNetworkTrafficController = this;
		browser.webNavigation.getFrame(getFrameDetails).then(function(frameDetails) {
			if ( frameDetails && frameDetails.url ) {
				pageNetworkTrafficController.processResponse(responseDetails, frameDetails);
			}
		});
	};

	PageNetworkTrafficCollector.prototype.hasBannedFiletype = function(request) {
		var url = stripQueryParams(request.url);
		if ( bannedFiletypesReg.exec(url) ) {
			return true;
		} else {
			return false;
		}
	};

	PageNetworkTrafficCollector.prototype.checkContentHeaders = function(request) {
		if ( request.contentType && validVideoType(request.contentType) ) {
			return true;
		}
		return false;
	};

	PageNetworkTrafficCollector.prototype.checkUrlExtension = function(request) {
		var url = stripQueryParams(request.url);
		if ( extensionsReg.exec(url) ) {
			return true;
		} else {
			return false;
		}
	};

	PageNetworkTrafficCollector.prototype.isVideoReq = function(srcUrl, request) {
		if ( this.isYoutubeVideoRequest(srcUrl, request.url) ) {
			return false;
		}
		return this.checkUrlExtension(request) || this.checkContentHeaders(request);
	};
	PageNetworkTrafficCollector.prototype.hasYoutubeDomain = function(url) {
		var hostname = parseHostnameFromUrl(url) ;
		if ( hostname === 'www.youtube.com' ) {
			return true;
		}
		return false;
	};
	PageNetworkTrafficCollector.prototype.parseYoutubeVideoIdFromUrl = function(url) {
		var re = /^https?:\/\/www\.youtube\.com\/get_video_info.*(?:\?|&)video_id=(.*?)(?:$|&)/;
		var match = re.exec(url);
		if ( match && match.length > 1 ) {
			return match[1];
		}

		re = /^https?:\/\/www\.youtube\.com\/embed\/(.*?)(?:$|\?)/;
		match = re.exec(url);
		if ( match && match.length > 1 ) {
			return match[1];
		}

		re = /^https?:\/\/www\.youtube\.com\/watch\?v=(.*$)/;
		match = re.exec(url);
		if ( match && match.length > 1 ) {
			return match[1];
		}
		return null;
	};

	PageNetworkTrafficCollector.prototype.isYoutubeGetVideoInfoReq = function(url) {
		var re = /^https?:\/\/www\.youtube\.com\/get_video_info\?/;
		return re.test(url);
	};
	PageNetworkTrafficCollector.prototype.isYoutubeAdReq = function(srcUrl, destUrl) {

		if ( !this.hasYoutubeDomain(srcUrl) ||
			!this.isYoutubeGetVideoInfoReq(destUrl)) {
			return false;
		}
		if ( this.parseYoutubeVideoIdFromUrl(srcUrl) ===
			this.parseYoutubeVideoIdFromUrl(destUrl) &&
			!this.isYoutubeMastheadRequest(destUrl)) {
			return false;
		}
		return true;
	};

	PageNetworkTrafficCollector.prototype.bannedRequest = function(request) {
		return this.bannedVideoType(request) || this.hasBannedFiletype(request) || this.bannedVideoSize(request);
	};

	PageNetworkTrafficCollector.prototype.bannedVideoType = function(request) {
		var badType = false;
		if ( request.contentType ) {
			badType = bannedContentTypes.some(function(prefix) {
				return request.contentType.indexOf(prefix) >= 0;
			});
		}
		return badType;
	};

	PageNetworkTrafficCollector.prototype.bannedVideoSize = function(request) {
		if ( request.size !== null ) {
			if ( request.size < minVidSize || request.size > maxVidSize || request.contentRange > maxContentRange ) {
				return true;
			}
		}
		return false;
	};

	PageNetworkTrafficCollector.prototype.grabTagReqs = function(tabRequests, assetRequest) {
		var minTimestamp, maxTimestamp;
		minTimestamp = assetRequest.requestTimestamp - secBefore;
		maxTimestamp = assetRequest.requestTimestamp + secAfter;

		var filteredRequests = tabRequests.filter(function(request) {
			return (request.requestTimestamp > minTimestamp &&
				request.requestTimestamp < maxTimestamp &&
				request.frameId === assetRequest.frameId &&
				request.url !== assetRequest.url &&
				(hasValidRequestType(request) ||
				isPixelRequest(request)));
		});

		return filteredRequests;
	};

	PageNetworkTrafficCollector.prototype.isValidVideoAd = function(assetRequest, tagRequests) {
		var hasVpaidOrVastRequest = tagRequests.some(function(tagRequest) {
			return isVpaidOrVastRequest(tagRequest);
		});
		if ( hasVpaidOrVastRequest ) {
			return true;
		}
		var hasTopVideoAssetDomain = topVideoAssetDomains.some(function(assetDomain) {
			return hasDomain(assetRequest.url, assetDomain);
		});

		return hasTopVideoAssetDomain;
	};

	PageNetworkTrafficCollector.prototype.sendMsgWhenQuiet = function(msgKey) {
		var _this = this,
			origPageUrl, msgAssetReq;
		msgAssetReq = this.msgsBeingSent[msgKey];
		browser.tabs.get(this.tabId, function(tab) {origPageUrl = tab.url;});

		setTimeout(function() {
			var rawRequests = [];
			if ( globalPageContainer.collectors[_this.tabId] === _this ) {
				for ( var reqId in _this.requests ) {
					rawRequests.push(_this.requests[reqId]);
				}
				var tagReqs = _this.grabTagReqs(rawRequests, msgAssetReq);

				if ( _this.isValidVideoAd(msgAssetReq, tagReqs) ) {
					_this.sendToTab(msgAssetReq, tagReqs, origPageUrl, true);
				} else {

					_this.sendToTab(msgAssetReq, tagReqs, origPageUrl, false);
				}

			} else {

			}
			delete _this.msgsBeingSent[msgKey];
		}, secAfter+secBefore);
	};

	PageNetworkTrafficCollector.prototype.existingMessage = function(candidateRequest) {
		var frameMsg = this.msgsBeingSent[candidateRequest.frameId];
		if ( frameMsg ) {
			return frameMsg;
		} else {
			return null;
		}
	};

	browser.webRequest.onBeforeRequest.addListener(function(details) {
		globalPageContainer.forwardCall(details, PageNetworkTrafficCollector.prototype.onBeforeRequest);
	}, {urls: ['http://*/*', 'https://*/*']}, []);

	browser.webRequest.onSendHeaders.addListener(function(details) {
		globalPageContainer.forwardCall(details, PageNetworkTrafficCollector.prototype.onSendHeaders);
	}, {urls: ['http://*/*', 'https://*/*']}, ['requestHeaders']);

	browser.webRequest.onHeadersReceived.addListener(function(details) {
		globalPageContainer.forwardCall(details, PageNetworkTrafficCollector.prototype.onHeadersReceived);
	}, {urls: ['http://*/*', 'https://*/*']}, ['responseHeaders']);

	browser.webRequest.onBeforeRedirect.addListener(function(details) {
		globalPageContainer.forwardCall(details, PageNetworkTrafficCollector.prototype.onBeforeRedirect);
	}, {urls: ['http://*/*', 'https://*/*']}, []);

	browser.webRequest.onResponseStarted.addListener(function(details) {
		globalPageContainer.forwardCall(details, PageNetworkTrafficCollector.prototype.onResponseStarted);
	}, {urls: ['http://*/*', 'https://*/*']}, ['responseHeaders']);

	browser.webNavigation.onBeforeNavigate.addListener(function(details) {
		if ( details.frameId === 0 ) {
			globalPageContainer.onNewNavigation(details);
		}
	}, {});

	browser.webNavigation.onCommitted.addListener(function(details) {
		if ( details.frameId === 0 ) {
			globalPageContainer.onNavigationCommitted(details);
		}
	});

	browser.webNavigation.onCompleted.addListener(function(details) {
		if ( details.frameId === 0 ) {
			globalPageContainer.onNavigationCompleted(details);
		}
	});

	browser.tabs.onRemoved.addListener(function(tabId, closeInfo) {
		globalPageContainer.onTabClose(tabId, closeInfo);
	});

	browser.runtime.onMessage.addListener(function(message, sender, sendResponse) {
		if ( message.event === 'new-ad' && message.data.event === 'ad' ) {
			var tabId = sender.tab.id;
			if ( tabId ) {
				globalPageContainer.onDisplayAdFound(tabId);
			}
		}
	});
})();