from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *
from PyQt5.QtWebEngineWidgets import *
import sys


class WebView(QWebEngineView):
	def __init__(self, parent):
		super().__init__(parent)
	def createWindow(self, webWindowType):
		return main_demo.browser


class MainDemo(QMainWindow):
	def __init__(self, *args, **kwargs):
		super().__init__(*args, **kwargs)
		self.setWindowTitle('ZYH浏览器')
		self.setWindowIcon(QIcon('icons/penguin.png'))
		self.resize(800, 500)
		self.show()
		# 添加URL地址栏
		self.urlbar = QLineEdit()
		# 让地址栏支持输入地址回车访问
		self.urlbar.returnPressed.connect(self.navigate_to_url)
		# 添加标签栏
		self.tabs = QTabWidget()
		self.tabs.setDocumentMode(True)
		self.tabs.tabBarDoubleClicked.connect(self.tab_open)
		self.tabs.currentChanged.connect(self.current_tab_changed)
		# 允许关闭标签
		self.tabs.setTabsClosable(True)
		# 设置关闭按钮的槽
		self.tabs.tabCloseRequested.connect(self.close_current_tab)
		self.add_new_tab(QUrl('http://zyhnb.vcn.ink'), '主页')
		self.setCentralWidget(self.tabs)
		new_tab_action = QAction(QIcon('icons/add_page.png'), 'New Page', self)
		new_tab_action.triggered.connect(self.add_new_tab)
		# 添加导航栏
		navigation_bar = QToolBar('Navigation')
		# 设定图标大小
		navigation_bar.setIconSize(QSize(16, 16))
		self.addToolBar(navigation_bar)
		# 添加前进、后退、停止加载和刷新的按钮
		back_button = QAction(QIcon('icons/back.png'), 'Back', self)
		forward_button = QAction(QIcon('icons/forward.png'), 'Forward', self)
		stop_button = QAction(QIcon('icons/stop.png'), 'Stop', self)
		reload_button = QAction(QIcon('icons/renew.png'), 'Reload', self)
		back_button.triggered.connect(self.tabs.currentWidget().back)
		forward_button.triggered.connect(self.tabs.currentWidget().forward)
		stop_button.triggered.connect(self.tabs.currentWidget().stop)
		reload_button.triggered.connect(self.tabs.currentWidget().reload)
		# 将按钮添加到导航栏上
		navigation_bar.addAction(back_button)
		navigation_bar.addAction(forward_button)
		navigation_bar.addAction(stop_button)
		navigation_bar.addAction(reload_button)
		navigation_bar.addSeparator()
		navigation_bar.addWidget(self.urlbar)

	
	# 响应回车按钮，将浏览器当前访问的URL设置为用户输入的URL
	def navigate_to_url(self):
		current_url = QUrl(self.urlbar.text())
		if current_url.scheme() == '':
			current_url.setScheme('http')
		self.tabs.currentWidget().load(current_url)


	# 将当前网页的链接更新到地址栏
	def renew_urlbar(self, url, browser=None):
		# 非当前窗口不更新URL
		if browser != self.tabs.currentWidget():
			return
		self.urlbar.setText(url.toString())
		self.urlbar.setCursorPosition(0)


	# 添加新的标签页
	def add_new_tab(self, qurl=QUrl(''), label='Blank'):
		# 设置浏览器
		self.browser = WebView(self)
		self.browser.load(qurl)
		# 为标签添加索引方便管理
		i = self.tabs.addTab(self.browser, label)
		self.tabs.setCurrentIndex(i)
		self.browser.urlChanged.connect(lambda qurl, browser=self.browser: self.renew_urlbar(qurl, self.browser))
		# 将标签标题改为网页相关的标题
		self.browser.loadFinished.connect(lambda _, i=i, browser=self.browser: self.tabs.setTabText(i, self.browser.page().title()))
	
	
	# 双击标签栏打开新页面
	def tab_open(self, i):
		if i == -1:
			self.add_new_tab()
	def current_tab_changed(self, i):
		qurl = self.tabs.currentWidget().url()
		self.renew_urlbar(qurl, self.tabs.currentWidget())
	def close_current_tab(self, i):
		# 若当前标签页只有一个则不关闭
		if self.tabs.count() < 2:
			return
		self.tabs.removeTab(i)



if __name__ == '__main__':
	my_application = QApplication(sys.argv) #创建QApplication类的实例
	main_demo = MainDemo()
	main_demo.show()
	my_application.exec_()