# -*- coding: utf-8 -*-

# Copyright (c) 2009 - 2019 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing the history menu.
"""


import sys

from PyQt5.QtCore import (
    pyqtSignal, Qt, QMimeData, QUrl, QModelIndex, QSortFilterProxyModel,
    QAbstractProxyModel
)
from PyQt5.QtWidgets import QMenu

from E5Gui.E5ModelMenu import E5ModelMenu
from E5Gui import E5MessageBox

from .HistoryModel import HistoryModel

import UI.PixmapCache


class HistoryMenuModel(QAbstractProxyModel):
    """
    Class implementing a model for the history menu.
    
    It maps the first bunch of items of the source model to the root.
    """
    MOVEDROWS = 15
    
    def __init__(self, sourceModel, parent=None):
        """
        Constructor
        
        @param sourceModel reference to the source model (QAbstractItemModel)
        @param parent reference to the parent object (QObject)
        """
        super(HistoryMenuModel, self).__init__(parent)
        
        self.__treeModel = sourceModel
        
        self.setSourceModel(sourceModel)
    
    def bumpedRows(self):
        """
        Public method to determine the number of rows moved to the root.
        
        @return number of rows moved to the root (integer)
        """
        first = self.__treeModel.index(0, 0)
        if not first.isValid():
            return 0
        return min(self.__treeModel.rowCount(first), self.MOVEDROWS)
    
    def columnCount(self, parent=None):
        """
        Public method to get the number of columns.
        
        @param parent index of parent (QModelIndex)
        @return number of columns (integer)
        """
        if parent is None:
            parent = QModelIndex()
        
        return self.__treeModel.columnCount(self.mapToSource(parent))
    
    def rowCount(self, parent=None):
        """
        Public method to determine the number of rows.
        
        @param parent index of parent (QModelIndex)
        @return number of rows (integer)
        """
        if parent is None:
            parent = QModelIndex()
        
        if parent.column() > 0:
            return 0
        
        if not parent.isValid():
            folders = self.sourceModel().rowCount()
            bumpedItems = self.bumpedRows()
            if (
                bumpedItems <= self.MOVEDROWS and
                bumpedItems == self.sourceModel().rowCount(
                    self.sourceModel().index(0, 0))
            ):
                folders -= 1
            return bumpedItems + folders
        
        if parent.internalId() == sys.maxsize:
            if parent.row() < self.bumpedRows():
                return 0
        
        idx = self.mapToSource(parent)
        defaultCount = self.sourceModel().rowCount(idx)
        if idx == self.sourceModel().index(0, 0):
            return defaultCount - self.bumpedRows()
        
        return defaultCount
    
    def mapFromSource(self, sourceIndex):
        """
        Public method to map an index to the proxy model index.
        
        @param sourceIndex reference to a source model index (QModelIndex)
        @return proxy model index (QModelIndex)
        """
        sourceRow = self.__treeModel.mapToSource(sourceIndex).row()
        return self.createIndex(
            sourceIndex.row(), sourceIndex.column(), sourceRow)
    
    def mapToSource(self, proxyIndex):
        """
        Public method to map an index to the source model index.
        
        @param proxyIndex reference to a proxy model index (QModelIndex)
        @return source model index (QModelIndex)
        """
        if not proxyIndex.isValid():
            return QModelIndex()
        
        if proxyIndex.internalId() == sys.maxsize:
            bumpedItems = self.bumpedRows()
            if proxyIndex.row() < bumpedItems:
                return self.__treeModel.index(
                    proxyIndex.row(), proxyIndex.column(),
                    self.__treeModel.index(0, 0))
            if (
                bumpedItems <= self.MOVEDROWS and
                bumpedItems == self.sourceModel().rowCount(
                    self.__treeModel.index(0, 0))
            ):
                bumpedItems -= 1
            return self.__treeModel.index(proxyIndex.row() - bumpedItems,
                                          proxyIndex.column())
        
        historyIndex = self.__treeModel.sourceModel().index(
            proxyIndex.internalId(), proxyIndex.column())
        treeIndex = self.__treeModel.mapFromSource(historyIndex)
        return treeIndex
    
    def index(self, row, column, parent=None):
        """
        Public method to create an index.
        
        @param row row number for the index (integer)
        @param column column number for the index (integer)
        @param parent index of the parent item (QModelIndex)
        @return requested index (QModelIndex)
        """
        if parent is None:
            parent = QModelIndex()
        
        if (
            row < 0 or
            column < 0 or
            column >= self.columnCount(parent) or
            parent.column() > 0
        ):
            return QModelIndex()
        
        if not parent.isValid():
            return self.createIndex(row, column, sys.maxsize)
        
        treeIndexParent = self.mapToSource(parent)
        
        bumpedItems = 0
        if treeIndexParent == self.sourceModel().index(0, 0):
            bumpedItems = self.bumpedRows()
        treeIndex = self.__treeModel.index(
            row + bumpedItems, column, treeIndexParent)
        historyIndex = self.__treeModel.mapToSource(treeIndex)
        historyRow = historyIndex.row()
        if historyRow == -1:
            historyRow = treeIndex.row()
        return self.createIndex(row, column, historyRow)

    def parent(self, index):
        """
        Public method to get the parent index.
        
        @param index index of item to get parent (QModelIndex)
        @return index of parent (QModelIndex)
        """
        offset = index.internalId()
        if offset == sys.maxsize or not index.isValid():
            return QModelIndex()
        
        historyIndex = self.__treeModel.sourceModel().index(
            index.internalId(), 0)
        treeIndex = self.__treeModel.mapFromSource(historyIndex)
        treeIndexParent = treeIndex.parent()
        
        sourceRow = self.sourceModel().mapToSource(treeIndexParent).row()
        bumpedItems = self.bumpedRows()
        if (
            bumpedItems <= self.MOVEDROWS and
            bumpedItems == self.sourceModel().rowCount(
                self.sourceModel().index(0, 0))
        ):
            bumpedItems -= 1
        
        return self.createIndex(bumpedItems + treeIndexParent.row(),
                                treeIndexParent.column(),
                                sourceRow)
    
    def mimeData(self, indexes):
        """
        Public method to return the mime data.
        
        @param indexes list of indexes (QModelIndexList)
        @return mime data (QMimeData)
        """
        urls = []
        for index in indexes:
            url = index.data(HistoryModel.UrlRole)
            urls.append(url)
        
        mdata = QMimeData()
        mdata.setUrls(urls)
        return mdata


class HistoryMostVisitedMenuModel(QSortFilterProxyModel):
    """
    Class implementing a model to show the most visited history entries.
    """
    def __init__(self, sourceModel, parent=None):
        """
        Constructor
        
        @param sourceModel reference to the source model (QAbstractItemModel)
        @param parent reference to the parent object (QObject)
        """
        super(HistoryMostVisitedMenuModel, self).__init__(parent)
        
        self.setDynamicSortFilter(True)
        self.setSourceModel(sourceModel)
    
    def lessThan(self, left, right):
        """
        Public method used to sort the displayed items.
        
        @param left index of left item (QModelIndex)
        @param right index of right item (QModelIndex)
        @return true, if left is less than right (boolean)
        """
        from .HistoryFilterModel import HistoryFilterModel
        frequency_L = self.sourceModel().data(
            left, HistoryFilterModel.FrequencyRole)
        dateTime_L = self.sourceModel().data(
            left, HistoryModel.DateTimeRole)
        frequency_R = self.sourceModel().data(
            right, HistoryFilterModel.FrequencyRole)
        dateTime_R = self.sourceModel().data(
            right, HistoryModel.DateTimeRole)
        
        # Sort results in descending frequency-derived score. If frequencies
        # are equal, sort on most recently viewed
        if frequency_R == frequency_L:
            return dateTime_R < dateTime_L
        
        return frequency_R < frequency_L


class HistoryMenu(E5ModelMenu):
    """
    Class implementing the history menu.
    
    @signal openUrl(QUrl, str) emitted to open a URL in the current tab
    @signal newTab(QUrl, str) emitted to open a URL in a new tab
    @signal newBackgroundTab(QUrl, str) emitted to open a URL in a new
        background tab
    @signal newWindow(QUrl, str) emitted to open a URL in a new window
    @signal newPrivateWindow(QUrl, str) emitted to open a URL in a new
        private window
    """
    openUrl = pyqtSignal(QUrl, str)
    newTab = pyqtSignal(QUrl, str)
    newBackgroundTab = pyqtSignal(QUrl, str)
    newWindow = pyqtSignal(QUrl, str)
    newPrivateWindow = pyqtSignal(QUrl, str)
    
    def __init__(self, parent=None, tabWidget=None):
        """
        Constructor
        
        @param parent reference to the parent widget (QWidget)
        @param tabWidget reference to the tab widget managing the browser
            tabs (HelpTabWidget
        """
        E5ModelMenu.__init__(self, parent)
        
        self.__tabWidget = tabWidget
        self.__mw = parent
        
        self.__historyManager = None
        self.__historyMenuModel = None
        self.__initialActions = []
        self.__mostVisitedMenu = None
        
        self.__closedTabsMenu = QMenu(self.tr("Closed Tabs"))
        self.__closedTabsMenu.aboutToShow.connect(
            self.__aboutToShowClosedTabsMenu)
        self.__tabWidget.closedTabsManager().closedTabAvailable.connect(
            self.__closedTabAvailable)
        
        self.setMaxRows(7)
        
        self.activated.connect(self.__activated)
        self.setStatusBarTextRole(HistoryModel.UrlStringRole)
    
    def __activated(self, idx):
        """
        Private slot handling the activated signal.
        
        @param idx index of the activated item (QModelIndex)
        """
        if self._keyboardModifiers & Qt.ControlModifier:
            self.newTab.emit(
                idx.data(HistoryModel.UrlRole),
                idx.data(HistoryModel.TitleRole))
        elif self._keyboardModifiers & Qt.ShiftModifier:
            self.newWindow.emit(
                idx.data(HistoryModel.UrlRole),
                idx.data(HistoryModel.TitleRole))
        else:
            self.openUrl.emit(
                idx.data(HistoryModel.UrlRole),
                idx.data(HistoryModel.TitleRole))
    
    def prePopulated(self):
        """
        Public method to add any actions before the tree.
       
        @return flag indicating if any actions were added (boolean)
        """
        if self.__historyManager is None:
            from WebBrowser.WebBrowserWindow import WebBrowserWindow
            self.__historyManager = WebBrowserWindow.historyManager()
            self.__historyMenuModel = HistoryMenuModel(
                self.__historyManager.historyTreeModel(), self)
            self.setModel(self.__historyMenuModel)
        
        # initial actions
        for act in self.__initialActions:
            self.addAction(act)
        if len(self.__initialActions) != 0:
            self.addSeparator()
        self.setFirstSeparator(self.__historyMenuModel.bumpedRows())
        
        return False
    
    def postPopulated(self):
        """
        Public method to add any actions after the tree.
        """
        if len(self.__historyManager.history()) > 0:
            self.addSeparator()
        
        if self.__mostVisitedMenu is None:
            self.__mostVisitedMenu = HistoryMostVisitedMenu(10, self)
            self.__mostVisitedMenu.setTitle(self.tr("Most Visited"))
            self.__mostVisitedMenu.openUrl.connect(self.openUrl)
            self.__mostVisitedMenu.newTab.connect(self.newTab)
            self.__mostVisitedMenu.newBackgroundTab.connect(
                self.newBackgroundTab)
            self.__mostVisitedMenu.newWindow.connect(self.newWindow)
            self.__mostVisitedMenu.newPrivateWindow.connect(
                self.newPrivateWindow)
        self.addMenu(self.__mostVisitedMenu)
        act = self.addMenu(self.__closedTabsMenu)
        act.setIcon(UI.PixmapCache.getIcon("trash.png"))
        act.setEnabled(self.__tabWidget.canRestoreClosedTab())
        self.addSeparator()
        
        act = self.addAction(UI.PixmapCache.getIcon("history.png"),
                             self.tr("Show All History..."))
        act.triggered.connect(self.showHistoryDialog)
        act = self.addAction(UI.PixmapCache.getIcon("historyClear.png"),
                             self.tr("Clear History..."))
        act.triggered.connect(self.__clearHistoryDialog)
    
    def setInitialActions(self, actions):
        """
        Public method to set the list of actions that should appear first in
        the menu.
        
        @param actions list of initial actions (list of QAction)
        """
        self.__initialActions = actions[:]
        for act in self.__initialActions:
            self.addAction(act)
    
    def showHistoryDialog(self):
        """
        Public slot to show the history dialog.
        """
        from .HistoryDialog import HistoryDialog
        dlg = HistoryDialog(self.__mw)
        dlg.openUrl.connect(self.openUrl)
        dlg.newTab.connect(self.newTab)
        dlg.newBackgroundTab.connect(self.newBackgroundTab)
        dlg.newWindow.connect(self.newWindow)
        dlg.newPrivateWindow.connect(self.newPrivateWindow)
        dlg.show()
    
    def __clearHistoryDialog(self):
        """
        Private slot to clear the history.
        """
        if self.__historyManager is not None and E5MessageBox.yesNo(
                self,
                self.tr("Clear History"),
                self.tr("""Do you want to clear the history?""")):
            self.__historyManager.clear()
            self.__tabWidget.clearClosedTabsList()
    
    def __aboutToShowClosedTabsMenu(self):
        """
        Private slot to populate the closed tabs menu.
        """
        fm = self.__closedTabsMenu.fontMetrics()
        maxWidth = fm.width('m') * 40
        
        import WebBrowser.WebBrowserWindow
        self.__closedTabsMenu.clear()
        index = 0
        for tab in self.__tabWidget.closedTabsManager().allClosedTabs():
            title = fm.elidedText(tab.title, Qt.ElideRight, maxWidth)
            act = self.__closedTabsMenu.addAction(
                WebBrowser.WebBrowserWindow.WebBrowserWindow.icon(tab.url),
                title)
            act.setData(index)
            act.triggered.connect(
                lambda: self.__tabWidget.restoreClosedTab(act))
            index += 1
        self.__closedTabsMenu.addSeparator()
        self.__closedTabsMenu.addAction(
            self.tr("Restore All Closed Tabs"),
            self.__tabWidget.restoreAllClosedTabs)
        self.__closedTabsMenu.addAction(
            self.tr("Clear List"),
            self.__tabWidget.clearClosedTabsList)
    
    def __closedTabAvailable(self, avail):
        """
        Private slot to handle changes of the availability of closed tabs.
        
        @param avail flag indicating the availability of closed tabs (boolean)
        """
        self.__closedTabsMenu.setEnabled(avail)


class HistoryMostVisitedMenu(E5ModelMenu):
    """
    Class implementing the most visited history menu.
    
    @signal openUrl(QUrl, str) emitted to open a URL in the current tab
    @signal newTab(QUrl, str) emitted to open a URL in a new tab
    @signal newBackgroundTab(QUrl, str) emitted to open a URL in a new
        background tab
    @signal newWindow(QUrl, str) emitted to open a URL in a new window
    @signal newPrivateWindow(QUrl, str) emitted to open a URL in a new
        private window
    """
    openUrl = pyqtSignal(QUrl, str)
    newTab = pyqtSignal(QUrl, str)
    newBackgroundTab = pyqtSignal(QUrl, str)
    newWindow = pyqtSignal(QUrl, str)
    newPrivateWindow = pyqtSignal(QUrl, str)
    
    def __init__(self, count, parent=None):
        """
        Constructor
        
        @param count maximum number of entries to be shown (integer)
        @param parent reference to the parent widget (QWidget)
        """
        E5ModelMenu.__init__(self, parent)
        
        self.__historyMenuModel = None
        
        self.setMaxRows(count + 1)
        
##        self.activated.connect(self.__activated)
        self.setStatusBarTextRole(HistoryModel.UrlStringRole)
    
    def __activated(self, idx):
        """
        Private slot handling the activated signal.
        
        @param idx index of the activated item (QModelIndex)
        """
        if self._keyboardModifiers & Qt.ControlModifier:
            self.newTab.emit(
                idx.data(HistoryModel.UrlRole),
                idx.data(HistoryModel.TitleRole))
        elif self._keyboardModifiers & Qt.ShiftModifier:
            self.newWindow.emit(
                idx.data(HistoryModel.UrlRole),
                idx.data(HistoryModel.TitleRole))
        else:
            self.openUrl.emit(
                idx.data(HistoryModel.UrlRole),
                idx.data(HistoryModel.TitleRole))
    
    def prePopulated(self):
        """
        Public method to add any actions before the tree.
       
        @return flag indicating if any actions were added (boolean)
        """
        if self.__historyMenuModel is None:
            from WebBrowser.WebBrowserWindow import WebBrowserWindow
            historyManager = WebBrowserWindow.historyManager()
            self.__historyMenuModel = HistoryMostVisitedMenuModel(
                historyManager.historyFilterModel(), self)
            self.setModel(self.__historyMenuModel)
        self.__historyMenuModel.sort(0)
        
        return False
