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

# Copyright (c) 2007 - 2019 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing a dialog to browse the log history.
"""


import os

from PyQt5.QtCore import (
    QTimer, QDate, QProcess, QRegExp, Qt, pyqtSlot, QPoint
)
from PyQt5.QtGui import QCursor
from PyQt5.QtWidgets import (
    QHeaderView, QLineEdit, QWidget, QApplication, QDialogButtonBox,
    QTreeWidgetItem
)

from E5Gui import E5MessageBox

from .Ui_SvnLogBrowserDialog import Ui_SvnLogBrowserDialog

import Preferences
import UI.PixmapCache
from Globals import strToQByteArray


class SvnLogBrowserDialog(QWidget, Ui_SvnLogBrowserDialog):
    """
    Class implementing a dialog to browse the log history.
    """
    def __init__(self, vcs, parent=None):
        """
        Constructor
        
        @param vcs reference to the vcs object
        @param parent parent widget (QWidget)
        """
        super(SvnLogBrowserDialog, self).__init__(parent)
        self.setupUi(self)
        
        self.__position = QPoint()
        
        self.buttonBox.button(QDialogButtonBox.Close).setEnabled(False)
        self.buttonBox.button(QDialogButtonBox.Cancel).setDefault(True)
        
        self.upButton.setIcon(UI.PixmapCache.getIcon("1uparrow.png"))
        self.downButton.setIcon(UI.PixmapCache.getIcon("1downarrow.png"))
        
        self.filesTree.headerItem().setText(self.filesTree.columnCount(), "")
        self.filesTree.header().setSortIndicator(0, Qt.AscendingOrder)
        
        self.vcs = vcs
        
        self.__initData()
        
        self.fromDate.setDisplayFormat("yyyy-MM-dd")
        self.toDate.setDisplayFormat("yyyy-MM-dd")
        self.__resetUI()
        
        self.__messageRole = Qt.UserRole
        self.__changesRole = Qt.UserRole + 1
        
        self.process = QProcess()
        self.process.finished.connect(self.__procFinished)
        self.process.readyReadStandardOutput.connect(self.__readStdout)
        self.process.readyReadStandardError.connect(self.__readStderr)
        
        self.rx_sep1 = QRegExp('\\-+\\s*')
        self.rx_sep2 = QRegExp('=+\\s*')
        self.rx_rev1 = QRegExp(
            r'rev ([0-9]+):  ([^|]*) \| ([^|]*) \| ([0-9]+) .*')
        # "rev" followed by one or more decimals followed by a colon followed
        # anything up to " | " (twice) followed by one or more decimals
        # followed by anything
        self.rx_rev2 = QRegExp(
            r'r([0-9]+) \| ([^|]*) \| ([^|]*) \| ([0-9]+) .*')
        # "r" followed by one or more decimals followed by " | " followed
        # anything up to " | " (twice) followed by one or more decimals
        # followed by anything
        self.rx_flags1 = QRegExp(
            r"""   ([ADM])\s(.*)\s+\(\w+\s+(.*):([0-9]+)\)\s*""")
        # three blanks followed by A or D or M followed by path followed by
        # path copied from followed by copied from revision
        self.rx_flags2 = QRegExp('   ([ADM]) (.*)\\s*')
        # three blanks followed by A or D or M followed by path
        
        self.flags = {
            'A': self.tr('Added'),
            'D': self.tr('Deleted'),
            'M': self.tr('Modified'),
            'R': self.tr('Replaced'),
        }
        self.intercept = False
        
        self.__logTreeNormalFont = self.logTree.font()
        self.__logTreeNormalFont.setBold(False)
        self.__logTreeBoldFont = self.logTree.font()
        self.__logTreeBoldFont.setBold(True)
        
        self.__finishCallbacks = []
    
    def __addFinishCallback(self, callback):
        """
        Private method to add a method to be called once the process finished.
        
        The callback methods are invoke in a FIFO style and are consumed. If
        a callback method needs to be called again, it must be added again.
        
        @param callback callback method
        @type function
        """
        if callback not in self.__finishCallbacks:
            self.__finishCallbacks.append(callback)
    
    def __initData(self):
        """
        Private method to (re-)initialize some data.
        """
        self.__maxDate = QDate()
        self.__minDate = QDate()
        self.__filterLogsEnabled = True
        
        self.buf = []        # buffer for stdout
        self.diff = None
        self.__started = False
        self.__lastRev = 0
    
    def closeEvent(self, e):
        """
        Protected slot implementing a close event handler.
        
        @param e close event (QCloseEvent)
        """
        if (
            self.process is not None and
            self.process.state() != QProcess.NotRunning
        ):
            self.process.terminate()
            QTimer.singleShot(2000, self.process.kill)
            self.process.waitForFinished(3000)
        
        self.__position = self.pos()
        
        e.accept()
        
    def show(self):
        """
        Public slot to show the dialog.
        """
        if not self.__position.isNull():
            self.move(self.__position)
        self.__resetUI()
        
        super(SvnLogBrowserDialog, self).show()
    
    def __resetUI(self):
        """
        Private method to reset the user interface.
        """
        self.fromDate.setDate(QDate.currentDate())
        self.toDate.setDate(QDate.currentDate())
        self.fieldCombo.setCurrentIndex(self.fieldCombo.findText(
            self.tr("Message")))
        self.limitSpinBox.setValue(self.vcs.getPlugin().getPreferences(
            "LogLimit"))
        self.stopCheckBox.setChecked(self.vcs.getPlugin().getPreferences(
            "StopLogOnCopy"))
        
        self.logTree.clear()
        
        self.nextButton.setEnabled(True)
        self.limitSpinBox.setEnabled(True)

    def __resizeColumnsLog(self):
        """
        Private method to resize the log tree columns.
        """
        self.logTree.header().resizeSections(QHeaderView.ResizeToContents)
        self.logTree.header().setStretchLastSection(True)
    
    def __resortLog(self):
        """
        Private method to resort the log tree.
        """
        self.logTree.sortItems(
            self.logTree.sortColumn(),
            self.logTree.header().sortIndicatorOrder())
    
    def __resizeColumnsFiles(self):
        """
        Private method to resize the changed files tree columns.
        """
        self.filesTree.header().resizeSections(QHeaderView.ResizeToContents)
        self.filesTree.header().setStretchLastSection(True)
    
    def __resortFiles(self):
        """
        Private method to resort the changed files tree.
        """
        sortColumn = self.filesTree.sortColumn()
        self.filesTree.sortItems(
            1, self.filesTree.header().sortIndicatorOrder())
        self.filesTree.sortItems(
            sortColumn, self.filesTree.header().sortIndicatorOrder())
    
    def __generateLogItem(self, author, date, message, revision, changedPaths):
        """
        Private method to generate a log tree entry.
        
        @param author author info (string)
        @param date date info (string)
        @param message text of the log message (list of strings)
        @param revision revision info (string)
        @param changedPaths list of dictionary objects containing
            info about the changed files/directories
        @return reference to the generated item (QTreeWidgetItem)
        """
        msg = []
        for line in message:
            msg.append(line.strip())
        
        itm = QTreeWidgetItem(self.logTree)
        itm.setData(0, Qt.DisplayRole, int(revision))
        itm.setData(1, Qt.DisplayRole, author)
        itm.setData(2, Qt.DisplayRole, date)
        itm.setData(3, Qt.DisplayRole, " ".join(msg))
        
        itm.setData(0, self.__messageRole, message)
        itm.setData(0, self.__changesRole, changedPaths)
        
        itm.setTextAlignment(0, Qt.AlignRight)
        itm.setTextAlignment(1, Qt.AlignLeft)
        itm.setTextAlignment(2, Qt.AlignLeft)
        itm.setTextAlignment(3, Qt.AlignLeft)
        itm.setTextAlignment(4, Qt.AlignLeft)
        
        try:
            self.__lastRev = int(revision)
        except ValueError:
            self.__lastRev = 0
        
        return itm
    
    def __generateFileItem(self, action, path, copyFrom, copyRev):
        """
        Private method to generate a changed files tree entry.
        
        @param action indicator for the change action ("A", "D" or "M")
        @param path path of the file in the repository (string)
        @param copyFrom path the file was copied from (None, string)
        @param copyRev revision the file was copied from (None, string)
        @return reference to the generated item (QTreeWidgetItem)
        """
        itm = QTreeWidgetItem(self.filesTree, [
            self.flags[action],
            path,
            copyFrom,
            copyRev,
        ])
        
        itm.setTextAlignment(3, Qt.AlignRight)
        
        return itm
    
    def __getLogEntries(self, startRev=None):
        """
        Private method to retrieve log entries from the repository.
        
        @param startRev revision number to start from (integer, string)
        """
        self.buttonBox.button(QDialogButtonBox.Close).setEnabled(False)
        self.buttonBox.button(QDialogButtonBox.Cancel).setEnabled(True)
        self.buttonBox.button(QDialogButtonBox.Cancel).setDefault(True)
        QApplication.processEvents()
        
        QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
        QApplication.processEvents()
        
        self.intercept = False
        self.process.kill()
        
        self.buf = []
        self.cancelled = False
        self.errors.clear()
        
        args = []
        args.append('log')
        self.vcs.addArguments(args, self.vcs.options['global'])
        self.vcs.addArguments(args, self.vcs.options['log'])
        args.append('--verbose')
        args.append('--limit')
        args.append('{0:d}'.format(self.limitSpinBox.value()))
        if startRev is not None:
            args.append('--revision')
            args.append('{0}:0'.format(startRev))
        if self.stopCheckBox.isChecked():
            args.append('--stop-on-copy')
        args.append(self.fname)
        
        self.process.setWorkingDirectory(self.dname)
        
        self.inputGroup.setEnabled(True)
        self.inputGroup.show()
        
        self.process.start('svn', args)
        procStarted = self.process.waitForStarted(5000)
        if not procStarted:
            self.inputGroup.setEnabled(False)
            self.inputGroup.hide()
            E5MessageBox.critical(
                self,
                self.tr('Process Generation Error'),
                self.tr(
                    'The process {0} could not be started. '
                    'Ensure, that it is in the search path.'
                ).format('svn'))
    
    def start(self, fn, isFile=False):
        """
        Public slot to start the svn log command.
        
        @param fn filename to show the log for (string)
        @keyparam isFile flag indicating log for a file is to be shown
            (boolean)
        """
        self.sbsCheckBox.setEnabled(isFile)
        self.sbsCheckBox.setVisible(isFile)
        
        self.errorGroup.hide()
        QApplication.processEvents()
        
        self.__initData()
        
        self.filename = fn
        self.dname, self.fname = self.vcs.splitPath(fn)
        
        self.activateWindow()
        self.raise_()
        
        self.logTree.clear()
        self.__started = True
        self.__getLogEntries()
    
    def __procFinished(self, exitCode, exitStatus):
        """
        Private slot connected to the finished signal.
        
        @param exitCode exit code of the process (integer)
        @param exitStatus exit status of the process (QProcess.ExitStatus)
        """
        self.__processBuffer()
        self.__finish()
    
    def __finish(self):
        """
        Private slot called when the process finished or the user pressed the
        button.
        """
        if (
            self.process is not None and
            self.process.state() != QProcess.NotRunning
        ):
            self.process.terminate()
            QTimer.singleShot(2000, self.process.kill)
            self.process.waitForFinished(3000)
        
        QApplication.restoreOverrideCursor()
        
        self.buttonBox.button(QDialogButtonBox.Close).setEnabled(True)
        self.buttonBox.button(QDialogButtonBox.Cancel).setEnabled(False)
        self.buttonBox.button(QDialogButtonBox.Close).setDefault(True)
        
        self.inputGroup.setEnabled(False)
        self.inputGroup.hide()
        
        while self.__finishCallbacks:
            self.__finishCallbacks.pop(0)()
    
    def __processBuffer(self):
        """
        Private method to process the buffered output of the svn log command.
        """
        noEntries = 0
        log = {"message": []}
        changedPaths = []
        for s in self.buf:
            if self.rx_rev1.exactMatch(s):
                log["revision"] = self.rx_rev.cap(1)
                log["author"] = self.rx_rev.cap(2)
                log["date"] = self.rx_rev.cap(3)
                # number of lines is ignored
            elif self.rx_rev2.exactMatch(s):
                log["revision"] = self.rx_rev2.cap(1)
                log["author"] = self.rx_rev2.cap(2)
                log["date"] = " ".join(self.rx_rev2.cap(3).split()[:2])
                # number of lines is ignored
            elif self.rx_flags1.exactMatch(s):
                changedPaths.append({
                    "action":
                    self.rx_flags1.cap(1).strip(),
                    "path":
                    self.rx_flags1.cap(2).strip(),
                    "copyfrom_path":
                    self.rx_flags1.cap(3).strip(),
                    "copyfrom_revision":
                    self.rx_flags1.cap(4).strip(),
                })
            elif self.rx_flags2.exactMatch(s):
                changedPaths.append({
                    "action":
                    self.rx_flags2.cap(1).strip(),
                    "path":
                    self.rx_flags2.cap(2).strip(),
                    "copyfrom_path": "",
                    "copyfrom_revision": "",
                })
            elif self.rx_sep1.exactMatch(s) or self.rx_sep2.exactMatch(s):
                if len(log) > 1:
                    self.__generateLogItem(
                        log["author"], log["date"], log["message"],
                        log["revision"], changedPaths)
                    dt = QDate.fromString(log["date"], Qt.ISODate)
                    if (
                        not self.__maxDate.isValid() and
                        not self.__minDate.isValid()
                    ):
                        self.__maxDate = dt
                        self.__minDate = dt
                    else:
                        if self.__maxDate < dt:
                            self.__maxDate = dt
                        if self.__minDate > dt:
                            self.__minDate = dt
                    noEntries += 1
                    log = {"message": []}
                    changedPaths = []
            else:
                if s.strip().endswith(":") or not s.strip():
                    continue
                else:
                    log["message"].append(s)
        
        self.__resizeColumnsLog()
        self.__resortLog()
        
        if self.__started:
            self.logTree.setCurrentItem(self.logTree.topLevelItem(0))
            self.__started = False
        
        if noEntries < self.limitSpinBox.value() and not self.cancelled:
            self.nextButton.setEnabled(False)
            self.limitSpinBox.setEnabled(False)
        
        self.__filterLogsEnabled = False
        self.fromDate.setMinimumDate(self.__minDate)
        self.fromDate.setMaximumDate(self.__maxDate)
        self.fromDate.setDate(self.__minDate)
        self.toDate.setMinimumDate(self.__minDate)
        self.toDate.setMaximumDate(self.__maxDate)
        self.toDate.setDate(self.__maxDate)
        self.__filterLogsEnabled = True
        self.__filterLogs()
    
    def __readStdout(self):
        """
        Private slot to handle the readyReadStandardOutput signal.
        
        It reads the output of the process and inserts it into a buffer.
        """
        self.process.setReadChannel(QProcess.StandardOutput)
        
        while self.process.canReadLine():
            line = str(self.process.readLine(),
                       Preferences.getSystem("IOEncoding"),
                       'replace')
            self.buf.append(line)
    
    def __readStderr(self):
        """
        Private slot to handle the readyReadStandardError signal.
        
        It reads the error output of the process and inserts it into the
        error pane.
        """
        if self.process is not None:
            self.errorGroup.show()
            s = str(self.process.readAllStandardError(),
                    Preferences.getSystem("IOEncoding"),
                    'replace')
            self.errors.insertPlainText(s)
            self.errors.ensureCursorVisible()
    
    def __diffRevisions(self, rev1, rev2):
        """
        Private method to do a diff of two revisions.
        
        @param rev1 first revision number (integer)
        @param rev2 second revision number (integer)
        """
        if self.sbsCheckBox.isEnabled() and self.sbsCheckBox.isChecked():
            self.vcs.svnSbsDiff(self.filename,
                                revisions=(str(rev1), str(rev2)))
        else:
            if self.diff is None:
                from .SvnDiffDialog import SvnDiffDialog
                self.diff = SvnDiffDialog(self.vcs)
            self.diff.show()
            self.diff.raise_()
            self.diff.start(self.filename, [rev1, rev2])
    
    def on_buttonBox_clicked(self, button):
        """
        Private slot called by a button of the button box clicked.
        
        @param button button that was clicked (QAbstractButton)
        """
        if button == self.buttonBox.button(QDialogButtonBox.Close):
            self.close()
        elif button == self.buttonBox.button(QDialogButtonBox.Cancel):
            self.cancelled = True
            self.__finish()
    
    @pyqtSlot(QTreeWidgetItem, QTreeWidgetItem)
    def on_logTree_currentItemChanged(self, current, previous):
        """
        Private slot called, when the current item of the log tree changes.
        
        @param current reference to the new current item (QTreeWidgetItem)
        @param previous reference to the old current item (QTreeWidgetItem)
        """
        if current is not None:
            self.messageEdit.clear()
            for line in current.data(0, self.__messageRole):
                self.messageEdit.append(line.strip())
            
            self.filesTree.clear()
            changes = current.data(0, self.__changesRole)
            if len(changes) > 0:
                for change in changes:
                    self.__generateFileItem(
                        change["action"], change["path"],
                        change["copyfrom_path"],
                        change["copyfrom_revision"])
                self.__resizeColumnsFiles()
            self.__resortFiles()
        
        self.diffPreviousButton.setEnabled(
            current != self.logTree.topLevelItem(
                self.logTree.topLevelItemCount() - 1))
        
        # Highlight the current entry using a bold font
        for col in range(self.logTree.columnCount()):
            current and current.setFont(col, self.__logTreeBoldFont)
            previous and previous.setFont(col, self.__logTreeNormalFont)
        
        # set the state of the up and down buttons
        self.upButton.setEnabled(
            current is not None and
            self.logTree.indexOfTopLevelItem(current) > 0)
        self.downButton.setEnabled(
            current is not None and
            int(current.text(0)) > 1)
    
    @pyqtSlot()
    def on_logTree_itemSelectionChanged(self):
        """
        Private slot called, when the selection has changed.
        """
        self.diffRevisionsButton.setEnabled(
            len(self.logTree.selectedItems()) == 2)
    
    @pyqtSlot()
    def on_nextButton_clicked(self):
        """
        Private slot to handle the Next button.
        """
        if self.__lastRev > 1:
            self.__getLogEntries(self.__lastRev - 1)
    
    @pyqtSlot()
    def on_diffPreviousButton_clicked(self):
        """
        Private slot to handle the Diff to Previous button.
        """
        itm = self.logTree.currentItem()
        if itm is None:
            self.diffPreviousButton.setEnabled(False)
            return
        rev2 = int(itm.text(0))
        
        itm = self.logTree.topLevelItem(
            self.logTree.indexOfTopLevelItem(itm) + 1)
        if itm is None:
            self.diffPreviousButton.setEnabled(False)
            return
        rev1 = int(itm.text(0))
        
        self.__diffRevisions(rev1, rev2)
    
    @pyqtSlot()
    def on_diffRevisionsButton_clicked(self):
        """
        Private slot to handle the Compare Revisions button.
        """
        items = self.logTree.selectedItems()
        if len(items) != 2:
            self.diffRevisionsButton.setEnabled(False)
            return
        
        rev2 = int(items[0].text(0))
        rev1 = int(items[1].text(0))
        
        self.__diffRevisions(min(rev1, rev2), max(rev1, rev2))
    
    @pyqtSlot(QDate)
    def on_fromDate_dateChanged(self, date):
        """
        Private slot called, when the from date changes.
        
        @param date new date (QDate)
        """
        self.__filterLogs()
    
    @pyqtSlot(QDate)
    def on_toDate_dateChanged(self, date):
        """
        Private slot called, when the from date changes.
        
        @param date new date (QDate)
        """
        self.__filterLogs()
    
    @pyqtSlot(str)
    def on_fieldCombo_activated(self, txt):
        """
        Private slot called, when a new filter field is selected.
        
        @param txt text of the selected field (string)
        """
        self.__filterLogs()
    
    @pyqtSlot(str)
    def on_rxEdit_textChanged(self, txt):
        """
        Private slot called, when a filter expression is entered.
        
        @param txt filter expression (string)
        """
        self.__filterLogs()
    
    def __filterLogs(self):
        """
        Private method to filter the log entries.
        """
        if self.__filterLogsEnabled:
            from_ = self.fromDate.date().toString("yyyy-MM-dd")
            to_ = self.toDate.date().addDays(1).toString("yyyy-MM-dd")
            txt = self.fieldCombo.currentText()
            if txt == self.tr("Author"):
                fieldIndex = 1
                searchRx = QRegExp(self.rxEdit.text(), Qt.CaseInsensitive)
            elif txt == self.tr("Revision"):
                fieldIndex = 0
                txt = self.rxEdit.text()
                if txt.startswith("^"):
                    searchRx = QRegExp(
                        r"^\s*{0}".format(txt[1:]), Qt.CaseInsensitive)
                else:
                    searchRx = QRegExp(txt, Qt.CaseInsensitive)
            else:
                fieldIndex = 3
                searchRx = QRegExp(self.rxEdit.text(), Qt.CaseInsensitive)
            
            currentItem = self.logTree.currentItem()
            for topIndex in range(self.logTree.topLevelItemCount()):
                topItem = self.logTree.topLevelItem(topIndex)
                if (
                    topItem.text(2) <= to_ and
                    topItem.text(2) >= from_ and
                    searchRx.indexIn(topItem.text(fieldIndex)) > -1
                ):
                    topItem.setHidden(False)
                    if topItem is currentItem:
                        self.on_logTree_currentItemChanged(topItem, None)
                else:
                    topItem.setHidden(True)
                    if topItem is currentItem:
                        self.messageEdit.clear()
                        self.filesTree.clear()
    
    @pyqtSlot(bool)
    def on_stopCheckBox_clicked(self, checked):
        """
        Private slot called, when the stop on copy/move checkbox is clicked.
        
        @param checked flag indicating the checked state (boolean)
        """
        self.vcs.getPlugin().setPreferences("StopLogOnCopy",
                                            self.stopCheckBox.isChecked())
        self.nextButton.setEnabled(True)
        self.limitSpinBox.setEnabled(True)
    
    @pyqtSlot()
    def on_upButton_clicked(self):
        """
        Private slot to move the current item up one entry.
        """
        itm = self.logTree.itemAbove(self.logTree.currentItem())
        if itm:
            self.logTree.setCurrentItem(itm)
    
    @pyqtSlot()
    def on_downButton_clicked(self):
        """
        Private slot to move the current item down one entry.
        """
        itm = self.logTree.itemBelow(self.logTree.currentItem())
        if itm:
            self.logTree.setCurrentItem(itm)
        else:
            # load the next bunch and try again
            self.__addFinishCallback(self.on_downButton_clicked)
            self.on_nextButton_clicked()
    
    def on_passwordCheckBox_toggled(self, isOn):
        """
        Private slot to handle the password checkbox toggled.
        
        @param isOn flag indicating the status of the check box (boolean)
        """
        if isOn:
            self.input.setEchoMode(QLineEdit.Password)
        else:
            self.input.setEchoMode(QLineEdit.Normal)
    
    @pyqtSlot()
    def on_sendButton_clicked(self):
        """
        Private slot to send the input to the subversion process.
        """
        inputTxt = self.input.text()
        inputTxt += os.linesep
        
        if self.passwordCheckBox.isChecked():
            self.errors.insertPlainText(os.linesep)
            self.errors.ensureCursorVisible()
        else:
            self.errors.insertPlainText(inputTxt)
            self.errors.ensureCursorVisible()
        self.errorGroup.show()
        
        self.process.write(strToQByteArray(inputTxt))
        
        self.passwordCheckBox.setChecked(False)
        self.input.clear()
    
    def on_input_returnPressed(self):
        """
        Private slot to handle the press of the return key in the input field.
        """
        self.intercept = True
        self.on_sendButton_clicked()
    
    def keyPressEvent(self, evt):
        """
        Protected slot to handle a key press event.
        
        @param evt the key press event (QKeyEvent)
        """
        if self.intercept:
            self.intercept = False
            evt.accept()
            return
        super(SvnLogBrowserDialog, self).keyPressEvent(evt)
