# Copyright 2015, Tresys Technology, LLC
#
# This file is part of SETools.
#
# SETools is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as
# published by the Free Software Foundation, either version 2.1 of
# the License, or (at your option) any later version.
#
# SETools is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with SETools.  If not, see
# <http://www.gnu.org/licenses/>.
#

import logging

from PyQt5.QtCore import Qt, QSortFilterProxyModel, QStringListModel
from PyQt5.QtGui import QPalette, QTextCursor
from PyQt5.QtWidgets import QCompleter, QHeaderView, QWidget
from setools import TERuleQuery

from ..widget import SEToolsWidget
from .rulemodels import TERuleListModel
from .models import PermListModel, SEToolsListModel


class TERuleQueryTab(SEToolsWidget, QWidget):
    def __init__(self, tab, policy):
        super(TERuleQueryTab, self).__init__(tab)
        self.log = logging.getLogger(self.__class__.__name__)
        self.policy = policy
        self.query = TERuleQuery(policy)
        self.tab = tab
        self.setupUi()

    def setupUi(self):
        self.load_ui("terulequery.ui")

        # set up source/target/default autocompletion
        completion_list = [str(t) for t in self.policy.types()]
        completion_list.extend(str(a) for a in self.policy.typeattributes())
        completer_model = QStringListModel(self)
        completer_model.setStringList(sorted(completion_list))
        self.type_completion = QCompleter()
        self.type_completion.setModel(completer_model)
        self.source.setCompleter(self.type_completion)
        self.target.setCompleter(self.type_completion)

        # setup indications of errors on source/target
        self.orig_palette = self.source.palette()
        self.error_palette = self.source.palette()
        self.error_palette.setColor(QPalette.Base, Qt.red)
        self.clear_source_error()
        self.clear_target_error()
        self.clear_default_error()

        # populate class list
        self.class_model = SEToolsListModel(self)
        self.class_model.item_list = sorted(self.policy.classes())
        self.tclass.setModel(self.class_model)

        # populate perm list
        self.perms_model = PermListModel(self, self.policy)
        self.perms.setModel(self.perms_model)

        # set up results
        self.table_results_model = TERuleListModel(self)
        self.sort_proxy = QSortFilterProxyModel(self)
        self.sort_proxy.setSourceModel(self.table_results_model)
        self.table_results.setModel(self.sort_proxy)
        headerview = self.table_results.horizontalHeader()
        headerview.setSectionResizeMode(0, QHeaderView.ResizeToContents)
        headerview.setSectionResizeMode(1, QHeaderView.ResizeToContents)
        headerview.setSectionResizeMode(2, QHeaderView.ResizeToContents)
        headerview.setSectionResizeMode(3, QHeaderView.ResizeToContents)
        headerview.setSectionResizeMode(4, QHeaderView.Stretch)
        headerview.setSectionResizeMode(5, QHeaderView.ResizeToContents)

        # check expanders to make sure the display
        # is consistent with the initial .ui state
        self.toggle_criteria_frame()
        self.toggle_results_frame()
        self.toggle_notes_frame()

        # connect signals
        self.buttonBox.clicked.connect(self.run)
        self.source.textEdited.connect(self.clear_source_error)
        self.source.editingFinished.connect(self.set_source)
        self.target.textEdited.connect(self.clear_target_error)
        self.target.editingFinished.connect(self.set_target)
        self.source_regex.toggled.connect(self.set_source)
        self.target_regex.toggled.connect(self.set_target)
        self.tclass.selectionModel().selectionChanged.connect(self.set_tclass)
        self.clear_class.clicked.connect(self.clear_tclass_selection)
        self.perms.selectionModel().selectionChanged.connect(self.set_perms)
        self.clear_perms.clicked.connect(self.clear_perms_selection)
        self.criteria_expander.clicked.connect(self.toggle_criteria_frame)
        self.results_expander.clicked.connect(self.toggle_results_frame)
        self.notes_expander.clicked.connect(self.toggle_notes_frame)

    #
    # Source criteria
    #

    def clear_source_error(self):
        self.source.setToolTip("Match the source type/attribute of the rule.")
        self.source.setPalette(self.orig_palette)

    def set_source(self):
        self.query.source_regex = self.source_regex.isChecked()

        try:
            self.query.source = self.source.text()
        except Exception as ex:
            self.source.setToolTip("Error: " + str(ex))
            self.source.setPalette(self.error_palette)

    #
    # Target criteria
    #

    def clear_target_error(self):
        self.target.setToolTip("Match the target type/attribute of the rule.")
        self.target.setPalette(self.orig_palette)

    def set_target(self):
        self.query.target_regex = self.target_regex.isChecked()

        try:
            self.query.target = self.target.text()
        except Exception as ex:
            self.target.setToolTip("Error: " + str(ex))
            self.target.setPalette(self.error_palette)

    #
    # Class criteria
    #

    def clear_tclass_selection(self):
        self.tclass.selectionModel().clearSelection()

    def set_tclass(self):
        selected_classes = []
        for index in self.tclass.selectionModel().selectedIndexes():
            selected_classes.append(self.class_model.data(index, Qt.UserRole))

        self.query.tclass = selected_classes
        self.perms_model.set_classes(selected_classes)

    #
    # Permissions criteria
    #

    def clear_perms_selection(self):
        self.perms.selectionModel().clearSelection()

    def set_perms(self):
        selected_perms = []
        for index in self.perms.selectionModel().selectedIndexes():
            selected_perms.append(self.perms_model.data(index, Qt.UserRole))

        self.query.perms = selected_perms

    #
    # Results runner
    #

    def run(self, button):
        # right now there is only one button.
        rule_types = []

        if self.allow.isChecked():
            rule_types.append("allow")
        if self.auditallow.isChecked():
            rule_types.append("auditallow")
        if self.neverallow.isChecked():
            rule_types.append("neverallow")
        if self.dontaudit.isChecked():
            rule_types.append("dontaudit")
        if self.type_transition.isChecked():
            rule_types.append("type_transition")
        if self.type_member.isChecked():
            rule_types.append("type_member")
        if self.type_change.isChecked():
            rule_types.append("type_change")

        self.query.ruletype = rule_types
        self.query.source_indirect = self.source_indirect.isChecked()
        self.query.target_indirect = self.target_indirect.isChecked()

        # update results table
        results = list(self.query.results())
        self.table_results_model.set_rules(results)

        # update raw results
        self.raw_results.clear()
        for line in results:
            self.raw_results.appendPlainText(str(line))

        self.raw_results.moveCursor(QTextCursor.Start)

    #
    # Section expander handlers
    #

    def toggle_criteria_frame(self):
        if self.criteria_expander.isChecked():
            self.criteria_frame.show()
        else:
            self.criteria_frame.hide()

    def toggle_results_frame(self):
        if self.results_expander.isChecked():
            self.results_frame.show()
        else:
            self.results_frame.hide()

    def toggle_notes_frame(self):
        if self.notes_expander.isChecked():
            self.notes.show()
        else:
            self.notes.hide()