#!/usr/bin/env python3

from birdvisu.annotations import AnnotatedTopology, AnnotatorID
from birdvisu.annotations.analysis import TopologyDifference, ShortestPathTree
from birdvisu.ospfsock import BirdSocketConnection
from birdvisu.providers import BirdSocketTopologyProvider, OspfFileTopologyProvider, OspfFileParseError
from birdvisu.topo_v3 import TopologyV3, VertexID

from collections import defaultdict
from enum import Enum, auto
from ipaddress import IPv4Address
from PySide6 import QtCore, QtGui, QtWidgets
from PySide6.QtCore import Slot
from random import randint
import sys

app = QtWidgets.QApplication([])


class MyGraphicsRectItem(QtWidgets.QGraphicsRectItem):
	def __init__(self, nei, shapes, *a, **kwa):
		self.nei = nei
		self.shapes = shapes
		return super().__init__(*a, **kwa)
	#def itemChange(self, change, val):
	#       return super().itemChange(change, val)
	def mouseMoveEvent(self, evt):
		vtxid = self.data(0)
		for e in self.nei[vtxid]:
			x1 = self.x()
			y1 = self.y()
			other = e.source if e.source != vtxid else e.target
			x2 = self.shapes[other].x()
			y2 = self.shapes[other].y()
			qlinef = QtCore.QLineF(x1, y1, x2, y2)
			self.shapes[e].setLine(qlinef)
		return super().mouseMoveEvent(evt)

class BirdTopologyLoader(QtWidgets.QDialog):
	def __init__(self, *a, **kwa):
		super().__init__(*a, **kwa)
		self.setModal(True)
		self.result_ = (None, None, None)
		outer = QtWidgets.QVBoxLayout(self)
		# Area
		inner = QtWidgets.QHBoxLayout()
		inner.addWidget(QtWidgets.QLabel('Area:'))
		line = QtWidgets.QLineEdit(self)
		line.setText('-1')
		self.line = line
		inner.addWidget(line)
		outer.addLayout(inner)

		inner = QtWidgets.QHBoxLayout()
		inner.addWidget(QtWidgets.QLabel('Instance:'))
		combo = QtWidgets.QComboBox()
		combo.addItems(self.get_instances())
		self.combo = combo
		inner.addWidget(combo)
		outer.addLayout(inner)

		inner = QtWidgets.QHBoxLayout()
		inner.addWidget(QtWidgets.QLabel('Protocol:'))
		combo = QtWidgets.QComboBox()
		combo.addItems(['Guess!', 'OSPFv2', 'OSPFv3'])
		self.combo2 = combo
		inner.addWidget(combo)
		outer.addLayout(inner)

		buttons = QtWidgets.QDialogButtonBox(QtWidgets.QDialogButtonBox.Ok | QtWidgets.QDialogButtonBox.Cancel)
		buttons.accepted.connect(self.saveResult)
		buttons.accepted.connect(self.accept)
		buttons.rejected.connect(self.reject)
		outer.addWidget(buttons)

	@Slot()
	def saveResult(self):
		try:
			area = int(self.line.text())
		except ValueError:
			area = int(IPv4Address(self.line.text()))
		if area == -1: area = None
		inst = self.combo.currentText()
		proto = {
			'OSPFv2': 2,
			'OSPFv3': 3,
			'Guess!': None,
			}[self.combo2.currentText()]
		self.result_ = (area, inst, proto)
	
	def get_instances(self):
		# Our code is stupid, so we initialise a BirdSocketTopologyProvider just to get instances and then drop it.
		prov = BirdSocketTopologyProvider()
		bird = BirdSocketConnection()
		return prov.find_running_ospf(bird)


class MainWindow(QtWidgets.QMainWindow):
	class Tool(Enum):
		MoveTopology = auto()
		ShortestPath = auto()

	def __init__(self, *a, **kwa):
		super().__init__(*a, **kwa)
		self.ref_topo_provider = None
		self.cur_topo_provider = None
		self.annotators = self.get_annotators()
		self.annot_topo = None
		self.highlighter = None
		self.tool = self.Tool.MoveTopology
		self.scene = QtWidgets.QGraphicsScene()
		self.view = QtWidgets.QGraphicsView(self.scene)
		self.view.setDragMode(self.view.DragMode.ScrollHandDrag)
		self.setCentralWidget(self.view)
		self.statusbar = self.statusBar()
		self.statusbar.showMessage('Hello!')

		self.menubar = self.menuBar()
		mode_menu = self.menubar.addMenu('&Mode')
		short_path_act = QtGui.QAction("Sh. path &DAG", self)
		short_path_act.triggered.connect(self.shortestPathMode)
		mode_menu.addAction(short_path_act)

		topo_menu = self.menubar.addMenu('&Topology')
		open_ref_act = QtGui.QAction("&Load reference", self)
		open_ref_act.triggered.connect(self.openRefTopology)
		topo_menu.addAction(open_ref_act)

		cur_topo_menu = topo_menu.addMenu("Load &current")
		running_bird_act = QtGui.QAction('&BIRD', self)
		running_bird_act.triggered.connect(self.curTopologyFromBird)
		cur_topo_menu.addAction(running_bird_act)
		from_file_act = QtGui.QAction('&from file', self)
		from_file_act.triggered.connect(self.curTopologyFromFile)
		cur_topo_menu.addAction(from_file_act)

		refresh_act = QtGui.QAction("&Refresh", self)
		refresh_act.triggered.connect(self.refreshTopologies)
		topo_menu.addAction(refresh_act)

	def get_annotators(self):
		return [
			AnnotatorID(TopologyDifference),
			AnnotatorID(ShortestPathTree, (VertexID(
				family=None,
				is_router=True,
				address=None,
				router_id=int(IPv4Address('172.23.100.10')),
				dr_id=None,
				discriminator=None
				), 'current')),
			]

	@Slot()
	def shortestPathMode(self):
		self.tool = self.Tool.ShortestPath
	
	@Slot()
	def openRefTopology(self):
		filename = QtWidgets.QFileDialog.getOpenFileName(self, 'Open reference topology', '.', 'OSPF files(*.ospf);;All files(*)')[0]
		if filename == '': return # Do nothing
		self.ref_topo_provider = OspfFileTopologyProvider(filename)
		try:
			ref_topo = self.ref_topo_provider.get_topology()
		except OspfFileParseError as e:
			warning = QtWidgets.QMessageBox.critical(self, "Bad reference topology", f"The reference topology seems to be malformed: {e}.\nPlease select a valid reference topology.")
			self.ref_topo_provider = None
			return
		self.refreshTopologies()
		
	@Slot()
	def curTopologyFromBird(self):
		loader = BirdTopologyLoader(self)
		loader.exec()
		area, instance, version = loader.result_
		self.cur_topo_provider = BirdSocketTopologyProvider(instance=instance, area=area, version=version)
		try:
			cur_topo = self.cur_topo_provider.get_topology()
		except OspfFileParseError as e:
			warning = QtWidgets.QMessageBox.critical(self, "Bad current topology", f"The current topology seems to be malformed: {e}.\nPlease select a valid topology.")
			self.cur_topo_provider = None
			return
		self.refreshTopologies()

	@Slot()
	def curTopologyFromFile(self):
		filename = QtWidgets.QFileDialog.getOpenFileName(self, 'Open current topology', '.', 'OSPF files(*.ospf);;All files(*)')[0]
		if filename == '': return # Do nothing
		self.cur_topo_provider = OspfFileTopologyProvider(filename)
		try:
			cur_topo = self.cur_topo_provider.get_topology()
		except OspfFileParseError as e:
			warning = QtWidgets.QMessageBox.critical(self, "Bad current topology", f"The current topology seems to be malformed: {e}.\nPlease select a valid topology.")
			self.cur_topo_provider = None
			return
		self.refreshTopologies()

	@Slot()
	def refreshTopologies(self):
		# Pre-checks:
		msg = ''
		if self.ref_topo_provider is None: msg += 'Please select reference topology. '
		if self.cur_topo_provider is None: msg += 'Please select current topology. '
		if msg:
			self.statusbar.showMessage(msg)
			# Nothing more to do.
			return
		# We just drop anything we had before, since we will be re-reading all the files.
		try:
			ref_topo = self.ref_topo_provider.get_topology()
		except OspfFileParseError as e:
			warning = QtWidgets.QMessageBox.critical(self, "Bad reference topology", f"The reference topology seems to be malformed: {e}.\nPlease select a valid reference topology.")
			self.ref_topo_provider = None
			return
		try:
			cur_topo = self.cur_topo_provider.get_topology()
		except OspfFileParseError as e:
			warning = QtWidgets.QMessageBox.critical(self, "Bad current topology", f"The current topology seems to be malformed: {e}.\nPlease select a valid topology.")
			self.cur_topo_provider = None
			return
		self.scene.clear()
		combined_topology = TopologyV3.combine_topologies(reference=ref_topo, current=cur_topo)
		combined_topology.freeze()
		self.annot_topo = AnnotatedTopology(combined_topology)
		for ann_id in self.annotators:
			self.annot_topo.run_annotator(ann_id)
		# Draw it
		self.set_current_highlighter()
		self.ad_hoc_draw_visu()
	
	def set_current_highlighter(self):
		# TODO!
		self.highlighter = self.annotators[-1]
	
	def ad_hoc_draw_visu(self):
		shapes = dict()
		self.nei = defaultdict(lambda: [])
		for k, v in self.annot_topo.topology.vertices.items():
			size = 30 if k.is_router else 10
			x, y = randint(0, 1920), randint(0, 1080)
			shape = MyGraphicsRectItem(self.nei, shapes, -size/2, -size/2, size, size)
			shape.setPos(x,y)
			# TODO:brush
			label_text = str(IPv4Address(k.router_id)) if k.is_router else str(k.address) # Surprisingly works for all the possible addresses.
			label = QtWidgets.QGraphicsSimpleTextItem(label_text, parent=shape)
			label.setY(size*0.8)
			text_width = label.boundingRect().width()
			label.setX(-text_width/2)
			shape.setData(0, k)
			shape.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable | QtWidgets.QGraphicsItem.ItemIsSelectable)
			shapes[k] = shape

		for e in self.annot_topo.topology.edges:
			start = shapes[e.source].pos()
			end = shapes[e.target].pos()
			qlinef = QtCore.QLineF(start, end)
			line = QtWidgets.QGraphicsLineItem(qlinef)
			line.setData(0, e)
			self.nei[e.source].append(e)
			self.nei[e.target].append(e)
			shapes[e] = line
		if self.highlighter is not None and self.highlighter in self.annot_topo.annotations:
			ann = self.annot_topo.annotations[self.highlighter]
			for shk in ann.for_vertex.keys() | ann.for_edge.keys():
				pen = QtGui.QPen(QtGui.QColor('blue'))
				pen.setWidth(pen.width() * 3)
				c = pen.color()
				c.setAlpha(128)
				pen.setColor(c)
				shapes[shk].setPen(pen)
			# FIXME: also color edges in opposite direction
		for sh in shapes.values(): self.scene.addItem(sh)

main_window = MainWindow()
main_window.show()
app.exec()