#!/usr/bin/python
# -*- coding: utf-8 -*-

import sys, os

from PyQt5 import QtCore
from PyQt5.QtGui import QFont, QSyntaxHighlighter
from PyQt5.QtWidgets import QWidget, QLabel, QHBoxLayout, QVBoxLayout, QSplitter, QListView, QAbstractItemView

import markdown
import re
import json


class Summary(QWidget):
   def __init__(self, core):
      super(Summary, self).__init__()
      self.core = core

      sum_json = open(os.path.join(self.core.cwd,'.config/summary.json')).read()
      self.sum = json.loads(sum_json)

      vbox = QVBoxLayout()
      vbox.setContentsMargins(0,0,0,0)

      self.list = SummaryList(self)
      vbox.addWidget(self.list)

      # self.actions = SummaryActions(self)
      # self.addWidget(self.actions)

      self.setLayout(vbox)

class SumListModel(QtCore.QAbstractListModel):
   dragDropFinished = QtCore.pyqtSignal()
   def __init__(self,sum):
      QtCore.QAbstractItemModel.__init__(self)
      self.nodes = ['node0', 'node1', 'node2', 'node3', 'node4', 'node5']
      self.lastDroppedItems = []
      self.pendingRemoveRowsAfterDrop = False

   def rowForItem(self, text):
      '''
      rowForItem method returns the row corresponding to the passed in item
      or None if no such item exists in the model
      '''
      try:
         row = self.nodes.index(text)
      except ValueError:
         return None
      return row

   def index(self, row, column, parent):
      if row < 0 or row >= len(self.nodes):
         return QtCore.QModelIndex()
      return self.createIndex(row, column)

   def parent(self, index):
      return QtCore.QModelIndex()

   def rowCount(self, index):
      if index.isValid():
         return 0
      return len(self.nodes)

   def data(self, index, role):
      if not index.isValid():
         return None
      if role == QtCore.Qt.DisplayRole:
         row = index.row()
         if row < 0 or row >= len(self.nodes):
             return None
         return self.nodes[row]
      else:
         return None

   def supportedDropActions(self):
      return QtCore.Qt.MoveAction

   def flags(self, index):
      if not index.isValid():
         return QtCore.Qt.ItemIsEnabled
      return QtCore.Qt.ItemIsEnabled | QtCore.Qt.ItemIsSelectable | \
            QtCore.Qt.ItemIsDragEnabled | QtCore.Qt.ItemIsDropEnabled

   def insertRows(self, row, count, index):
      if index.isValid():
         return False
      if count <= 0:
         return False
      # inserting 'count' empty rows starting at 'row'
      self.beginInsertRows(QtCore.QModelIndex(), row, row + count - 1)
      for i in range(0, count):
         self.nodes.insert(row + i, '')
      self.endInsertRows()
      return True

   def removeRows(self, row, count, index):
      if index.isValid():
         return False
      if count <= 0:
         return False
      num_rows = self.rowCount(QtCore.QModelIndex())
      self.beginRemoveRows(QtCore.QModelIndex(), row, row + count - 1)
      for i in range(count, 0, -1):
         self.nodes.pop(row - i + 1)
      self.endRemoveRows()

      if self.pendingRemoveRowsAfterDrop:
         '''
         If we got here, it means this call to removeRows is the automatic
         'cleanup' action after drag-n-drop performed by Qt
         '''
         self.pendingRemoveRowsAfterDrop = False
         self.dragDropFinished.emit()

      return True

   def setData(self, index, value, role):
      if not index.isValid():
         return False
      if index.row() < 0 or index.row() > len(self.nodes):
         return False
      self.nodes[index.row()] = str(value)
      self.dataChanged.emit(index, index)
      return True

   def mimeTypes(self):
      return ['application/vnd.treeviewdragdrop.list']

   def mimeData(self, indexes):
      mimedata = QtCore.QMimeData()
      encoded_data = QtCore.QByteArray()
      stream = QtCore.QDataStream(encoded_data, QtCore.QIODevice.WriteOnly)
      for index in indexes:
         if index.isValid():
             text = self.data(index, 0)
      stream << QtCore.QByteArray(text.encode('utf-8'))
      mimedata.setData('application/vnd.treeviewdragdrop.list', encoded_data)
      return mimedata

   def dropMimeData(self, data, action, row, column, parent):
      if action == QtCore.Qt.IgnoreAction:
         return True
      if not data.hasFormat('application/vnd.treeviewdragdrop.list'):
         return False
      if column > 0:
         return False

      num_rows = self.rowCount(QtCore.QModelIndex())
      if num_rows <= 0:
         return False

      if row < 0:
         if parent.isValid():
            row = parent.row()
         else:
            return False

      encoded_data = data.data('application/vnd.treeviewdragdrop.list')
      stream = QtCore.QDataStream(encoded_data, QtCore.QIODevice.ReadOnly)

      new_items = []
      rows = 0
      while not stream.atEnd():
         text = QtCore.QByteArray()
         stream >> text
         text = bytes(text).decode('utf-8')
         index = self.nodes.index(text)
         new_items.append((text, index))
         rows += 1

      self.lastDroppedItems = []
      for (text, index) in new_items:
         target_row = row
         if index < row:
            target_row += 1
         self.beginInsertRows(QtCore.QModelIndex(), target_row, target_row)
         self.nodes.insert(target_row, text)
         self.endInsertRows()
         self.lastDroppedItems.append(text)
         row += 1

      self.pendingRemoveRowsAfterDrop = True
      return True

class SumListSelectionModel(QtCore.QItemSelectionModel):
   def __init__(self, parent=None):
      QtCore.QItemSelectionModel.__init__(self, parent)

   def onModelItemsReordered(self):
      new_selection = QtCore.QItemSelection()
      new_index = QtCore.QModelIndex()
      for item in self.model().lastDroppedItems:
         row = self.model().rowForItem(item)
         if row is None:
            continue
         new_index = self.model().index(row, 0, QtCore.QModelIndex())
         new_selection.select(new_index, new_index)

      self.clearSelection()
      flags = QtCore.QItemSelectionModel.ClearAndSelect | \
              QtCore.QItemSelectionModel.Rows | \
              QtCore.QItemSelectionModel.Current
      self.select(new_selection, flags)
      self.setCurrentIndex(new_index, flags)

class SummaryList(QListView):
   def __init__(self,prt):
      super(SummaryList, self).__init__()
      print("list")
      self.prt = prt
      model = SumListModel(sum)
      selectionModel = SumListSelectionModel(model)
      model.dragDropFinished.connect(selectionModel.onModelItemsReordered)
      self.setModel(model)
      self.setSelectionModel(selectionModel)
      self.setDragDropMode(QAbstractItemView.InternalMove)
      self.setDragDropOverwriteMode(False)


class SummaryActions(QWidget):
   def __init__(self,sum):
      print("actions")
      # for p in self.sum:

# class SummaryActions():
#    def

class ContentStack(QWidget):
   def __init__(self, core):
      super(ContentStack, self).__init__()

      # self.grid = QGridLayout()
      hbox = QHBoxLayout()
      hbox.setContentsMargins(0,0,0,0)
      self.setLayout(hbox)

      hsplitter = QSplitter(QtCore.Qt.Horizontal)

      self.summary = Summary(core)
      hsplitter.addWidget(self.summary)

      self.mdsource = QLabel("Content (markdown src).")
      hsplitter.addWidget(self.mdsource)

      self.mdpreview = QLabel("Content (markdown preview).")
      hsplitter.addWidget(self.mdpreview)

      hbox.addWidget(hsplitter)