Padding, changing key symbols, size improvements, etc
[ejpi] / src / qhistory.py
1 #!/usr/bin/env python
2
3 """
4 http://www.grigoriev.ru/svgmath/ (MathML->SVG in Python)
5 http://helm.cs.unibo.it/mml-widget/ (MathML widget in C++)
6 """
7
8 import logging
9
10 from PyQt4 import QtGui
11 from PyQt4 import QtCore
12
13 import maeqt
14 import util.misc as misc_utils
15 import history
16 import operation
17
18
19 _moduleLogger = logging.getLogger(__name__)
20
21
22 class QCalcHistory(history.AbstractHistory):
23
24         _CLOSE_COLUMN = 0
25         _EQ_COLUMN = 1
26         _RESULT_COLUMN = 2
27
28         def __init__(self, errorReporter):
29                 super(QCalcHistory, self).__init__()
30                 self._prettyRenderer = operation.render_number()
31                 self._errorReporter = errorReporter
32
33                 self._historyStore = QtGui.QStandardItemModel()
34                 self._historyStore.setHorizontalHeaderLabels(["", "Equation", "Result"])
35                 self._historyStore.itemChanged.connect(self._on_item_changed)
36
37                 self._historyView = QtGui.QTreeView()
38                 self._historyView.setModel(self._historyStore)
39                 self._historyView.setUniformRowHeights(True)
40                 self._historyView.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
41                 self._historyView.setSelectionBehavior(QtGui.QAbstractItemView.SelectRows)
42                 self._historyView.setSelectionMode(QtGui.QAbstractItemView.SingleSelection)
43                 self._historyView.setHeaderHidden(True)
44                 self._historyView.activated.connect(self._on_row_activated)
45
46                 viewHeader = self._historyView.header()
47                 viewHeader.setSortIndicatorShown(True)
48                 viewHeader.setClickable(True)
49
50                 viewHeader.setResizeMode(self._CLOSE_COLUMN, QtGui.QHeaderView.ResizeToContents)
51                 viewHeader.setResizeMode(self._EQ_COLUMN, QtGui.QHeaderView.Stretch)
52                 viewHeader.setResizeMode(self._RESULT_COLUMN, QtGui.QHeaderView.ResizeToContents)
53                 viewHeader.setStretchLastSection(False)
54
55                 self._rowCount = 0
56                 self._programmaticUpdate = False
57                 self._closeIcon = maeqt.get_theme_icon(("window-close", "general_close", "gtk-close"))
58
59         @property
60         def toplevel(self):
61                 return self._historyView
62
63         @property
64         def errorReporter(self):
65                 return self._errorReporter
66
67         def push(self, node):
68                 simpleNode = node.simplify()
69
70                 closeIcon = self._closeIcon
71                 icon = QtGui.QStandardItem(closeIcon, "")
72                 icon.setEditable(False)
73                 icon.setCheckable(False)
74                 equation = QtGui.QStandardItem(operation.render_operation(self._prettyRenderer, node))
75                 equation.setData(node)
76                 equation.setCheckable(False)
77                 eqFont = equation.font()
78                 eqFont.setPointSize(max(eqFont.pointSize() - 3, 5))
79                 equation.setFont(eqFont)
80
81                 result = QtGui.QStandardItem(operation.render_operation(self._prettyRenderer, simpleNode))
82                 result.setData(simpleNode)
83                 result.setEditable(False)
84                 result.setCheckable(False)
85
86                 row = (icon, equation, result)
87                 self._historyStore.appendRow(row)
88
89                 index = result.index()
90                 self._historyView.scrollTo(index)
91                 self._rowCount += 1
92
93         def pop(self):
94                 if len(self) == 0:
95                         raise IndexError("Not enough items in the history for the operation")
96
97                 icon, equation, result = self._historyStore.takeRow(self._rowCount - 1)
98                 self._rowCount -= 1
99                 return equation.data().toPyObject()
100
101         def peek(self):
102                 if len(self) == 0:
103                         raise IndexError("Not enough items in the history for the operation")
104
105                 icon, equation, result = self._historyStore.takeRow(self._rowCount - 1)
106                 row = (icon, equation, result)
107                 self._historyStore.appendRow(row)
108
109                 return equation.data().toPyObject()
110
111         def clear(self):
112                 self._historyStore.clear()
113                 self._rowCount = 0
114
115         @misc_utils.log_exception(_moduleLogger)
116         def _on_row_activated(self, index):
117                 if index.column() == self._CLOSE_COLUMN:
118                         self._historyStore.removeRow(index.row(), index.parent())
119                         self._rowCount -= 1
120                 elif index.column() == self._EQ_COLUMN:
121                         self._duplicate_row(index)
122                 elif index.column() == self._RESULT_COLUMN:
123                         self._duplicate_row(index)
124                 else:
125                         raise NotImplementedError("Unsupported column to activate %s" % index.column())
126
127         @misc_utils.log_exception(_moduleLogger)
128         def _on_item_changed(self, item):
129                 if self._programmaticUpdate:
130                         _moduleLogger.info("Blocking updating %r recursively" % item)
131                         return
132                 self._programmaticUpdate = True
133                 try:
134                         if item.column() in [self._EQ_COLUMN, self._RESULT_COLUMN]:
135                                 self._update_input(item)
136                         else:
137                                 raise NotImplementedError("Unsupported column to edit %s" % item.column())
138                 except StandardError, e:
139                         self.errorReporter.push_exception()
140                 finally:
141                         self._programmaticUpdate = False
142
143         def _duplicate_row(self, index):
144                 item = self._historyStore.item(index.row(), self._EQ_COLUMN)
145                 self.push(item.data().toPyObject())
146
147         def _parse_value(self, value):
148                 raise NotImplementedError("What?")
149
150         def _update_input(self, item):
151                 node = item.data().toPyObject()
152                 try:
153                         eqNode = self._parse_value(str(item.text()))
154                         newText = operation.render_operation(self._prettyRenderer, eqNode)
155
156                         eqItem = self._historyStore.item(item.row(), self._EQ_COLUMN)
157                         eqItem.setData(eqNode)
158                         eqItem.setText(newText)
159
160                         resultNode = eqNode.simplify()
161                         resultText = operation.render_operation(self._prettyRenderer, resultNode)
162                         resultItem = self._historyStore.item(item.row(), self._RESULT_COLUMN)
163                         resultItem.setData(resultNode)
164                         resultItem.setText(resultText)
165                 except:
166                         oldText = operation.render_operation(self._prettyRenderer, node)
167                         item.setText(oldText)
168                         raise
169
170         def __len__(self):
171                 return self._rowCount
172
173         def __iter__(self):
174                 for i in xrange(self._rowCount):
175                         item = self._historyStore.item(i, self._EQ_COLUMN)
176                         if item is None:
177                                 continue
178                         yield item.data().toPyObject()