Utils.py

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

"""
/***************************************************************************
Name                 : Omero RT
Description          : Omero plugin
Date                 : August 15, 2010 
copyright            : (C) 2010 by Giuseppe Sucameli (Faunalia)
email                : sucameli@faunalia.it
 ***************************************************************************/

Omero plugin
Works done from Faunalia (http://www.faunalia.it) with funding from Regione 
Toscana - S.I.T.A. (http://www.regione.toscana.it/territorio/cartografia/index.html)

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
"""

from PyQt4.QtCore import *
from PyQt4.QtGui import *

from qgis.core import *
import qgis.gui


class MapTool(QObject):
	canvas = None
	registeredToolStatusMsg = {}

	def __init__(self, mapToolClass, canvas=None):
		QObject.__init__(self)
		if canvas == None:
			if MapTool.canvas == None:
				raise Exception( "MapTool.canvas is None" )
			else:
				self.canvas = MapTool.canvas
		else:
			self.canvas = canvas
			if MapTool.canvas == None:
				MapTool.canvas = canvas

		self.tool = mapToolClass( self.canvas )
		QObject.connect(self.tool, SIGNAL( "geometryDrawingEnded" ), self.onEnd)

	def deleteLater(self):
		self.unregisterStatusMsg()
		self.stopCapture()
		self.tool.deleteLater()
		del self.tool
		return QObject.deleteLater(self)


	def registerStatusMsg(self, statusMessage):
		MapTool.registeredToolStatusMsg[self] = statusMessage

	def unregisterStatusMsg(self):
		if not MapTool.registeredToolStatusMsg.has_key( self ):
			return
		del MapTool.registeredToolStatusMsg[self]


	def onEnd(self, geometry):
		self.stopCapture()
		if geometry == None:
			return
		self.emit( SIGNAL( "geometryEmitted" ), geometry )

	def isActive(self):
		return self.canvas != None and self.canvas.mapTool() == self.tool

	def startCapture(self):
		self.canvas.setMapTool( self.tool )

	def stopCapture(self):
		self.canvas.unsetMapTool( self.tool )

	class Drawer(qgis.gui.QgsMapToolEmitPoint):
		def __init__(self, canvas, isPolygon=False):
			self.canvas = canvas
			self.isPolygon = isPolygon
			qgis.gui.QgsMapToolEmitPoint.__init__(self, self.canvas)

			self.rubberBand = qgis.gui.QgsRubberBand( self.canvas, self.isPolygon )
			self.rubberBand.setColor( Qt.red )
			self.rubberBand.setBrushStyle(Qt.DiagCrossPattern)
			self.rubberBand.setWidth( 1 )

			self.snapper = qgis.gui.QgsMapCanvasSnapper( self.canvas )

			self.isEmittingPoints = False

		def __del__(self):
			del self.rubberBand
			del self.snapper
			self.deleteLater()

		def reset(self):
			self.isEmittingPoints = False
			self.rubberBand.reset( self.isPolygon )

		def canvasPressEvent(self, e):
			if e.button() == Qt.RightButton:
				self.isEmittingPoints = False
				self.emit( SIGNAL("geometryDrawingEnded"), self.geometry() )
				return

			if e.button() == Qt.LeftButton:
				self.isEmittingPoints = True
			else:
				return
			point = self.toMapCoordinates( e.pos() )
			self.rubberBand.addPoint( point, True )	# true to update canvas
			self.rubberBand.show()

		def canvasMoveEvent(self, e):
			if not self.isEmittingPoints:
				return

			retval, snapResults = self.snapper.snapToBackgroundLayers( e.pos() )
			if retval == 0 and len(snapResults) > 0:
				point = snapResults[0].snappedVertex
			else:
				point = self.toMapCoordinates( e.pos() )

			self.rubberBand.movePoint( point )

		def isValid(self):
			return self.rubberBand.numberOfVertices() > 0

		def geometry(self):
			if not self.isValid():
				return None
			geom = self.rubberBand.asGeometry()
			if geom == None:
				return
			return QgsGeometry.fromWkt( geom.exportToWkt() )

		def deactivate(self):
			qgis.gui.QgsMapTool.deactivate(self)
			self.reset()
			self.emit(SIGNAL("deactivated()"))


class FeatureFinder(MapTool):

	def __init__(self, canvas=None):
		MapTool.__init__(self, qgis.gui.QgsMapToolEmitPoint, canvas=canvas)
		QObject.connect(self.tool, SIGNAL( "canvasClicked(const QgsPoint &, Qt::MouseButton)" ), self.onEnd)

	def onEnd(self, point, button):
		self.stopCapture()
		self.emit( SIGNAL("pointEmitted"), point, button )

	@classmethod
	def findAtPoint(self, layer, point, onlyTheClosestOne=True, onlyIds=False, overrideSearchRadius=False):
		QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))

		point = MapTool.canvas.mapRenderer().mapToLayerCoordinates(layer, point)

		# recupera il valore del raggio di ricerca
		settings = QSettings()
		if QGis.QGIS_VERSION_INT < 10900 or (getattr(qgis.gui.QgsMapTool, "searchRadiusMM", None) is None):
			radius = settings.value( "/Map/identifyRadius", QGis.DEFAULT_IDENTIFY_RADIUS, type=float )
			if radius and radius <= 0:
				# XXX: in QGis 1.8 QGis.DEFAULT_IDENTIFY_RADIUS is 0, 
				# this cause the rectangle is empty and the select 
				# returns all the features...
				radius = 0.5	# it means 0.50% of the canvas extent
			radius = MapTool.canvas.extent().width() * radius/100
		
		elif overrideSearchRadius == True:
			radius = 0.5
			radius = MapTool.canvas.extent().width() * radius/100
					
		else:
			unit = layer.crs().mapUnits()
			if unit == QGis.Feet:
				radius = (qgis.gui.QgsMapTool.searchRadiusMM()/1000.0)*3.28084
			else:
				# meters or unknow
				radius = qgis.gui.QgsMapTool.searchRadiusMM()/1000.0

		# crea il rettangolo da usare per la ricerca
		rect = QgsRectangle()
		rect.setXMinimum(point.x() - radius)
		rect.setXMaximum(point.x() + radius)
		rect.setYMinimum(point.y() - radius)
		rect.setYMaximum(point.y() + radius)

		# recupera le feature che intersecano il rettangolo
		ret = None
		request = QgsFeatureRequest(rect)
		request.setFlags(QgsFeatureRequest.ExactIntersect)
		
		if onlyTheClosestOne:
			minDist = -1
			featureId = None
			rectClosest = QgsGeometry.fromRect(rect)

			for f in layer.getFeatures(request):
				if onlyTheClosestOne:
					geom = f.geometry()
					distance = geom.distance(rectClosest)
					if minDist < 0 or distance < minDist:
						minDist = distance
						featureId = f.id()

			if onlyIds:
				ret = featureId
			elif featureId != None:
				f = layer.getFeatures(QgsFeatureRequest().setFilterFid( featureId ))
				ret = f.next()

		else:
			IDs = [f.id() for f in layer.getFeatures(request)]

			if onlyIds:
				ret = IDs
			else:
				ret = []
				for featureId in IDs:
					f = layer.getFeatures(QgsFeatureRequest().setFilterFid( featureId ))
					ret.append( f )

		QApplication.restoreOverrideCursor()
		return ret
				

class PolygonDrawer(MapTool):

	class PolygonDrawer(MapTool.Drawer):
		def __init__(self, canvas):
			MapTool.Drawer.__init__(self, canvas, QGis.Polygon)

	def __init__(self, canvas=None):
		MapTool.__init__(self, self.PolygonDrawer, canvas)

class LineDrawer(MapTool):

	class LineDrawer(MapTool.Drawer):
		def __init__(self, canvas):
			MapTool.Drawer.__init__(self, canvas, QGis.Line)

	def __init__(self, canvas=None):
		MapTool.__init__(self, self.LineDrawer, canvas)


class PicViewer(QGraphicsView):
	def __init__(self, parent):
		QGraphicsView.__init__(self, parent)

	def loadImage(self, image):
		self.resetTransform()	# restore the original scale
		scene = self.scene()
		if scene == None:
			scene = PicViewer.Scene()
			self.connect( scene, SIGNAL( "openPicRequested" ), SIGNAL( "openPicRequested" ) )
			self.setScene( scene )

		scene.clear()

		from AutomagicallyUpdater import AutomagicallyUpdater
		value = AutomagicallyUpdater._getRealValue( image )
		if value == None:
			return

		item = PicViewer.Picture( value, self.size() )
		scene.addItem( item )

		#itemRect = item.boundingRect()
		#scale = min( self.width()/itemRect.width(), self.height()/itemRect.height() )
		#self.scale( scale, scale )
		#self.centerOn( item )


	def getBytes(self, itemIndex=0):
		if self.scene() == None:
			return
		items = self.scene().items()
		if len(items) <= 0 or itemIndex >= len(items):
			return
		return items[itemIndex].getBytes()

	def clearCache(self, itemIndex=0):
		if self.scene() == None:
			return
		items = self.scene().items()
		if len(items) <= 0:
			return
		items[itemIndex].clearCache()

	class Scene(QGraphicsScene):
		def __init__(self, *argv):
			QGraphicsScene.__init__(self, *argv)

		def mouseDoubleClickEvent(self, event):
			if event.button() != Qt.LeftButton:
				return
			self.emit( SIGNAL( "openPicRequested" ) )
			QGraphicsScene.mouseDoubleClickEvent(self, event)

	class Picture(QGraphicsPixmapItem):
		def __init__(self, image, newSize=QSize(), parent=None):
			self.clearCache()

			pixmap = QPixmap()
			if isinstance(image, str) or isinstance(image, unicode):
				try:
					infile = open( unicode(image).encode('utf8'), "rb" )
					self.imageBytes = QByteArray( infile.read() )
					infile.close()
					pixmap = QPixmap( image )
				except Exception as e:
					self.imageBytes = QByteArray.fromHex(QByteArray(image))
					pixmap.loadFromData( self.imageBytes )

			elif isinstance(image, QByteArray):
				self.imageBytes = image
				pixmap.loadFromData( self.imageBytes )

			if newSize.isValid():
				pixmap = pixmap.scaled( newSize.width(), newSize.height(), Qt.KeepAspectRatio )

			QGraphicsPixmapItem.__init__(self, pixmap, parent)

		def getBytes(self):
			return self.imageBytes

		def clearCache(self):
			self.imageBytes = None


class TemporaryFile:
	# gestisci i file temporanei, eliminandoli alla chiusura del plugin
	tmpFiles = {}

	KEY_SCHEDAEDIFICIO = 'SchedaEdificio'
	KEY_SCHEDAEDIFICIO2HTML = 'SchedaEdificio2Html'
	KEY_VISUALIZZAFOTO = 'DlgVisualizzaFoto'

	@staticmethod
	def getNewFile(key=None, ext=None):
		tmp = QTemporaryFile()
		if ext != None:
			tmp.setFileTemplate( "%s.%s" % ( tmp.fileTemplate(), ext ) )
		if not TemporaryFile.tmpFiles.has_key( key ):
			TemporaryFile.tmpFiles[ key ] = [ tmp ]
		else:
			TemporaryFile.tmpFiles[ key ].append( tmp )
		return tmp

	@staticmethod
	def delFile(tmp, key=None):

		def deleteTempFile(tmp, key):
			TemporaryFile.tmpFiles[ key ].remove( tmp )
			tmp.deleteLater()
			del tmp

		if not TemporaryFile.tmpFiles.has_key( key ):
			return False
		if tmp != None:	# rimuovi solo il file passato
			if TemporaryFile.tmpFiles[ key ].count( tmp ) > 0:
				deleteTempFile(tmp, key)
		else:	# rimuovi tutti i file che hanno quella chiave
			for tmp in TemporaryFile.tmpFiles[ key ]:
				deleteTempFile(tmp, key)
			del TemporaryFile.tmpFiles[ key ]
		return True

	@staticmethod
	def delAllFiles(key=None):
		return TemporaryFile.delFile(None, key)

	@staticmethod
	def clear():
		for key in TemporaryFile.tmpFiles.keys():
			TemporaryFile.delAllFiles(key)
		TemporaryFile.tmpFiles = {}


	@staticmethod
	def salvaDati(dati, tempKey=None, ext=None):
		if dati == None:
			return

		tmp = TemporaryFile.getNewFile( tempKey, ext )
		if not tmp.open():
			TemporaryFile.delFile( tmp, tempKey )
			return
		filename = tmp.fileName()
		tmp.close()

		outfile = open( filename.encode("utf-8"), "wb" )
		try:
			outfile.write( dati )
		finally:
			outfile.close()

		return filename


class Porting:
	
	@staticmethod
	def str(value):
		''' utility function to sobstitute QString method avoiding str(None) producing 'None' '''
		if value:
			return str(value)
		else:
			if isinstance(value, str):
				return ''
			else:
				return None