File: parameters.py

package info (click to toggle)
qgis 2.14.11%2Bdfsg-3%2Bdeb9u1
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 991,448 kB
  • ctags: 73,105
  • sloc: cpp: 535,362; python: 162,580; xml: 16,494; ansic: 8,031; sh: 1,788; perl: 1,559; sql: 727; yacc: 319; lex: 269; makefile: 251
file content (903 lines) | stat: -rw-r--r-- 29,745 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903

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

"""
***************************************************************************
    Parameters.py
    ---------------------
    Date                 : August 2012
    Copyright            : (C) 2012 by Victor Olaya
    Email                : volayaf at gmail dot com
***************************************************************************
*                                                                         *
*   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.                                   *
*                                                                         *
***************************************************************************
"""

__author__ = 'Victor Olaya'
__date__ = 'August 2012'
__copyright__ = '(C) 2012, Victor Olaya'

# This will get replaced with a git SHA1 when you do a git archive

__revision__ = '$Format:%H$'

import sys
import os
import re

from processing.tools.vector import resolveFieldIndex, features
from PyQt4.QtCore import QCoreApplication
from qgis.core import QgsRasterLayer, QgsVectorLayer
from processing.tools.system import isWindows
from processing.tools import dataobjects


def getParameterFromString(s):
    tokens = s.split("|")
    params = [t if unicode(t) != unicode(None) else None for t in tokens[1:]]
    clazz = getattr(sys.modules[__name__], tokens[0])
    return clazz(*params)


def parseBool(s):
    if s is None or s == unicode(None).lower():
        return None
    return unicode(s).lower() == unicode(True).lower()


class Parameter:

    """
    Base class for all parameters that a geoalgorithm might
    take as input.
    """

    def __init__(self, name='', description='', default=None, optional=False):
        self.name = name
        self.description = description
        self.default = default
        self.value = default

        self.isAdvanced = False

        # A hidden parameter can be used to set a hard-coded value.
        # It can be used as any other parameter, but it will not be
        # shown to the user
        self.hidden = False

        self.optional = parseBool(optional)

    def setValue(self, obj):
        """
        Sets the value of the parameter.

        Returns true if the value passed is correct for the type
        of parameter.
        """
        if obj is None:
            if not self.optional:
                return False
            self.value = None
            return True

        self.value = unicode(obj)
        return True

    def setDefaultValue(self):
        """
        Sets the value of the parameter to the default one

        Returns true if the default value is correct for the type
        of parameter.
        """
        return self.setValue(self.default)

    def __str__(self):
        return u'{} <{}>'.format(self.name, self.__class__.__name__)

    def getValueAsCommandLineParameter(self):
        """
        Returns the value of this parameter as it should have been
        entered in the console if calling an algorithm using the
        Processing.runalg() method.
        """
        return unicode(self.value)

    def typeName(self):
        return self.__class__.__name__.replace('Parameter', '').lower()

    def todict(self):
        return self.__dict__

    def tr(self, string, context=''):
        if context == '':
            context = 'Parameter'
        return QCoreApplication.translate(context, string)


class ParameterBoolean(Parameter):

    def __init__(self, name='', description='', default=None, optional=False):
        Parameter.__init__(self, name, description, parseBool(default), optional)

    def setValue(self, value):
        if value is None:
            if not self.optional:
                return False
            self.value = None
            return True

        if isinstance(value, basestring):
            self.value = unicode(value).lower() == unicode(True).lower()
        else:
            self.value = bool(value)
        return True

    def getAsScriptCode(self):
        return '##' + self.name + '=boolean ' + str(self.default)


class ParameterCrs(Parameter):

    def __init__(self, name='', description='', default=None, optional=False):
        '''The value is a string that uniquely identifies the
        coordinate reference system. Typically it is the auth id of the CRS
        (if the authority is EPSG) or proj4 string of the CRS (in case
        of other authorities or user defined projections).'''
        Parameter.__init__(self, name, description, default, optional)

    def setValue(self, value):
        if value is None or value.strip() == '':
            if not self.optional:
                return False
            self.value = None if value is None else value.strip()
            return True

        # TODO: check it is a valid authid
        self.value = unicode(value)
        return True

    def getValueAsCommandLineParameter(self):
        return '"' + unicode(self.value) + '"'

    def getAsScriptCode(self):
        return '##' + self.name + '=crs ' + str(self.default)


class ParameterDataObject(Parameter):

    def getValueAsCommandLineParameter(self):
        if self.value is None:
            return unicode(None)
        else:
            s = dataobjects.normalizeLayerSource(unicode(self.value))
            s = '"%s"' % s
            return s


class ParameterExtent(Parameter):

    USE_MIN_COVERING_EXTENT = 'USE_MIN_COVERING_EXTENT'

    def __init__(self, name='', description='', default=None, optional=False):
        Parameter.__init__(self, name, description, default, optional)
        # The value is a string in the form "xmin, xmax, ymin, ymax"

    def setValue(self, text):
        if text is None:
            if not self.optional:
                return False
            self.value = None
            return True

        tokens = unicode(text).split(',')
        if len(tokens) != 4:
            return False
        try:
            float(tokens[0])
            float(tokens[1])
            float(tokens[2])
            float(tokens[3])
            self.value = text
            return True
        except:
            return False

    def getValueAsCommandLineParameter(self):
        return '"' + unicode(self.value) + '"'

    def getAsScriptCode(self):
        return '##' + self.name + '=extent'


class ParameterFile(Parameter):

    def __init__(self, name='', description='', isFolder=False, optional=True, ext=None):
        Parameter.__init__(self, name, description, None, parseBool(optional))
        self.ext = ext
        self.isFolder = parseBool(isFolder)

    def getValueAsCommandLineParameter(self):
        return '"' + unicode(self.value) + '"'

    def setValue(self, obj):
        if obj is None or obj.strip() == '':
            if not self.optional:
                return False
            self.value = None if obj is None else obj.strip()
            return True

        if self.ext is not None and obj != '' and not obj.endswith(self.ext):
            return False
        self.value = unicode(obj)
        return True

    def typeName(self):
        if self.isFolder:
            return 'directory'
        else:
            return 'file'

    def getAsScriptCode(self):
        if self.isFolder:
            return '##' + self.name + '=folder'
        else:
            return '##' + self.name + '=file'


class ParameterFixedTable(Parameter):

    def __init__(self, name='', description='', numRows=3,
                 cols=['value'], fixedNumOfRows=False, optional=False):
        Parameter.__init__(self, name, description, None, optional)
        self.cols = cols
        if isinstance(cols, basestring):
            self.cols = self.cols.split(";")
        self.numRows = int(numRows)
        self.fixedNumOfRows = parseBool(fixedNumOfRows)

    def setValue(self, obj):
        if obj is None:
            if not self.optional:
                return False
            self.value = None
            return True

        # TODO: check that it contains a correct number of elements
        if isinstance(obj, (str, unicode)):
            self.value = obj
        else:
            self.value = ParameterFixedTable.tableToString(obj)
        return True

    def getValueAsCommandLineParameter(self):
        return '"' + unicode(self.value) + '"'

    @staticmethod
    def tableToString(table):
        tablestring = ''
        for i in range(len(table)):
            for j in range(len(table[0])):
                tablestring = tablestring + table[i][j] + ','
        tablestring = tablestring[:-1]
        return tablestring


class ParameterMultipleInput(ParameterDataObject):

    """A parameter representing several data objects.

    Its value is a string with substrings separated by semicolons,
    each of which represents the data source location of each element.
    """

    exported = None

    TYPE_VECTOR_ANY = -1
    TYPE_VECTOR_POINT = 0
    TYPE_VECTOR_LINE = 1
    TYPE_VECTOR_POLYGON = 2
    TYPE_RASTER = 3
    TYPE_FILE = 4

    def __init__(self, name='', description='', datatype=-1, optional=False):
        ParameterDataObject.__init__(self, name, description, None, optional)
        self.datatype = int(float(datatype))
        self.exported = None

    def setValue(self, obj):
        self.exported = None
        if obj is None:
            if not self.optional:
                return False
            self.value = None
            return True

        if isinstance(obj, list):
            if len(obj) == 0:
                if self.optional:
                    return True
                else:
                    return False
            self.value = ";".join([self.getAsString(lay) for lay in obj])
            return True
        else:
            self.value = unicode(obj)
            return True

    def getSafeExportedLayers(self):
        """Returns not the value entered by the user, but a string with
        semicolon-separated filenames which contains the data of the
        selected layers, but saved in a standard format (currently
        shapefiles for vector layers and GeoTiff for raster) so that
        they can be opened by most external applications.

        If there is a selection and QGIS is configured to use just the
        selection, it exports the layer even if it is already in a
        suitable format.

        Works only if the layer represented by the parameter value is
        currently loaded in QGIS. Otherwise, it will not perform any
        export and return the current value string.

        If the current value represents a layer in a suitable format,
        it does no export at all and returns that value.

        Currently, it works just for vector layer. In the case of
        raster layers, it returns the parameter value.

        The layers are exported just the first time the method is
        called. The method can be called several times and it will
        always return the same string, performing the export only the
        first time.
        """

        if self.exported:
            return self.exported
        self.exported = self.value
        layers = self.value.split(';')
        if layers is None or len(layers) == 0:
            return self.value
        if self.datatype == ParameterMultipleInput.TYPE_RASTER:
            for layerfile in layers:
                layer = dataobjects.getObjectFromUri(layerfile, False)
                if layer:
                    filename = dataobjects.exportRasterLayer(layer)
                    self.exported = self.exported.replace(layerfile, filename)
            return self.exported
        elif self.datatype == ParameterMultipleInput.TYPE_FILE:
            return self.value
        else:
            for layerfile in layers:
                layer = dataobjects.getObjectFromUri(layerfile, False)
                if layer:
                    filename = dataobjects.exportVectorLayer(layer)
                    self.exported = self.exported.replace(layerfile, filename)
            return self.exported

    def getAsString(self, value):
        if self.datatype == ParameterMultipleInput.TYPE_RASTER:
            if isinstance(value, QgsRasterLayer):
                return unicode(value.dataProvider().dataSourceUri())
            else:
                s = unicode(value)
                layers = dataobjects.getRasterLayers()
                for layer in layers:
                    if layer.name() == s:
                        return unicode(layer.dataProvider().dataSourceUri())
                return s
        if self.datatype == ParameterMultipleInput.TYPE_FILE:
            return unicode(value)
        else:
            if isinstance(value, QgsVectorLayer):
                return unicode(value.source())
            else:
                s = unicode(value)
                layers = dataobjects.getVectorLayers([self.datatype])
                for layer in layers:
                    if layer.name() == s:
                        return unicode(layer.source())
                return s

    def getFileFilter(self):
        if self.datatype == ParameterMultipleInput.TYPE_RASTER:
            exts = dataobjects.getSupportedOutputRasterLayerExtensions()
        elif self.datatype == ParameterMultipleInput.TYPE_FILE:
            return self.tr('All files (*.*)', 'ParameterMultipleInput')
        else:
            exts = dataobjects.getSupportedOutputVectorLayerExtensions()
        for i in range(len(exts)):
            exts[i] = self.tr('%s files(*.%s)', 'ParameterMultipleInput') % (exts[i].upper(), exts[i].lower())
        return ';;'.join(exts)

    def dataType(self):
        if self.datatype == self.TYPE_VECTOR_POINT:
            return 'points'
        elif self.datatype == self.TYPE_VECTOR_LINE:
            return 'lines'
        elif self.datatype == self.TYPE_VECTOR_POLYGON:
            return 'polygons'
        elif self.datatype == self.TYPE_RASTER:
            return 'rasters'
        elif self.datatype == self.TYPE_FILE:
            return 'files'
        else:
            return 'any vectors'

    def getAsScriptCode(self):
        if self.datatype == self.TYPE_RASTER:
            return '##' + self.name + '=multiple raster'
        if self.datatype == self.TYPE_FILE:
            return '##' + self.name + '=multiple file'
        else:
            return '##' + self.name + '=multiple vector'


class ParameterNumber(Parameter):

    def __init__(self, name='', description='', minValue=None, maxValue=None,
                 default=None, optional=False):
        Parameter.__init__(self, name, description, default, optional)

        if default is not None:
            try:
                self.default = int(unicode(default))
                self.isInteger = True
            except ValueError:
                self.default = float(default)
                self.isInteger = False
        else:
            self.isInteger = False

        if minValue is not None:
            self.min = int(float(minValue)) if self.isInteger else float(minValue)
        else:
            self.min = None
        if maxValue is not None:
            self.max = int(float(maxValue)) if self.isInteger else float(maxValue)
        else:
            self.max = None
        self.value = self.default

    def setValue(self, n):
        if n is None:
            if not self.optional:
                return False
            self.value = None
            return True

        try:
            if float(n) - int(float(n)) == 0:
                value = int(float(n))
            else:
                value = float(n)
            if self.min is not None:
                if value < self.min:
                    return False
            if self.max is not None:
                if value > self.max:
                    return False
            self.value = value
            return True
        except:
            return False

    def getAsScriptCode(self):
        return '##' + self.name + '=number ' + str(self.default)


class ParameterRange(Parameter):

    def __init__(self, name='', description='', default=None, optional=False):
        Parameter.__init__(self, name, description, default, optional)

        if default is not None:
            values = default.split(',')
            try:
                int(values[0])
                int(values[1])
                self.isInteger = True
            except:
                self.isInteger = False
        else:
            self.isInteger = False

    def setValue(self, text):
        if text is None:
            if not self.optional:
                return False
            self.value = None
            return True

        tokens = text.split(',')
        if len(tokens) != 2:
            return False
        try:
            float(tokens[0])
            float(tokens[1])
            self.value = text
            return True
        except:
            return False

    def getValueAsCommandLineParameter(self):
        return '"' + unicode(self.value) + '"' if self.value is not None else unicode(None)


class ParameterRaster(ParameterDataObject):

    def __init__(self, name='', description='', optional=False, showSublayersDialog=True):
        ParameterDataObject.__init__(self, name, description, None, optional)
        self.showSublayersDialog = parseBool(showSublayersDialog)
        self.exported = None

    def getSafeExportedLayer(self):
        """Returns not the value entered by the user, but a string with
        a filename which contains the data of this layer, but saved in
        a standard format (currently always a geotiff file) so that it
        can be opened by most external applications.

        Works only if the layer represented by the parameter value is
        currently loaded in QGIS. Otherwise, it will not perform any
        export and return the current value string.

        If the current value represents a layer in a suitable format,
        it does not export at all and returns that value.

        The layer is exported just the first time the method is called.
        The method can be called several times and it will always
        return the same file, performing the export only the first
        time.
        """

        if self.exported:
            return self.exported
        layer = dataobjects.getObjectFromUri(self.value, False)
        if layer:
            self.exported = dataobjects.exportRasterLayer(layer)
        else:
            self.exported = self.value
        return self.exported

    def setValue(self, obj):
        self.exported = None
        if obj is None:
            if not self.optional:
                return False
            self.value = None
            return True

        if isinstance(obj, QgsRasterLayer):
            self.value = unicode(obj.dataProvider().dataSourceUri())
            return True
        else:
            self.value = unicode(obj)
            return True

    def getFileFilter(self):
        exts = dataobjects.getSupportedOutputRasterLayerExtensions()
        for i in range(len(exts)):
            exts[i] = self.tr('%s files(*.%s)', 'ParameterRaster') % (exts[i].upper(), exts[i].lower())
        return ';;'.join(exts)

    def getAsScriptCode(self):
        return '##' + self.name + '=raster'


class ParameterSelection(Parameter):

    def __init__(self, name='', description='', options=[], default=None, isSource=False,
                 optional=False):
        Parameter.__init__(self, name, description, default, optional)
        isSource = parseBool(isSource)
        self.options = options
        if isSource:
            self.options = []
            layer = QgsVectorLayer(options[0], "layer", "ogr")
            if layer.isValid():
                try:
                    index = resolveFieldIndex(layer, options[1])
                    feats = features(layer)
                    for feature in feats:
                        self.options.append(unicode(feature.attributes()[index]))
                except ValueError:
                    pass
        elif isinstance(self.options, basestring):
            self.options = self.options.split(";")

        if default is not None:
            try:
                self.default = int(default)
            except:
                self.default = 0
            self.value = self.default

    def setValue(self, n):
        if n is None:
            if not self.optional:
                return False
            self.value = 0
            return True

        try:
            n = int(n)
            self.value = n
            return True
        except:
            return False


class ParameterString(Parameter):

    NEWLINE = '\n'
    ESCAPED_NEWLINE = '\\n'

    def __init__(self, name='', description='', default=None, multiline=False,
                 optional=False):
        Parameter.__init__(self, name, description, default, optional)
        self.multiline = parseBool(multiline)

    def setValue(self, obj):
        if obj is None:
            if not self.optional:
                return False
            self.value = None
            return True

        self.value = unicode(obj).replace(
            ParameterString.ESCAPED_NEWLINE,
            ParameterString.NEWLINE
        )
        return True

    def getValueAsCommandLineParameter(self):
        return ('"' + unicode(self.value.replace(ParameterString.NEWLINE,
                                                 ParameterString.ESCAPED_NEWLINE)) + '"'
                if self.value is not None else unicode(None))

    def getAsScriptCode(self):
        return '##' + self.name + '=string ' + self.default


class ParameterTable(ParameterDataObject):

    def __init__(self, name='', description='', optional=False):
        ParameterDataObject.__init__(self, name, description, None, optional)
        self.exported = None

    def setValue(self, obj):
        self.exported = None
        if obj is None:
            if not self.optional:
                return False
            self.value = None
            return True

        if isinstance(obj, QgsVectorLayer):
            source = unicode(obj.source())
            self.value = source
            return True
        else:
            self.value = unicode(obj)
            layers = dataobjects.getTables()
            for layer in layers:
                if layer.name() == self.value or layer.source() == self.value:
                    source = unicode(layer.source())
                    self.value = source
                    return True
            val = unicode(obj)
            self.value = val
            return os.path.exists(self.value)

    def getSafeExportedTable(self):
        """Returns not the value entered by the user, but a string with
        a filename which contains the data of this table, but saved in
        a standard format (currently always a DBF file) so that it can
        be opened by most external applications.

        Works only if the table represented by the parameter value is
        currently loaded in QGIS. Otherwise, it will not perform any
        export and return the current value string.

        If the current value represents a table in a suitable format,
        it does not export at all and returns that value.

        The table is exported just the first time the method is called.
        The method can be called several times and it will always
        return the same file, performing the export only the first
        time.
        """

        if self.exported:
            return self.exported
        table = dataobjects.getObjectFromUri(self.value, False)
        if table:
            self.exported = dataobjects.exportTable(table)
        else:
            self.exported = self.value
        return self.exported

    def getFileFilter(self):
        exts = ['csv', 'dbf']
        for i in range(len(exts)):
            exts[i] = self.tr('%s files(*.%s)', 'ParameterTable') % (exts[i].upper(), exts[i].lower())
        return ';;'.join(exts)

    def getAsScriptCode(self):
        return '##' + self.name + '=table'


class ParameterTableField(Parameter):

    DATA_TYPE_NUMBER = 0
    DATA_TYPE_STRING = 1
    DATA_TYPE_ANY = -1

    def __init__(self, name='', description='', parent=None, datatype=-1,
                 optional=False):
        Parameter.__init__(self, name, description, None, optional)
        self.parent = parent
        self.datatype = int(datatype)

    def getValueAsCommandLineParameter(self):
        return '"' + unicode(self.value) + '"' if self.value is not None else unicode(None)

    def setValue(self, value):
        if value is None:
            if not self.optional:
                return False
            self.value = None
            return True

        elif len(value) == 0 and not self.optional:
            return False
        self.value = unicode(value)
        return True

    def __str__(self):
        return self.name + ' <' + self.__module__.split('.')[-1] + ' from ' \
            + self.parent + '>'

    def dataType(self):
        if self.datatype == self.DATA_TYPE_NUMBER:
            return 'numeric'
        elif self.datatype == self.DATA_TYPE_STRING:
            return 'string'
        else:
            return 'any'

    def getAsScriptCode(self):
        return '##' + self.name + '=field ' + self.parent


class ParameterVector(ParameterDataObject):

    VECTOR_TYPE_POINT = 0
    VECTOR_TYPE_LINE = 1
    VECTOR_TYPE_POLYGON = 2
    VECTOR_TYPE_ANY = -1

    def __init__(self, name='', description='', shapetype=[-1],
                 optional=False):
        ParameterDataObject.__init__(self, name, description, None, optional)
        if isinstance(shapetype, int):
            shapetype = [shapetype]
        elif isinstance(shapetype, basestring):
            shapetype = [int(t) for t in shapetype.split(',')]
        self.shapetype = shapetype
        self.exported = None

    def setValue(self, obj):
        self.exported = None
        if obj is None:
            if not self.optional:
                return False
            self.value = None
            return True

        if isinstance(obj, QgsVectorLayer):
            self.value = unicode(obj.source())
            return True
        else:
            self.value = unicode(obj)
            return True

    def getSafeExportedLayer(self):
        """Returns not the value entered by the user, but a string with
        a filename which contains the data of this layer, but saved in
        a standard format (currently always a shapefile) so that it can
        be opened by most external applications.

        If there is a selection and QGIS is configured to use just the
        selection, if exports the layer even if it is already in a
        suitable format.

        Works only if the layer represented by the parameter value is
        currently loaded in QGIS. Otherwise, it will not perform any
        export and return the current value string.

        If the current value represents a layer in a suitable format,
        it does not export at all and returns that value.

        The layer is exported just the first time the method is called.
        The method can be called several times and it will always
        return the same file, performing the export only the first
        time.
        """

        if self.exported:
            return self.exported
        layer = dataobjects.getObjectFromUri(self.value, False)
        if layer:
            self.exported = dataobjects.exportVectorLayer(layer)
        else:
            self.exported = self.value
        return self.exported

    def getFileFilter(self):
        exts = dataobjects.getSupportedOutputVectorLayerExtensions()
        for i in range(len(exts)):
            exts[i] = self.tr('%s files(*.%s)', 'ParameterVector') % (exts[i].upper(), exts[i].lower())
        return ';;'.join(exts)

    def dataType(self):
        types = ''
        for shp in self.shapetype:
            if shp == self.VECTOR_TYPE_POINT:
                types += 'point, '
            elif shp == self.VECTOR_TYPE_LINE:
                types += 'line, '
            elif shp == self.VECTOR_TYPE_POLYGON:
                types += 'polygon, '
            else:
                types += 'any, '

        return types[:-2]

    def getAsScriptCode(self):
        return '##' + self.name + '=vector'


class ParameterGeometryPredicate(Parameter):

    predicates = ('intersects',
                  'contains',
                  'disjoint',
                  'equals',
                  'touches',
                  'overlaps',
                  'within',
                  'crosses')

    def __init__(self, name='', description='', left=None, right=None,
                 optional=False, enabledPredicates=None):
        Parameter.__init__(self, name, description, None, optional)
        self.left = left
        self.right = right
        self.value = None
        self.enabledPredicates = enabledPredicates
        if self.enabledPredicates is None:
            self.enabledPredicates = self.predicates

    def getValueAsCommandLineParameter(self):
        return unicode(self.value)

    def setValue(self, value):
        if value is None:
            if not self.optional:
                return False
            self.value = None
            return True
        elif len(value) == 0 and not self.optional:
            return False

        if isinstance(value, unicode):
            self.value = value.split(';') # relates to ModelerAlgorithm.resolveValue
        else:
            self.value = value
        return True