QGIS/python/plugins/processing/modeler/CalculatorModelerParametersDialog.py

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

"""
***************************************************************************
    CalculatorModelerParametersDialog.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__ = '$Format:%H$'

from PyQt4.QtCore import *
from PyQt4.QtGui import *
from PyQt4 import QtCore, QtGui
from processing.parameters.ParameterNumber import ParameterNumber
from processing.modeler.ModelerAlgorithm import AlgorithmAndParameter
from processing.outputs.OutputNumber import OutputNumber


class CalculatorModelerParametersDialog(QtGui.QDialog):

    def __init__(self, alg, model, algIndex):
        QtGui.QDialog.__init__(self)
        self.setModal(True)
        self.alg = alg
        self.model = model
        self.algIndex = algIndex
        self.setupUi()
        self.params = None

    def setupUi(self):
        self.valueItems = {}
        self.dependentItems = {}
        self.resize(650, 450)
        self.buttonBox = QtGui.QDialogButtonBox()
        self.buttonBox.setOrientation(QtCore.Qt.Horizontal)
        self.buttonBox.setStandardButtons(QtGui.QDialogButtonBox.Cancel
                | QtGui.QDialogButtonBox.Ok)
        self.infoText = QtGui.QTextEdit()
        numbers = self.getNumbers()
        text = 'You can refer to model values in you formula, using \
                single-letter variables, as follows:'
        ichar = 97
        for number in numbers:
            text += chr(ichar) + '->' + number.name() + '\n'
            ichar += 1
        self.infoText.setText(text)
        self.infoText.setEnabled(False)
        self.formulaText = QtGui.QLineEdit()
        if hasattr(self.formulaText, 'setPlaceholderText'):
            self.formulaText.setPlaceholderText('[Enter your formula here]')
        self.setWindowTitle(self.alg.name)
        self.verticalLayout = QtGui.QVBoxLayout()
        self.verticalLayout.setSpacing(2)
        self.verticalLayout.setMargin(0)
        self.verticalLayout.addWidget(self.infoText)
        self.verticalLayout.addWidget(self.formulaText)
        self.verticalLayout.addWidget(self.buttonBox)
        self.setLayout(self.verticalLayout)
        QtCore.QObject.connect(self.buttonBox, QtCore.SIGNAL('accepted()'),
                               self.okPressed)
        QtCore.QObject.connect(self.buttonBox, QtCore.SIGNAL('rejected()'),
                               self.cancelPressed)
        QtCore.QMetaObject.connectSlotsByName(self)

    def getNumbers(self):
        numbers = []
        params = self.model.parameters
        for param in params:
            if isinstance(param, ParameterNumber):
                numbers.append(AlgorithmAndParameter(
                        AlgorithmAndParameter.PARENT_MODEL_ALGORITHM,
                        param.name, '', param.description))

        if self.algIndex is None:
            dependent = []
        else:
            dependent = self.model.getDependentAlgorithms(self.algIndex)
            dependent.append(self.algIndex)

        i = 0
        for alg in self.model.algs:
            if i not in dependent:
                for out in alg.outputs:
                    if isinstance(out, OutputNumber):
                        numbers.append(AlgorithmAndParameter(i, out.name,
                                       alg.name, out.description))
            i += 1
        return numbers

    def setParamValues(self):
        self.params = {}
        self.values = {}
        self.outputs = {}

        name = self.getSafeNameForHarcodedParameter(
                self.alg.getParameterFromName(self.alg.FORMULA))
        value = AlgorithmAndParameter(
                AlgorithmAndParameter.PARENT_MODEL_ALGORITHM, name)
        self.params[self.alg.FORMULA] = value
        formula = str(self.formulaText.text())
        self.values[name] = formula

        numbers = self.getNumbers()
        used = []
        for i in range(len(numbers)):
            if str(chr(i + 97)) in formula:
                used.append(numbers[i])
        i = 0
        for variable in used:
            paramname = self.alg.NUMBER + str(i)
            self.params[paramname] = variable
            i += 1

        # We create a dummy harcoded value for all unused variable slots
        paramname = self.alg.NUMBER + str(i)
        name = self.getSafeNameForHarcodedParameter(
                self.alg.getParameterFromName(paramname))
        value = AlgorithmAndParameter(
                AlgorithmAndParameter.PARENT_MODEL_ALGORITHM, name)
        self.values[name] = 0
        for i in range(len(used), self.alg.AVAILABLE_VARIABLES):
            paramname = self.alg.NUMBER + str(i)
            self.params[paramname] = value

        self.outputs[self.alg.RESULT] = None
        self.dependencies = []
        return True

    def getSafeNameForHarcodedParameter(self, param):
        if self.algIndex is not None:
            return 'HARDCODEDPARAMVALUE_' + param.name + '_' \
                + str(self.algIndex)
        else:
            return 'HARDCODEDPARAMVALUE_' + param.name + '_' \
                + str(len(self.model.algs))

    def okPressed(self):
        if self.setParamValues():
            self.close()
        else:
            QMessageBox.critical(self, 'Unable to add algorithm',
                                 'Wrong or missing parameter values')
            self.params = None

    def cancelPressed(self):
        self.params = None
        self.close()