# -*- coding: utf-8 -*-
#
# Copyright © 2009-2010 CEA
# Pierre Raybaut
# Licensed under the terms of the CECILL License
# (see guidata/__init__.py for details)

"""
dataset.dataitems
=================

The ``guidata.dataset.dataitems`` module contains implementation for 
concrete DataItems.
"""

from __future__ import division, unicode_literals

import os
import re
import datetime
import collections

from guidata.dataset.datatypes import DataItem, ItemProperty
from guidata.utils import utf8_to_unicode, add_extension
from guidata.config import _
from guidata.py3compat import to_text_string, is_text_string, TEXT_TYPES


[docs]class NumericTypeItem(DataItem):
    """
    Numeric data item
    """
    type = None
    def __init__(self, label, default=None, min=None, max=None,
                 nonzero=None, unit='', help=''):
        DataItem.__init__(self, label, default=default, help=help)
        self.set_prop("data", min=min, max=max, nonzero=nonzero)
        self.set_prop("display", unit=unit)
        
[docs]    def get_auto_help(self, instance):
        """Override DataItem method"""
        auto_help = {int: _('integer'), float: _('float')}[self.type]
        _min = self.get_prop_value("data", instance, "min")
        _max = self.get_prop_value("data", instance, "max")
        nonzero = self.get_prop_value("data", instance, "nonzero")
        unit = self.get_prop_value("display", instance, "unit")
        if _min is not None and _max is not None:
            auto_help += _(" between ")+str(_min)+ _(" and ")+str(_max)
        elif _min is not None:
            auto_help += _(" higher than ")+str(_min)
        elif _max is not None:
            auto_help += _(" lower than ")+str(_max)
        if nonzero:
            auto_help += ", "+_("non zero")
        if unit:
            auto_help += (", %s %s" % (_("unit:"), unit))
        return auto_help
        
[docs]    def format_string(self, instance, value, fmt, func):
        """Override DataItem method"""
        text = fmt % (func(value), )
        # We add directly the unit to 'text' (instead of adding it 
        # to 'fmt') to avoid string formatting error if '%' is in unit
        unit = self.get_prop_value("display", instance, "unit", '')
        if unit:
            text += ' '+unit
        return text

[docs]    def check_value(self, value):
        """Override DataItem method"""
        if not isinstance(value, self.type):
            return False
        if self.get_prop("data", "nonzero") and value == 0:
            return False
        _min = self.get_prop("data", "min")
        if _min is not None:
            if value < _min:
                return False
        _max = self.get_prop("data", "max")
        if _max is not None:
            if value > _max:
                return False
        return True

[docs]    def from_string(self, value):
        """Override DataItem method"""
        value = to_text_string(value) # necessary if value is a QString
        # String may contains numerical operands:
        if re.match(r'^([\d\(\)\+/\-\*.]|e)+$', value):
            try:
                return self.type(eval(value))
            except:
                pass
        return None


[docs]class FloatItem(NumericTypeItem):
    """
    Construct a float data item
        * label [string]: name
        * default [float]: default value (optional)
        * min [float]: minimum value (optional)
        * max [float]: maximum value (optional)
        * slider [bool]: if True, shows a slider widget right after the line 
          edit widget (default is False)
        * step [float]: step between tick values with a slider widget (optional)
        * nonzero [bool]: if True, zero is not a valid value (optional)
        * unit [string]: physical unit (optional)
        * help [string]: text shown in tooltip (optional)
    """
    type = float
    def __init__(self, label, default=None, min=None, max=None,
                 nonzero=None, unit='', step=0.1, slider=False, help=''):
        super(FloatItem, self).__init__(label, default=default, min=min,
                                max=max, nonzero=nonzero, unit=unit, help=help)
        self.set_prop("display", slider=slider)
        self.set_prop("data", step=step)

[docs]    def get_value_from_reader(self, reader):
        """Reads value from the reader object, inside the try...except 
        statement defined in the base item `deserialize` method"""
        return reader.read_float()


[docs]class IntItem(NumericTypeItem):
    """
    Construct an integer data item
        * label [string]: name
        * default [int]: default value (optional)
        * min [int]: minimum value (optional)
        * max [int]: maximum value (optional)
        * nonzero [bool]: if True, zero is not a valid value (optional)
        * unit [string]: physical unit (optional)
        * even [bool]: if True, even values are valid, if False,
          odd values are valid if None (default), ignored (optional)
        * slider [bool]: if True, shows a slider widget right after the line 
          edit widget (default is False)
        * help [string]: text shown in tooltip (optional)
    """
    type = int
    def __init__(self, label, default=None, min=None, max=None,
                 nonzero=None, unit='', even=None, slider=False, help=''):
        super(IntItem, self).__init__(label, default=default, min=min, max=max,
                                      nonzero=nonzero, unit=unit, help=help)
        self.set_prop("data", even=even)
        self.set_prop("display", slider=slider)
        
[docs]    def get_auto_help(self, instance):
        """Override DataItem method"""
        auto_help = super(IntItem, self).get_auto_help(instance)
        even = self.get_prop_value("data", instance, "even")
        if even is not None:
            if even:
                auto_help += ", "+_("even")
            else:
                auto_help += ", "+_("odd")
        return auto_help
        
[docs]    def check_value(self, value):
        """Override DataItem method"""
        valid = super(IntItem, self).check_value(value)
        if not valid:
            return False
        even = self.get_prop("data", "even")
        if even is not None:
            is_even = value//2 == value/2.
            if (even and not is_even) or (not even and is_even):
                return False
        return True

[docs]    def get_value_from_reader(self, reader):
        """Reads value from the reader object, inside the try...except 
        statement defined in the base item `deserialize` method"""
        return reader.read_int()


[docs]class StringItem(DataItem):
    """
    Construct a string data item
        * label [string]: name
        * default [string]: default value (optional)
        * help [string]: text shown in tooltip (optional)
        * notempty [bool]: if True, empty string is not a valid value (opt.)
        * wordwrap [bool]: toggle word wrapping (optional)
    """
    type = TEXT_TYPES
    def __init__(self, label, default=None, notempty=None,
                 wordwrap=False, help=''):
        DataItem.__init__(self, label, default=default, help=help)
        self.set_prop("data", notempty=notempty)
        self.set_prop("display", wordwrap=wordwrap)

[docs]    def check_value(self, value):
        """Override DataItem method"""
        notempty = self.get_prop("data", "notempty")
        if notempty and not value:
            return False
        return True
    
[docs]    def from_string(self, value):
        """Override DataItem method"""
        # QString -> str
        return to_text_string(value)

[docs]    def get_value_from_reader(self, reader):
        """Reads value from the reader object, inside the try...except 
        statement defined in the base item `deserialize` method"""
        return reader.read_unicode()


[docs]class TextItem(StringItem):
    """
    Construct a text data item (multiline string)
        * label [string]: name
        * default [string]: default value (optional)
        * help [string]: text shown in tooltip (optional)
        * notempty [bool]: if True, empty string is not a valid value (opt.)
        * wordwrap [bool]: toggle word wrapping (optional)
    """
    def __init__(self, label, default=None, notempty=None,
                 wordwrap=True, help=''):
        StringItem.__init__(self, label, default=default, notempty=notempty,
                            wordwrap=wordwrap, help=help)


[docs]class BoolItem(DataItem):
    """
    Construct a boolean data item
        * text [string]: form's field name (optional)
        * label [string]: name
        * default [string]: default value (optional)
        * help [string]: text shown in tooltip (optional)
    """
    type = bool
    def __init__(self, text='', label='', default=None, help=''):
        DataItem.__init__(self, label, default=default, help=help)
        self.set_prop("display", text=text)

[docs]    def get_value_from_reader(self, reader):
        """Reads value from the reader object, inside the try...except 
        statement defined in the base item `deserialize` method"""
        return reader.read_bool()


[docs]class DateItem(DataItem):
    """
    Construct a date data item.
        * text [string]: form's field name (optional)
        * label [string]: name
        * default [datetime.date]: default value (optional)
        * help [string]: text shown in tooltip (optional)
    """
    type = datetime.date

class DateTimeItem(DateItem):
    pass


[docs]class ColorItem(StringItem):
    """
    Construct a color data item
        * label [string]: name
        * default [string]: default value (optional)
        * help [string]: text shown in tooltip (optional)
    
    Color values are encoded as hexadecimal strings or Qt color names
    """
[docs]    def check_value(self, value):
        """Override DataItem method"""
        if not isinstance(value, self.type):
            return False
        from guidata.qthelpers import text_to_qcolor
        return text_to_qcolor(value).isValid()

[docs]    def get_value_from_reader(self, reader):
        """Reads value from the reader object, inside the try...except 
        statement defined in the base item `deserialize` method"""
        # Using read_str converts `numpy.string_` to `str` -- otherwise,
        # when passing the string to a QColor Qt object, any numpy.string_ will
        # be interpreted as no color (black)
        return reader.read_str()


[docs]class FileSaveItem(StringItem):
    """
    Construct a path data item for a file to be saved
        * label [string]: name
        * formats [string (or string list)]: wildcard filter
        * default [string]: default value (optional)
        * basedir [string]: default base directory (optional)
        * help [string]: text shown in tooltip (optional)
    """
    def __init__(self, label, formats='*', default=None,
                 basedir=None, all_files_first=False, help=''):
        DataItem.__init__(self, label, default=default, help=help)
        if isinstance(formats, str):
            formats = [formats]
        self.set_prop("data", formats=formats)
        self.set_prop("data", basedir=basedir)
        self.set_prop("data", all_files_first=all_files_first)

[docs]    def get_auto_help(self, instance):
        """Override DataItem method"""
        formats = self.get_prop("data", "formats")
        return _("all file types") if formats == ['*'] \
               else _("supported file types:") + " *.%s" % ", *.".join(formats)
    
[docs]    def check_value(self, value):
        """Override DataItem method"""
        if not isinstance(value, self.type):
            return False
        return len(value)>0

[docs]    def from_string(self, value):
        """Override DataItem method"""
        return add_extension(self, value)


[docs]class FileOpenItem(FileSaveItem):
    """
    Construct a path data item for a file to be opened
        * label [string]: name
        * formats [string (or string list)]: wildcard filter
        * default [string]: default value (optional)
        * basedir [string]: default base directory (optional)
        * help [string]: text shown in tooltip (optional)
    """
[docs]    def check_value(self, value):
        """Override DataItem method"""
        if not isinstance(value, self.type):
            return False
        return os.path.exists(value) and os.path.isfile(value)


[docs]class FilesOpenItem(FileSaveItem):
    """
    Construct a path data item for multiple files to be opened.
        * label [string]: name
        * formats [string (or string list)]: wildcard filter
        * default [string]: default value (optional)
        * basedir [string]: default base directory (optional)
        * help [string]: text shown in tooltip (optional)
    """
    type = list
    def __init__(self, label, formats='*', default=None,
                 basedir=None, all_files_first=False, help=''):
        if is_text_string(default):
            default = [default]
        FileSaveItem.__init__(self, label, formats=formats,
                              default=default, basedir=basedir,
                              all_files_first=all_files_first, help=help)

[docs]    def check_value(self, value):
        """Override DataItem method"""
        allexist = True
        for path in value:
            allexist = allexist and os.path.exists(path) \
                       and os.path.isfile(path)
        return allexist

[docs]    def from_string(self, value):        
        """Override DataItem method"""
        value = to_text_string(value)
        if value.endswith("']"):
            value = eval(value)
        else:
            value = [value]
        return [add_extension(self, path) for path in value]

[docs]    def serialize(self, instance, writer):
        """Serialize this item"""
        value = self.get_value(instance)
        writer.write_sequence([fname.encode("utf-8") for fname in value])

[docs]    def get_value_from_reader(self, reader):
        """Reads value from the reader object, inside the try...except 
        statement defined in the base item `deserialize` method"""
        return [to_text_string(fname, "utf-8")
                for fname in reader.read_sequence()]


[docs]class DirectoryItem(StringItem):
    """
    Construct a path data item for a directory.
        * label [string]: name
        * default [string]: default value (optional)
        * help [string]: text shown in tooltip (optional)
    """
[docs]    def check_value(self, value):
        """Override DataItem method"""
        if not isinstance(value, self.type):
            return False
        return os.path.exists(value) and os.path.isdir(value)


class FirstChoice(object):
    pass

[docs]class ChoiceItem(DataItem):
    """
    Construct a data item for a list of choices.
        * label [string]: name
        * choices [list, tuple or function]: string list or (key, label) list
          function of two arguments (item, value) returning a list of tuples 
          (key, label, image) where image is an icon path, a QIcon instance 
          or a function of one argument (key) returning a QIcon instance
        * default [-]: default label or default key (optional)
        * help [string]: text shown in tooltip (optional)
    """
    def __init__(self, label, choices, default=FirstChoice, help=''):
        if isinstance(choices, collections.Callable):
            _choices_data = ItemProperty(choices)
        else:
            _choices_data = []
            for idx, choice in enumerate(choices):
                _choices_data.append( self._normalize_choice(idx, choice) )
        if default is FirstChoice and\
           not isinstance(choices, collections.Callable):
            default = _choices_data[0][0]
        elif default is FirstChoice:
            default = None
        DataItem.__init__(self, label, default=default, help=help)
        self.set_prop("data", choices=_choices_data )

    def _normalize_choice(self, idx, choice_tuple):
        if isinstance(choice_tuple, tuple):
            key, value = choice_tuple
        else:
            key = idx
            value = choice_tuple

        if isinstance(value, str):
            value = utf8_to_unicode(value)
        return (key, value, None)
            
#    def _choices(self, item):
#        _choices_data = self.get_prop("data", "choices")
#        if callable(_choices_data):
#            return _choices_data(self, item)
#        return _choices_data

[docs]    def get_string_value(self, instance):
        """Override DataItem method"""
        value = self.get_value(instance)
        choices = self.get_prop_value("data", instance, "choices")
        #print "ShowChoiceWidget:", choices, value
        for choice in choices:
            if choice[0] == value:
                return to_text_string(choice[1])
        else:
            return DataItem.get_string_value(self, instance)
        
        
[docs]class MultipleChoiceItem(ChoiceItem):
    """
    Construct a data item for a list of choices -- multiple choices can be selected
        * label [string]: name
        * choices [list or tuple]: string list or (key, label) list
        * default [-]: default label or default key (optional)
        * help [string]: text shown in tooltip (optional)
    """
    def __init__(self, label, choices, default=(), help=''):
        ChoiceItem.__init__(self, label, choices, default, help)
        self.set_prop("display", shape = (1, -1))
        
[docs]    def horizontal(self, row_nb=1):
        """
        Method to arange choice list horizontally on `n` rows
        
        Example:
        nb = MultipleChoiceItem("Number", ['1', '2', '3'] ).horizontal(2)
        """
        self.set_prop("display", shape = (row_nb, -1))
        return self
    
[docs]    def vertical(self, col_nb=1):
        """
        Method to arange choice list vertically on `n` columns
        
        Example:
        nb = MultipleChoiceItem("Number", ['1', '2', '3'] ).vertical(2)
        """
        self.set_prop("display", shape = (-1, col_nb))
        return self

[docs]    def serialize(self, instance, writer):
        """Serialize this item"""
        value = self.get_value(instance)
        seq = []
        _choices = self.get_prop_value("data", instance, "choices")
        for key, _label, _img in _choices:
            seq.append( key in value )
        writer.write_sequence( seq )

[docs]    def deserialize(self, instance, reader):
        """Deserialize this item"""
        flags = reader.read_sequence()
        # We could have trouble with objects providing their own choice
        # function which depend on not yet deserialized values
        _choices = self.get_prop_value("data", instance, "choices")
        value = []
        for idx, flag in enumerate(flags):
            if flag:
                value.append( _choices[idx][0] )
        self.__set__(instance, value)


[docs]class ImageChoiceItem(ChoiceItem):
    """
    Construct a data item for a list of choices with images
        * label [string]: name
        * choices [list, tuple or function]: (label, image) list or 
          (key, label, image) list function of two arguments (item, value) 
          returning a list of tuples (key, label, image) where image is an 
          icon path, a QIcon instance or a function of one argument (key) 
          returning a QIcon instance
        * default [-]: default label or default key (optional)
        * help [string]: text shown in tooltip (optional)
    """
    def _normalize_choice(self, idx, choice_tuple):
        assert isinstance(choice_tuple, tuple)
        if len(choice_tuple) == 3:
            key, value, img = choice_tuple
        else:
            key = idx
            value, img = choice_tuple

        if isinstance(value, str):
            value = utf8_to_unicode(value)
        return (key, value, img)


[docs]class FloatArrayItem(DataItem):
    """
    Construct a float array data item
        * label [string]: name
        * default [numpy.ndarray]: default value (optional)
        * help [string]: text shown in tooltip (optional)
        * format [string]: formatting string (example: '%.3f') (optional)
        * transpose [bool]: transpose matrix (display only)
        * large [bool]: view all float of the array
        * minmax [string]: "all" (default), "columns", "rows"
    """
    def __init__(self, label, default=None, help='', format='%.3f',
                 transpose=False, minmax="all"):
        DataItem.__init__(self, label, default=default, help=help)
        self.set_prop("display", format=format, transpose=transpose,
                      minmax=minmax)
        
[docs]    def format_string(self, instance, value, fmt, func):
        """Override DataItem method"""
        larg = self.get_prop_value("display", instance, "large", False)
        fmt = self.get_prop_value("display", instance, "format", "%s")
        unit = self.get_prop_value("display", instance, "unit", "")
        v = func(value)        
        if larg:
            text = "= ["
            for flt in v[:-1]:
                text += fmt % flt + "; "
            text += fmt % v[-1] + "]"
        else:
            text = "~= " + fmt % v.mean()
            text += " [" + fmt % v.min()
            text += " .. " + fmt % v.max()
            text += "]"            
        text += " %s" % unit
        return to_text_string(text)

[docs]    def serialize(self, instance, writer):
        """Serialize this item"""
        value = self.get_value(instance)
        writer.write_array(value)

[docs]    def get_value_from_reader(self, reader):
        """Reads value from the reader object, inside the try...except 
        statement defined in the base item `deserialize` method"""
        return reader.read_array()


[docs]class ButtonItem(DataItem):
    """
    Construct a simple button that calls a method when hit
        * label [string]: text shown on the button
        * callback [function]: function with four parameters (dataset, item, value, parent)
            - dataset [DataSet]: instance of the parent dataset
            - item [DataItem]: instance of ButtonItem (i.e. self)
            - value [unspecified]: value of ButtonItem (default ButtonItem 
              value or last value returned by the callback)
            - parent [QObject]: button's parent widget
        * icon [QIcon or string]: icon show on the button (optional)
          (string: icon filename as in guidata/guiqwt image search paths)
        * default [unspecified]: default value passed to the callback (optional)
        * help [string]: text shown in button's tooltip (optional)
    
    The value of this item is unspecified but is passed to the callback along 
    with the whole dataset. The value is assigned the callback`s return value.
    """
    def __init__(self, label, callback, icon=None, default=None, help=''):
        DataItem.__init__(self, label, default=default, help=help)
        self.set_prop("display", callback=callback)
        self.set_prop("display", icon=icon)

    def serialize(self, instance, writer):
        pass
    
    def deserialize(self, instance, reader):
        pass
    


[docs]class DictItem(ButtonItem):
    """
    Construct a dictionary data item
        * label [string]: name
        * default [dict]: default value (optional)
        * help [string]: text shown in tooltip (optional)
    """
    def __init__(self, label, default=None, help=''):
        def dictedit(instance, item, value, parent):
            from spyderlib.widgets.dicteditor import DictEditor
            editor = DictEditor(parent)
            value_was_none = value is None
            if value_was_none:
                value = {}
            editor.setup(value)
            if editor.exec_():
                return editor.get_value()
            else:
                if value_was_none:
                    return
                return value
        ButtonItem.__init__(self, label, dictedit,
                            icon='dictedit.png', default=default, help=help)


[docs]class FontFamilyItem(StringItem):
    """
    Construct a font family name item
        * label [string]: name
        * default [string]: default value (optional)
        * help [string]: text shown in tooltip (optional)
    """
    pass