File size: 27,709 Bytes
2d876d1
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
"""Module contains the class to create a fuzzy prompt."""
import asyncio
import math
from typing import (
    TYPE_CHECKING,
    Any,
    Callable,
    Dict,
    List,
    Optional,
    Tuple,
    Union,
    cast,
)

from pfzy import fuzzy_match
from pfzy.score import fzy_scorer, substr_scorer
from pfzy.types import HAYSTACKS
from prompt_toolkit.application.application import Application
from prompt_toolkit.buffer import Buffer
from prompt_toolkit.filters.cli import IsDone
from prompt_toolkit.layout.containers import (
    ConditionalContainer,
    FloatContainer,
    HSplit,
    Window,
)
from prompt_toolkit.layout.controls import BufferControl, DummyControl
from prompt_toolkit.layout.dimension import Dimension, LayoutDimension
from prompt_toolkit.layout.layout import Layout
from prompt_toolkit.layout.processors import AfterInput, BeforeInput
from prompt_toolkit.lexers.base import SimpleLexer
from prompt_toolkit.validation import ValidationError
from prompt_toolkit.widgets.base import Frame

from InquirerPy.base import FakeDocument, InquirerPyUIListControl
from InquirerPy.base.list import BaseListPrompt
from InquirerPy.containers.instruction import InstructionWindow
from InquirerPy.containers.message import MessageWindow
from InquirerPy.containers.validation import ValidationFloat
from InquirerPy.enum import INQUIRERPY_POINTER_SEQUENCE
from InquirerPy.exceptions import InvalidArgument
from InquirerPy.separator import Separator
from InquirerPy.utils import (
    InquirerPyDefault,
    InquirerPyKeybindings,
    InquirerPyListChoices,
    InquirerPyMessage,
    InquirerPySessionResult,
    InquirerPyStyle,
    InquirerPyValidate,
    calculate_height,
)

if TYPE_CHECKING:
    from prompt_toolkit.key_binding.key_processor import KeyPressEvent

__all__ = ["FuzzyPrompt"]


class InquirerPyFuzzyControl(InquirerPyUIListControl):
    """An :class:`~prompt_toolkit.layout.UIControl` class that displays a list of choices.

    This only displays the chocies. The actual input buffer will be handled by a separate
    :class:`~prompt_toolkit.layout.BufferControl`.

    Reference the parameter definition in :class:`.FuzzyPrompt`.
    """

    def __init__(
        self,
        choices: InquirerPyListChoices,
        pointer: str,
        marker: str,
        current_text: Callable[[], str],
        max_lines: int,
        session_result: Optional[InquirerPySessionResult],
        multiselect: bool,
        marker_pl: str,
        match_exact: bool,
    ) -> None:
        self._pointer = pointer
        self._marker = marker
        self._marker_pl = marker_pl
        self._current_text = current_text
        self._max_lines = max_lines if max_lines > 0 else 1
        self._scorer = fzy_scorer if not match_exact else substr_scorer
        super().__init__(
            choices=choices,
            default=None,
            session_result=session_result,
            multiselect=multiselect,
        )

    def _format_choices(self) -> None:
        for index, choice in enumerate(self.choices):
            if isinstance(choice["value"], Separator):
                raise InvalidArgument(
                    "fuzzy prompt argument choices should not contain Separator"
                )
            choice["index"] = index
            choice["indices"] = []
        self._filtered_choices = self.choices
        self._first_line = 0
        self._last_line = min(self._max_lines, self.choice_count)
        self._height = self._last_line - self._first_line

    def _get_hover_text(self, choice) -> List[Tuple[str, str]]:
        """Get the current highlighted line of text.

        If in the middle of filtering, loop through the char and color
        indices matched char into style class `class:fuzzy_match`.

        Returns:
            FormattedText in list of tuple format.
        """
        display_choices = []
        display_choices.append(("class:pointer", self._pointer))
        display_choices.append(
            (
                "class:marker",
                self._marker
                if self.choices[choice["index"]]["enabled"]
                else self._marker_pl,
            )
        )
        display_choices.append(("[SetCursorPosition]", ""))
        if not choice["indices"]:
            display_choices.append(("class:pointer", choice["name"]))
        else:
            indices = set(choice["indices"])
            for index, char in enumerate(choice["name"]):
                if index in indices:
                    display_choices.append(("class:fuzzy_match", char))
                else:
                    display_choices.append(("class:pointer", char))
        return display_choices

    def _get_normal_text(self, choice) -> List[Tuple[str, str]]:
        """Get the line of text in `FormattedText`.

        If in the middle of filtering, loop through the char and color
        indices matched char into `class:fuzzy_match`.

        Calculate spaces of pointer to make the choice equally align.

        Returns:
            FormattedText in list of tuple format.
        """
        display_choices = []
        display_choices.append(("class:pointer", len(self._pointer) * " "))
        display_choices.append(
            (
                "class:marker",
                self._marker
                if self.choices[choice["index"]]["enabled"]
                else self._marker_pl,
            )
        )
        if not choice["indices"]:
            display_choices.append(("", choice["name"]))
        else:
            indices = set(choice["indices"])
            for index, char in enumerate(choice["name"]):
                if index in indices:
                    display_choices.append(("class:fuzzy_match", char))
                else:
                    display_choices.append(("", char))
        return display_choices

    def _get_formatted_choices(self) -> List[Tuple[str, str]]:
        """Get all available choices in formatted text format.

        Overriding this method because `self.choice` will be the
        full choice list. Using `self.filtered_choice` to get
        a list of choice based on current_text.

        Returns:
            FormattedText in list of tuple format.
        """
        display_choices = []
        if self.choice_count == 0:
            self._selected_choice_index = 0
            return display_choices

        if self._selected_choice_index < 0:
            self._selected_choice_index = 0
        elif self._selected_choice_index >= self.choice_count:
            self._selected_choice_index = self.choice_count - 1

        if (self._last_line - self._first_line) < min(self.choice_count, self._height):
            self._last_line = min(self.choice_count, self._height)
            self._first_line = self._last_line - min(self.choice_count, self._height)

        if self._selected_choice_index <= self._first_line:
            self._first_line = self._selected_choice_index
            self._last_line = self._first_line + min(self._height, self.choice_count)
        elif self._selected_choice_index >= self._last_line:
            self._last_line = self._selected_choice_index + 1
            self._first_line = self._last_line - min(self._height, self.choice_count)

        if self._last_line > self.choice_count:
            self._last_line = self.choice_count
            self._first_line = self._last_line - min(self._height, self.choice_count)
        if self._first_line < 0:
            self._first_line = 0
            self._last_line = self._first_line + min(self._height, self.choice_count)

        for index in range(self._first_line, self._last_line):
            if index == self.selected_choice_index:
                display_choices += self._get_hover_text(self._filtered_choices[index])
            else:
                display_choices += self._get_normal_text(self._filtered_choices[index])
            display_choices.append(("", "\n"))
        if display_choices:
            display_choices.pop()
        return display_choices

    async def _filter_choices(self, wait_time: float) -> List[Dict[str, Any]]:
        """Call to filter choices using fzy fuzzy match.

        Args:
            wait_time: Additional time to wait before filtering the choice.

        Returns:
            Filtered choices.
        """
        if not self._current_text():
            for choice in self.choices:
                choice["indices"] = []
            choices = self.choices
        else:
            await asyncio.sleep(wait_time)
            choices = await fuzzy_match(
                self._current_text(),
                cast(HAYSTACKS, self.choices),
                key="name",
                scorer=self._scorer,
            )
        return choices

    @property
    def selection(self) -> Dict[str, Any]:
        """Override this value since `self.choice` does not indicate the choice displayed.

        `self.filtered_choice` is the up to date choice displayed.

        Returns:
            A dictionary of name and value for the current pointed choice.
        """
        return self._filtered_choices[self.selected_choice_index]

    @property
    def choice_count(self) -> int:
        """int: Filtered choice count."""
        return len(self._filtered_choices)


class FuzzyPrompt(BaseListPrompt):
    """Create a prompt that lists choices while also allowing fuzzy search like fzf.

    A wrapper class around :class:`~prompt_toolkit.application.Application`.

    Fuzzy search using :func:`pfzy.match.fuzzy_match` function.

    Override the default keybindings for up/down as j/k cannot be bind even if `editing_mode` is vim
    due to the input buffer.

    Args:
        message: The question to ask the user.
            Refer to :ref:`pages/dynamic:message` documentation for more details.
        choices: List of choices to display and select.
            Refer to :ref:`pages/dynamic:choices` documentation for more details.
        style: An :class:`InquirerPyStyle` instance.
            Refer to :ref:`Style <pages/style:Alternate Syntax>` documentation for more details.
        vi_mode: Use vim keybinding for the prompt.
            Refer to :ref:`pages/kb:Keybindings` documentation for more details.
        default: Set the default value in the search buffer.
            Different than other list type prompts, the `default` parameter tries to replicate what fzf does and
            add the value in `default` to search buffer so it starts searching immediatelly.
            Refer to :ref:`pages/dynamic:default` documentation for more details.
        qmark: Question mark symbol. Custom symbol that will be displayed infront of the question before its answered.
        amark: Answer mark symbol. Custom symbol that will be displayed infront of the question after its answered.
        pointer: Pointer symbol. Customer symbol that will be used to indicate the current choice selection.
        instruction: Short instruction to display next to the question.
        long_instruction: Long instructions to display at the bottom of the prompt.
        validate: Add validation to user input.
            The main use case for this prompt would be when `multiselect` is True, you can enforce a min/max selection.
            Refer to :ref:`pages/validator:Validator` documentation for more details.
        invalid_message: Error message to display when user input is invalid.
            Refer to :ref:`pages/validator:Validator` documentation for more details.
        transformer: A function which performs additional transformation on the value that gets printed to the terminal.
            Different than `filter` parameter, this is only visual effect and won’t affect the actual value returned by :meth:`~InquirerPy.base.simple.BaseSimplePrompt.execute`.
            Refer to :ref:`pages/dynamic:transformer` documentation for more details.
        filter: A function which performs additional transformation on the result.
            This affects the actual value returned by :meth:`~InquirerPy.base.simple.BaseSimplePrompt.execute`.
            Refer to :ref:`pages/dynamic:filter` documentation for more details.
        height: Preferred height of the prompt.
            Refer to :ref:`pages/height:Height` documentation for more details.
        max_height: Max height of the prompt.
            Refer to :ref:`pages/height:Height` documentation for more details.
        multiselect: Enable multi-selection on choices.
            You can use `validate` parameter to control min/max selections.
            Setting to True will also change the result from a single value to a list of values.
        prompt: Input prompt symbol. Custom symbol to display infront of the input buffer to indicate for input.
        border: Create border around the choice window.
        info: Display choice information similar to fzf --info=inline next to the prompt.
        match_exact: Use exact sub-string match instead of using fzy fuzzy match algorithm.
        exact_symbol: Custom symbol to display in the info section when `info=True`.
        marker: Marker Symbol. Custom symbol to indicate if a choice is selected.
            This will take effects when `multiselect` is True.
        marker_pl: Marker place holder when the choice is not selected.
            This is empty space by default.
        keybindings: Customise the builtin keybindings.
            Refer to :ref:`pages/kb:Keybindings` for more details.
        cycle: Return to top item if hit bottom during navigation or vice versa.
        wrap_lines: Soft wrap question lines when question exceeds the terminal width.
        raise_keyboard_interrupt: Raise the :class:`KeyboardInterrupt` exception when `ctrl-c` is pressed. If false, the result
            will be `None` and the question is skiped.
        mandatory: Indicate if the prompt is mandatory. If True, then the question cannot be skipped.
        mandatory_message: Error message to show when user attempts to skip mandatory prompt.
        session_result: Used internally for :ref:`index:Classic Syntax (PyInquirer)`.

    Examples:
        >>> from InquirerPy import inquirer
        >>> result = inquirer.fuzzy(message="Select one:", choices=[1, 2, 3]).execute()
        >>> print(result)
        1
    """

    def __init__(
        self,
        message: InquirerPyMessage,
        choices: InquirerPyListChoices,
        default: InquirerPyDefault = "",
        pointer: str = INQUIRERPY_POINTER_SEQUENCE,
        style: Optional[InquirerPyStyle] = None,
        vi_mode: bool = False,
        qmark: str = "?",
        amark: str = "?",
        transformer: Optional[Callable[[Any], Any]] = None,
        filter: Optional[Callable[[Any], Any]] = None,
        instruction: str = "",
        long_instruction: str = "",
        multiselect: bool = False,
        prompt: str = INQUIRERPY_POINTER_SEQUENCE,
        marker: str = INQUIRERPY_POINTER_SEQUENCE,
        marker_pl: str = " ",
        border: bool = False,
        info: bool = True,
        match_exact: bool = False,
        exact_symbol: str = " E",
        height: Optional[Union[str, int]] = None,
        max_height: Optional[Union[str, int]] = None,
        validate: Optional[InquirerPyValidate] = None,
        invalid_message: str = "Invalid input",
        keybindings: Optional[InquirerPyKeybindings] = None,
        cycle: bool = True,
        wrap_lines: bool = True,
        raise_keyboard_interrupt: bool = True,
        mandatory: bool = True,
        mandatory_message: str = "Mandatory prompt",
        session_result: Optional[InquirerPySessionResult] = None,
    ) -> None:
        if not keybindings:
            keybindings = {}
        self._prompt = prompt
        self._info = info
        self._task = None
        self._rendered = False
        self._exact_symbol = exact_symbol

        keybindings = {
            "up": [{"key": "up"}, {"key": "c-p"}],
            "down": [{"key": "down"}, {"key": "c-n"}],
            "toggle": [],
            "toggle-exact": [],
            **keybindings,
        }
        super().__init__(
            message=message,
            style=style,
            border=border,
            vi_mode=vi_mode,
            qmark=qmark,
            amark=amark,
            transformer=transformer,
            filter=filter,
            validate=validate,
            invalid_message=invalid_message,
            multiselect=multiselect,
            instruction=instruction,
            long_instruction=long_instruction,
            keybindings=keybindings,
            cycle=cycle,
            wrap_lines=wrap_lines,
            raise_keyboard_interrupt=raise_keyboard_interrupt,
            mandatory=mandatory,
            mandatory_message=mandatory_message,
            session_result=session_result,
        )
        self.kb_func_lookup = {"toggle-exact": [{"func": self._toggle_exact}]}
        self._default = (
            default
            if not isinstance(default, Callable)
            else cast(Callable, default)(self._result)
        )
        self._height_offset += 1  # search input
        self._dimmension_height, self._dimmension_max_height = calculate_height(
            height, max_height, height_offset=self.height_offset
        )

        self._content_control: InquirerPyFuzzyControl = InquirerPyFuzzyControl(
            choices=choices,
            pointer=pointer,
            marker=marker,
            current_text=self._get_current_text,
            max_lines=self._dimmension_max_height,
            session_result=session_result,
            multiselect=multiselect,
            marker_pl=marker_pl,
            match_exact=match_exact,
        )

        self._buffer = Buffer(on_text_changed=self._on_text_changed)
        input_window = Window(
            height=LayoutDimension.exact(1),
            content=BufferControl(
                self._buffer,
                [
                    AfterInput(self._generate_after_input),
                    BeforeInput(self._generate_before_input),
                ],
                lexer=SimpleLexer("class:input"),
            ),
        )

        choice_height_dimmension = lambda: Dimension(
            max=self._dimmension_max_height,
            preferred=self._dimmension_height,
            min=self.content_control._height if self.content_control._height > 0 else 1,
        )
        self.choice_window = Window(
            content=self.content_control,
            height=choice_height_dimmension,
            dont_extend_height=True,
        )

        main_content_window = HSplit([input_window, self.choice_window])
        if self._border:
            main_content_window = Frame(main_content_window)
        self._layout = Layout(
            FloatContainer(
                content=HSplit(
                    [
                        MessageWindow(
                            message=self._get_prompt_message,
                            filter=True,
                            wrap_lines=self._wrap_lines,
                            show_cursor=True,
                        ),
                        ConditionalContainer(
                            main_content_window,
                            filter=~IsDone(),
                        ),
                        ConditionalContainer(
                            Window(content=DummyControl()),
                            filter=~IsDone() & self._is_displaying_long_instruction,
                        ),
                        InstructionWindow(
                            message=self._long_instruction,
                            filter=~IsDone() & self._is_displaying_long_instruction,
                            wrap_lines=self._wrap_lines,
                        ),
                    ],
                ),
                floats=[
                    ValidationFloat(
                        invalid_message=self._get_error_message,
                        filter=self._is_invalid & ~IsDone(),
                        wrap_lines=self._wrap_lines,
                        left=0,
                        bottom=self._validation_window_bottom_offset,
                    ),
                ],
            )
        )
        self._layout.focus(input_window)

        self._application = Application(
            layout=self._layout,
            style=self._style,
            key_bindings=self._kb,
            editing_mode=self._editing_mode,
            after_render=self._after_render,
        )

    def _toggle_exact(self, _, value: Optional[bool] = None) -> None:
        """Toggle matching algorithm.

        Switch between fzy fuzzy match or sub-string exact match.

        Args:
            value: Specify the value to toggle.
        """
        if value is not None:
            self.content_control._scorer = fzy_scorer if not value else substr_scorer
        else:
            self.content_control._scorer = (
                fzy_scorer
                if self.content_control._scorer == substr_scorer
                else substr_scorer
            )

    def _on_rendered(self, _) -> None:
        """Render callable choices and set the buffer default text.

        Setting buffer default text has to be after application is rendered and choice are loaded,
        because `self._filter_choices` will use the event loop from `Application`.
        """
        if self._default:
            default_text = str(self._default)
            self._buffer.text = default_text
            self._buffer.cursor_position = len(default_text)

    def _handle_toggle_all(self, _, value: Optional[bool] = None) -> None:
        """Toggle all choice `enabled` status.

        Args:
            value: Specify the value to toggle.
        """
        if not self._multiselect:
            return
        for choice in self.content_control._filtered_choices:
            raw_choice = self.content_control.choices[choice["index"]]
            if isinstance(raw_choice["value"], Separator):
                continue
            raw_choice["enabled"] = value if value else not raw_choice["enabled"]

    def _generate_after_input(self) -> List[Tuple[str, str]]:
        """Virtual text displayed after the user input."""
        display_message = []
        if self._info:
            display_message.append(("", "  "))
            display_message.append(
                (
                    "class:fuzzy_info",
                    f"{self.content_control.choice_count}/{len(self.content_control.choices)}",
                )
            )
            if self._multiselect:
                display_message.append(
                    ("class:fuzzy_info", f" ({len(self.selected_choices)})")
                )
            if self.content_control._scorer == substr_scorer:
                display_message.append(("class:fuzzy_info", self._exact_symbol))
        return display_message

    def _generate_before_input(self) -> List[Tuple[str, str]]:
        """Display prompt symbol as virtual text before user input."""
        display_message = []
        display_message.append(("class:fuzzy_prompt", "%s " % self._prompt))
        return display_message

    def _filter_callback(self, task):
        """Redraw `self._application` when the filter task is finished."""
        if task.cancelled():
            return
        self.content_control._filtered_choices = task.result()
        self._application.invalidate()

    def _calculate_wait_time(self) -> float:
        """Calculate wait time to smoother the application on big data set.

        Using digit of the choices lengeth to get wait time.
        For digit greater than 6, using formula 2^(digit - 5) * 0.3 to increase the wait_time.

        Returns:
            Desired wait time before running the filter.
        """
        wait_table = {
            2: 0.05,
            3: 0.1,
            4: 0.2,
            5: 0.3,
        }
        digit = 1
        if len(self.content_control.choices) > 0:
            digit = int(math.log10(len(self.content_control.choices))) + 1

        if digit < 2:
            return 0.0
        if digit in wait_table:
            return wait_table[digit]
        return wait_table[5] * (2 ** (digit - 5))

    def _on_text_changed(self, _) -> None:
        """Handle buffer text change event.

        1. Check if there is current task running.
        2. Cancel if already has task, increase wait_time
        3. Create a filtered_choice task in asyncio event loop
        4. Add callback

        1. Run a new filter on all choices.
        2. Re-calculate current selected_choice_index
            if it exceeds the total filtered_choice.
        3. Avoid selected_choice_index less than zero,
            this fix the issue of cursor lose when:
            choice -> empty choice -> choice

        Don't need to create or check asyncio event loop, `prompt_toolkit`
        application already has a event loop running.
        """
        if self._invalid:
            self._invalid = False
        wait_time = self._calculate_wait_time()
        if self._task and not self._task.done():
            self._task.cancel()
        self._task = asyncio.create_task(
            self.content_control._filter_choices(wait_time)
        )
        self._task.add_done_callback(self._filter_callback)

    def _handle_toggle_choice(self, _) -> None:
        """Handle tab event, alter the `selected` state of the choice."""
        if not self._multiselect:
            return
        current_selected_index = self.content_control.selection["index"]
        self.content_control.choices[current_selected_index][
            "enabled"
        ] = not self.content_control.choices[current_selected_index]["enabled"]

    def _handle_enter(self, event: "KeyPressEvent") -> None:
        """Handle enter event.

        Validate the result first.

        In multiselect scenario, if no TAB is entered, then capture the current
        highlighted choice and return the value in a list.
        Otherwise, return all TAB choices as a list.

        In normal scenario, reutrn the current highlighted choice.

        If current UI contains no choice due to filter, return None.
        """
        try:
            fake_document = FakeDocument(self.result_value)
            self._validator.validate(fake_document)  # type: ignore
            if self._multiselect:
                self.status["answered"] = True
                if not self.selected_choices:
                    self.status["result"] = [self.content_control.selection["name"]]
                    event.app.exit(result=[self.content_control.selection["value"]])
                else:
                    self.status["result"] = self.result_name
                    event.app.exit(result=self.result_value)
            else:
                self.status["answered"] = True
                self.status["result"] = self.content_control.selection["name"]
                event.app.exit(result=self.content_control.selection["value"])
        except ValidationError as e:
            self._set_error(str(e))
        except IndexError:
            self.status["answered"] = True
            self.status["result"] = None if not self._multiselect else []
            event.app.exit(result=None if not self._multiselect else [])

    @property
    def content_control(self) -> InquirerPyFuzzyControl:
        """InquirerPyFuzzyControl: Override for type-hinting."""
        return cast(InquirerPyFuzzyControl, super().content_control)

    @content_control.setter
    def content_control(self, value: InquirerPyFuzzyControl) -> None:
        self._content_control = value

    def _get_current_text(self) -> str:
        """Get current input buffer text."""
        return self._buffer.text