1# Copyright 2021 The Pigweed Authors 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); you may not 4# use this file except in compliance with the License. You may obtain a copy of 5# the License at 6# 7# https://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 11# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 12# License for the specific language governing permissions and limitations under 13# the License. 14"""Example text input-output Plugin.""" 15 16from typing import TYPE_CHECKING 17 18from prompt_toolkit.document import Document 19from prompt_toolkit.key_binding import KeyBindings, KeyPressEvent 20from prompt_toolkit.layout import Window 21from prompt_toolkit.widgets import SearchToolbar, TextArea 22 23from pw_console.widgets import ToolbarButton, WindowPane, WindowPaneToolbar 24 25if TYPE_CHECKING: 26 from pw_console.console_app import ConsoleApp 27 28 29class CalcPane(WindowPane): 30 """Example plugin that accepts text input and displays output. 31 32 This plugin is similar to the full-screen calculator example provided in 33 prompt_toolkit: 34 https://github.com/prompt-toolkit/python-prompt-toolkit/blob/3.0.23/examples/full-screen/calculator.py 35 36 It's a full window that can be moved around the user interface like other 37 Pigweed Console window panes. An input prompt is displayed on the bottom of 38 the window where the user can type in some math equation. When the enter key 39 is pressed the input is processed and the result shown in the top half of 40 the window. 41 42 Both input and output fields are prompt_toolkit TextArea objects which can 43 have their own options like syntax highlighting. 44 """ 45 def __init__(self): 46 # Call WindowPane.__init__ and set the title to 'Calculator' 47 super().__init__(pane_title='Calculator') 48 49 # Create a TextArea for the output-field 50 # TextArea is a prompt_toolkit widget that can display editable text in 51 # a buffer. See the prompt_toolkit docs for all possible options: 52 # https://python-prompt-toolkit.readthedocs.io/en/latest/pages/reference.html#prompt_toolkit.widgets.TextArea 53 self.output_field = TextArea( 54 # Optional Styles to apply to this TextArea 55 style='class:output-field', 56 # Initial text to put into the buffer. 57 text='Calculator Output', 58 # Allow this buffer to be in focus. This lets you drag select text 59 # contained inside, and edit the contents unless readonly. 60 focusable=True, 61 # Focus on mouse click. 62 focus_on_click=True, 63 ) 64 65 # This is the search toolbar and only appears if the user presses ctrl-r 66 # to do reverse history search (similar to bash or zsh). Its used by the 67 # input_field below. 68 self.search_field = SearchToolbar() 69 70 # Create a TextArea for the user input. 71 self.input_field = TextArea( 72 # The height is set to 1 line 73 height=1, 74 # Prompt string that appears before the cursor. 75 prompt='>>> ', 76 # Optional Styles to apply to this TextArea 77 style='class:input-field', 78 # We only allow one line input for this example but multiline is 79 # supported by prompt_toolkit. 80 multiline=False, 81 wrap_lines=False, 82 # Allow reverse history search 83 search_field=self.search_field, 84 # Allow this input to be focused. 85 focusable=True, 86 # Focus on mouse click. 87 focus_on_click=True, 88 ) 89 90 # The TextArea accept_handler function is called by prompt_toolkit (the 91 # UI) when the user presses enter. Here we override it to our own accept 92 # handler defined in this CalcPane class. 93 self.input_field.accept_handler = self.accept_input 94 95 # Create a toolbar for display at the bottom of this window. It will 96 # show the window title and toolbar buttons. 97 self.bottom_toolbar = WindowPaneToolbar(self) 98 self.bottom_toolbar.add_button( 99 ToolbarButton( 100 key='Enter', # Key binding for this function 101 description='Run Calculation', # Button name 102 # Function to run when clicked. 103 mouse_handler=self.run_calculation, 104 )) 105 self.bottom_toolbar.add_button( 106 ToolbarButton( 107 key='Ctrl-c', # Key binding for this function 108 description='Copy Output', # Button name 109 # Function to run when clicked. 110 mouse_handler=self.copy_all_output, 111 )) 112 113 # self.container is the root container that contains objects to be 114 # rendered in the UI, one on top of the other. 115 self.container = self._create_pane_container( 116 # Show the output_field on top 117 self.output_field, 118 # Draw a separator line with height=1 119 Window(height=1, char='─', style='class:line'), 120 # Show the input field just below that. 121 self.input_field, 122 # If ctrl-r reverse history is active, show the search box below the 123 # input_field. 124 self.search_field, 125 # Lastly, show the toolbar. 126 self.bottom_toolbar, 127 ) 128 129 def pw_console_init(self, app: 'ConsoleApp') -> None: 130 """Set the Pigweed Console application instance. 131 132 This function is called after the Pigweed Console starts up and allows 133 access to the user preferences. Prefs is required for creating new 134 user-remappable keybinds.""" 135 self.application = app 136 self.set_custom_keybinds() 137 138 def set_custom_keybinds(self) -> None: 139 # Fetch ConsoleApp preferences to load user keybindings 140 prefs = self.application.prefs 141 # Register a named keybind function that is user re-mappable 142 prefs.register_named_key_function( 143 'calc-pane.copy-selected-text', 144 # default bindings 145 ['c-c']) 146 147 # For setting additional keybindings to the output_field. 148 key_bindings = KeyBindings() 149 150 # Map the 'calc-pane.copy-selected-text' function keybind to the 151 # _copy_all_output function below. This will set 152 @prefs.register_keybinding('calc-pane.copy-selected-text', 153 key_bindings) 154 def _copy_all_output(_event: KeyPressEvent) -> None: 155 """Copy selected text from the output buffer.""" 156 self.copy_selected_output() 157 158 # Set the output_field controls key_bindings to the new bindings. 159 self.output_field.control.key_bindings = key_bindings 160 161 def run_calculation(self): 162 """Trigger the input_field's accept_handler. 163 164 This has the same effect as pressing enter in the input_field. 165 """ 166 self.input_field.buffer.validate_and_handle() 167 168 def accept_input(self, _buffer): 169 """Function run when the user presses enter in the input_field. 170 171 Takes a buffer argument that contains the user's input text. 172 """ 173 # Evaluate the user's calculator expression as Python and format the 174 # output result. 175 try: 176 output = "\n\nIn: {}\nOut: {}".format( 177 self.input_field.text, 178 # NOTE: Don't use 'eval' in real code (this is just an example) 179 eval(self.input_field.text)) # pylint: disable=eval-used 180 except BaseException as exception: # pylint: disable=broad-except 181 output = "\n\n{}".format(exception) 182 183 # Append the new output result to the existing output_field contents. 184 new_text = self.output_field.text + output 185 186 # Update the output_field with the new contents and move the 187 # cursor_position to the end. 188 self.output_field.buffer.document = Document( 189 text=new_text, cursor_position=len(new_text)) 190 191 def copy_selected_output(self): 192 """Copy highlighted text in the output_field to the system clipboard.""" 193 clipboard_data = self.output_field.buffer.copy_selection() 194 self.application.application.clipboard.set_data(clipboard_data) 195 196 def copy_all_output(self): 197 """Copy all text in the output_field to the system clipboard.""" 198 self.application.application.clipboard.set_text( 199 self.output_field.buffer.text) 200