sysmon_pytk.style_manager

  1# SPDX-FileCopyrightText: © 2024 Stacey Adams <stacey.belle.rose@gmail.com>
  2# SPDX-License-Identifier: MIT
  3
  4"""
  5Tk Style Manager.
  6"""
  7
  8from __future__ import annotations
  9
 10import re
 11import tkinter as tk
 12from tkinter import font, ttk
 13from typing import TYPE_CHECKING, TypeVar
 14
 15import darkdetect
 16
 17import azure
 18
 19from . import font_utils
 20
 21if TYPE_CHECKING:
 22    from tkinter.font import Font
 23
 24    from .settings import Settings
 25
 26T = TypeVar("T")
 27
 28_DARK_CUTOFF_SQR = 127.5 * 127.5
 29_LEN_HEXCOLOR = len("#FFFFFF")
 30
 31
 32def is_dark(hexcolor: str) -> bool:
 33    """
 34    Determine whether a given hex color is light or dark.
 35
 36    Parameters
 37    ----------
 38    hexcolor: str
 39        a string with the format "#xxxxxx" where x is a hex digit (0-9, A-F)
 40
 41    Returns
 42    -------
 43    bool
 44        True when the color is determined to be dark; False otherwise.
 45
 46    Examples
 47    --------
 48    >>> is_dark("#000000")
 49    True
 50    >>> is_dark("#ffffff")
 51    False
 52    >>> is_dark("#123456")
 53    True
 54    >>> is_dark("#449F55")
 55    False
 56    """
 57    assert len(hexcolor) == _LEN_HEXCOLOR  # nosec B101
 58    assert hexcolor[:1] == "#"  # nosec B101
 59    if re.search(r"^#[\dA-Fa-f]{6}$", hexcolor) is None:
 60        msg = "hexcolor must start with '#' and have 6 hexadecimal digits"
 61        raise ValueError(msg)
 62    r = int(hexcolor[1:3], 16)
 63    g = int(hexcolor[3:5], 16)
 64    b = int(hexcolor[5:7], 16)
 65    # calculate the square of the luminance and compare it to a cutoff value of 127.5²
 66    # this way, sqrt() doesn't need to be called
 67    hsp = 0.299 * (r * r) + 0.587 * (g * g) + 0.114 * (b * b)
 68    return hsp < _DARK_CUTOFF_SQR
 69
 70
 71class StyleManager:
 72    """
 73    Tk Style Manager.
 74    """
 75
 76    @classmethod
 77    def get_dark_mode(cls, settings: Settings) -> bool:
 78        """
 79        Determine dark mode by checking settings or detecting the system theme.
 80        """
 81        if settings.theme == "Dark":
 82            return True
 83        if settings.theme == "Light":
 84            return False
 85        return darkdetect.isDark()
 86
 87    @classmethod
 88    def init_theme(cls, root: tk.Tk, settings: Settings) -> None:
 89        """
 90        Initialize theme and styles for the application.
 91        """
 92        azure.init_theme(root)  # pylint: disable=W0212
 93        cls.update_by_dark_mode(root, settings)
 94        cls.init_fonts(settings)
 95        root.option_add("*TCombobox*Listbox.font", "TkDefaultFont")
 96        root.option_add("*tearOff", False)  # Fix menus
 97        root.bind_class("Menu", "<<ThemeChanged>>", cls.update_menu)
 98
 99    @classmethod
100    def init_fonts(cls, settings: Settings) -> None:
101        """
102        Initialize the fonts to be used.
103
104        The following tk named fonts are updated based on Settings:
105
106        * TkDefaultFont - set to Regular Font from Settings
107        * TkTextFont - set to Regular Font from Settings
108        * TkMenuFont - set to Regular Font from Settings
109        * TkFixedFont - set to Fixed Font from Settings
110
111        In addition, widgets are configured to use TkDefaultFont.
112        """
113        base_font = font.nametofont("TkDefaultFont")
114        text_font = font.nametofont("TkTextFont")
115        menu_font = font.nametofont("TkMenuFont")
116        fixed_font = font.nametofont("TkFixedFont")
117        if settings.regular_font.name:
118            settings.regular_font.configure_font(base_font)
119            settings.regular_font.configure_font(text_font)
120            settings.regular_font.configure_font(menu_font)
121        else:
122            base_font.configure(family=font_utils.MAIN_FONT_FAMILY, size=12)
123            text_font.configure(family=font_utils.MAIN_FONT_FAMILY, size=12)
124            menu_font.configure(family=font_utils.MAIN_FONT_FAMILY, size=12)
125        if settings.fixed_font.name:
126            settings.fixed_font.configure_font(fixed_font)
127        else:
128            fixed_font.configure(family=font_utils.FIXED_FONT_FAMILY, size=12)
129        style = ttk.Style()
130        style.configure("TButton", font="TkDefaultFont")
131        style.configure("TRadiobutton", font="TkDefaultFont")
132        style.configure("TLabelFrame", font="TkDefaultFont")
133        style.configure("TNotebook", font="TkDefaultFont")
134        style.configure("TNotebook.Tab", font="TkDefaultFont")
135        style.configure("Switch.TCheckbutton", font="TkDefaultFont")
136        style.configure("System.TLabel", font="TkDefaultFont")
137        style.configure("URL.TLabel", foreground="#0066cc")
138
139    @classmethod
140    def update_by_dark_mode(cls, root: tk.Tk, settings: Settings) -> None:
141        """
142        Update styles based on dark mode.
143
144        Colors are updated for various styles and widgets:
145
146        * Safe.TLabel style (green)
147        * Warn.TLabel style (yellow)
148        * Alert.TLabel style (red)
149        * Combobox Listbox background (grey)
150        """
151        dark_mode = cls.get_dark_mode(settings)
152        azure.set_theme("dark" if dark_mode else "light", root)
153        root.event_generate("<<ThemeChanged>>")
154        style = ttk.Style()
155        if dark_mode:
156            style.configure("Safe.TLabel", foreground="#00aa00")
157            style.configure("Warn.TLabel", foreground="#ffff22")
158            style.configure("Alert.TLabel", foreground="#ff2222")
159            root.option_add("*TCombobox*Listbox.background", "#444444")
160        else:
161            style.configure("Safe.TLabel", foreground="#009900")
162            style.configure("Warn.TLabel", foreground="#aaaa00")
163            style.configure("Alert.TLabel", foreground="#cc0000")
164            root.option_add("*TCombobox*Listbox.background", "#dddddd")
165        # ComboboxPopdownFrame must be reset every time the theme changes
166        style.configure("ComboboxPopdownFrame", relief=tk.FLAT)
167
168    @classmethod
169    def test_dark_mode(cls, trueval: T, falseval: T) -> T:
170        """
171        If currently in dark mode, return `trueval`; otherwise return `falseval`.
172        """
173        style = ttk.Style()
174        background = style.lookup("TLabel", "background")
175        if is_dark(f"{background}"):
176            return trueval
177        return falseval
178
179    @classmethod
180    def update_menu(cls, event: tk.Event) -> None:
181        """
182        Update the foreground and background colors of a menu, based on dark mode.
183        """
184        if isinstance(event.widget, tk.Menu):
185            event.widget.configure(
186                background=cls.get_menu_background(),
187                foreground=cls.get_menu_foreground()
188            )
189
190    @classmethod
191    def get_menu_background(cls) -> str:
192        """
193        Get the background color for menus, based on dark mode.
194        """
195        return cls.test_dark_mode("#444444", "#dddddd")
196
197    @classmethod
198    def get_menu_foreground(cls) -> str:
199        """
200        Get the foreground color for menus, based on dark mode.
201        """
202        return cls.test_dark_mode("#ffffff", "#000000")
203
204    @classmethod
205    def get_base_font(cls) -> Font:
206        """
207        Get the base font for use in the application. Returns `TkDefaultFont`.
208        """
209        return font.nametofont("TkDefaultFont")
210
211    @classmethod
212    def get_large_font(cls) -> Font:
213        """
214        Get the large font for use in the application.
215
216        Returns a modified `TkDefaultFont` with font size increased by 4.
217        """
218        return font_utils.modify_named_font(
219            "TkDefaultFont", size=cls.get_base_font().actual()["size"]+4
220        )
221
222    @classmethod
223    def get_small_font(cls) -> Font:
224        """
225        Get the small font for use in the application.
226
227        Returns a modified `TkDefaultFont` with font size decreased by 2.
228        """
229        return font_utils.modify_named_font(
230            "TkDefaultFont", size=cls.get_base_font().actual()["size"]-2
231        )
232
233    @classmethod
234    def get_bold_font(cls) -> Font:
235        """
236        Get the bold font for use in the application.
237
238        Returns a modified `TkDefaultFont` with font weight set to bold.
239        """
240        return font_utils.modify_named_font("TkDefaultFont", weight="bold")
241
242    @classmethod
243    def get_fixed_font(cls) -> Font:
244        """
245        Get the monospace font for use in the application. Returns `TkFixedFont`.
246        """
247        return font.nametofont("TkFixedFont")