Add history/undo

ChangeLog.md

@@ -12,6 +12,8 @@
   the zoom level. ([#14](https://github.com/davep/complexitty/issues/14))
 - Added `CopyCommandLineToClipboard`.
   ([#20](https://github.com/davep/complexitty/pull/20))
+- Added the ability to undo a change in the plot.
+  ([#21](https://github.com/davep/complexitty/pull/21))
 
 ## v0.2.0
 

pyproject.toml

@@ -7,7 +7,7 @@ authors = [
 ]
 dependencies = [
     "textual>=3.1.0",
-    "textual-enhanced>=0.11.0",
+    "textual-enhanced>=0.13.0",
     "textual-canvas>=0.3.0",
     "xdg-base-dirs>=6.0.2",
 ]

requirements-dev.lock

@@ -12,7 +12,7 @@
 -e file:.
 aiohappyeyeballs==2.6.1
     # via aiohttp
-aiohttp==3.11.16
+aiohttp==3.11.18
     # via aiohttp-jinja2
     # via textual-dev
     # via textual-serve
@@ -42,12 +42,12 @@ distlib==0.3.9
     # via virtualenv
 filelock==3.18.0
     # via virtualenv
-frozenlist==1.5.0
+frozenlist==1.6.0
     # via aiohttp
     # via aiosignal
 ghp-import==2.1.0
     # via mkdocs
-identify==2.6.9
+identify==2.6.10
     # via pre-commit
 idna==3.10
     # via requests
@@ -91,11 +91,11 @@ multidict==6.4.3
     # via aiohttp
     # via yarl
 mypy==1.15.0
-mypy-extensions==1.0.0
+mypy-extensions==1.1.0
     # via mypy
 nodeenv==1.9.1
     # via pre-commit
-packaging==24.2
+packaging==25.0
     # via mkdocs
 paginate==0.5.7
     # via mkdocs-material
@@ -132,7 +132,7 @@ rich==14.0.0
     # via textual-serve
 six==1.17.0
     # via python-dateutil
-textual==3.1.0
+textual==3.1.1
     # via complexitty
     # via textual-canvas
     # via textual-dev
@@ -141,7 +141,7 @@ textual==3.1.0
 textual-canvas==0.4.0
     # via complexitty
 textual-dev==1.7.0
-textual-enhanced==0.12.0
+textual-enhanced==0.13.0
     # via complexitty
 textual-serve==1.1.2
     # via textual-dev

requirements.lock

@@ -26,13 +26,13 @@ pygments==2.19.1
     # via rich
 rich==14.0.0
     # via textual
-textual==3.1.0
+textual==3.1.1
     # via complexitty
     # via textual-canvas
     # via textual-enhanced
 textual-canvas==0.4.0
     # via complexitty
-textual-enhanced==0.12.0
+textual-enhanced==0.13.0
     # via complexitty
 typing-extensions==4.13.2
     # via textual

src/complexitty/commands/__init__.py

@@ -11,7 +11,7 @@
     SetColourToShadesOfGreen,
     SetColourToShadesOfRed,
 )
-from .main import CopyCommandLineToClipboard, Quit
+from .main import CopyCommandLineToClipboard, Quit, Undo
 from .navigation import (
     GoMiddle,
     GoTo,
@@ -68,6 +68,7 @@
     "SetColourToShadesOfBlue",
     "SetColourToShadesOfGreen",
     "SetColourToShadesOfRed",
+    "Undo",
     "ZeroZero",
     "ZoomIn",
     "ZoomInFaster",

src/complexitty/commands/main.py

@@ -21,4 +21,11 @@ class CopyCommandLineToClipboard(Command):
     BINDING_KEY = "c"
 
 
+##############################################################################
+class Undo(Command):
+    """Undo the latest change"""
+
+    BINDING_KEY = "backspace"
+
+
 ### main.py ends here

src/complexitty/providers/main.py

@@ -38,6 +38,7 @@
     SetColourToShadesOfBlue,
     SetColourToShadesOfGreen,
     SetColourToShadesOfRed,
+    Undo,
     ZeroZero,
     ZoomIn,
     ZoomInFaster,
@@ -84,6 +85,7 @@ def commands(self) -> CommandHits:
         yield SetColourToShadesOfBlue()
         yield SetColourToShadesOfGreen()
         yield SetColourToShadesOfRed()
+        yield Undo()
         yield ZeroZero()
         yield ZoomIn()
         yield ZoomInFaster()

src/complexitty/screens/main.py

@@ -5,7 +5,7 @@
 from argparse import Namespace
 from math import floor, log10
 from re import Pattern, compile
-from typing import Final
+from typing import Final, NamedTuple, TypeAlias
 
 ##############################################################################
 # Textual imports.
@@ -18,6 +18,7 @@
 from textual_enhanced.commands import ChangeTheme, Command, Help
 from textual_enhanced.dialogs import ModalInput
 from textual_enhanced.screen import EnhancedScreen
+from textual_enhanced.tools import History
 
 ##############################################################################
 # Local imports.
@@ -48,6 +49,7 @@
     SetColourToShadesOfBlue,
     SetColourToShadesOfGreen,
     SetColourToShadesOfRed,
+    Undo,
     ZeroZero,
     ZoomIn,
     ZoomInFaster,
@@ -58,6 +60,27 @@
 from ..providers import MainCommands
 
 
+##############################################################################
+class Situation(NamedTuple):
+    """A class to hold a particular situation we can undo to."""
+
+    x_position: float
+    """The X position in the plot."""
+    y_position: float
+    """The Y position in the plot."""
+    zoom: float
+    """The zoom level."""
+    max_iteration: int
+    """The maximum iteration."""
+    multibrot: float
+    """The multibrot setting."""
+
+
+##############################################################################
+PlotHistory: TypeAlias = History[Situation]
+"""Type of the plot history."""
+
+
 ##############################################################################
 class Main(EnhancedScreen[None]):
     """The main screen for the application."""
@@ -101,6 +124,7 @@ class Main(EnhancedScreen[None]):
         SetColourToShadesOfBlue,
         SetColourToShadesOfGreen,
         SetColourToShadesOfRed,
+        Undo,
         ZeroZero,
         ZoomIn,
         ZoomInFaster,
@@ -120,6 +144,8 @@ def __init__(self, arguments: Namespace) -> None:
         """
         self._arguments = arguments
         """The command line arguments passed to the application."""
+        self._history = PlotHistory()
+        """The plot situation history."""
         super().__init__()
 
     def compose(self) -> ComposeResult:
@@ -140,6 +166,7 @@ def on_mount(self) -> None:
             if self._arguments.colour_map is None
             else get_colour_map(self._arguments.colour_map),
         )
+        self._remember()
 
     @on(Mandelbrot.Plotted)
     def _update_situation(self, message: Mandelbrot.Plotted) -> None:
@@ -168,13 +195,27 @@ def _update_situation(self, message: Mandelbrot.Plotted) -> None:
             f"{message.elapsed:0.4f} seconds"
         )
 
+    def _remember(self) -> None:
+        """Remember the current situation."""
+        plot = self.query_one(Mandelbrot)
+        self._history.add(
+            Situation(
+                plot.x_position,
+                plot.y_position,
+                plot.zoom,
+                plot.max_iteration,
+                plot.multibrot,
+            )
+        )
+
     def action_zoom(self, change: float) -> None:
         """Change the zoom value.
 
         Args:
             change: The amount to change the zoom by.
         """
         self.query_one(Mandelbrot).zoom *= change
+        self._remember()
 
     def action_move(self, x: int, y: int) -> None:
         """Move the plot in the indicated direction.
@@ -184,6 +225,7 @@ def action_move(self, x: int, y: int) -> None:
             y: The number of pixels to move in the Y direction.
         """
         self.query_one(Mandelbrot).move(x, y)
+        self._remember()
 
     def action_iterate(self, change: int) -> None:
         """Change the maximum iteration.
@@ -192,6 +234,7 @@ def action_iterate(self, change: int) -> None:
             change: The change to make to the maximum iterations.
         """
         self.query_one(Mandelbrot).max_iteration += change
+        self._remember()
 
     def action_set_colour(self, colour_map: str) -> None:
         """Set the colour map for the plot.
@@ -208,6 +251,7 @@ def action_multibrot(self, change: int) -> None:
             change: The change to make to the 'multibrot' value.
         """
         self.query_one(Mandelbrot).multibrot += change
+        self._remember()
 
     def action_goto(self, x: int, y: int) -> None:
         """Go to a specific location.
@@ -217,10 +261,12 @@ def action_goto(self, x: int, y: int) -> None:
             y: The Y location to go to.
         """
         self.query_one(Mandelbrot).goto(x, y)
+        self._remember()
 
     def action_reset_command(self) -> None:
         """Reset the plot to its default values."""
         self.query_one(Mandelbrot).reset()
+        self._remember()
 
     _VALID_LOCATION: Final[Pattern[str]] = compile(
         r"(?P<x>[^, ]+) *[, ] *(?P<y>[^, ]+)"
@@ -270,5 +316,19 @@ def action_copy_command_line_to_clipboard_command(self) -> None:
         self.app.copy_to_clipboard(command)
         self.notify(command, title="Copied")
 
+    def action_undo_command(self) -> None:
+        """Undo through the history."""
+        if (
+            self._history.backward()
+            and (situation := self._history.current_item) is not None
+        ):
+            self.query_one(Mandelbrot).set(
+                x_position=situation.x_position,
+                y_position=situation.y_position,
+                zoom=situation.zoom,
+                max_iteration=situation.max_iteration,
+                multibrot=situation.multibrot,
+            ).plot()
+
 
 ### main.py ends here