1 files changed, 79 insertions, 0 deletions
diff --git a/ptpython/prompt_style.py b/ptpython/prompt_style.py
new file mode 100644
index 0000000..96b738f
--- /dev/null
+++ b/ptpython/prompt_style.py
@@ -0,0 +1,79 @@
+from __future__ import annotations
+
+from abc import ABCMeta, abstractmethod
+from typing import TYPE_CHECKING
+
+from prompt_toolkit.formatted_text import AnyFormattedText
+
+if TYPE_CHECKING:
+    from .python_input import PythonInput
+
+__all__ = ["PromptStyle", "IPythonPrompt", "ClassicPrompt"]
+
+
+class PromptStyle(metaclass=ABCMeta):
+    """
+    Base class for all prompts.
+    """
+
+    @abstractmethod
+    def in_prompt(self) -> AnyFormattedText:
+        "Return the input tokens."
+        return []
+
+    @abstractmethod
+    def in2_prompt(self, width: int) -> AnyFormattedText:
+        """
+        Tokens for every following input line.
+
+        :param width: The available width. This is coming from the width taken
+                      by `in_prompt`.
+        """
+        return []
+
+    @abstractmethod
+    def out_prompt(self) -> AnyFormattedText:
+        "Return the output tokens."
+        return []
+
+
+class IPythonPrompt(PromptStyle):
+    """
+    A prompt resembling the IPython prompt.
+    """
+
+    def __init__(self, python_input: PythonInput) -> None:
+        self.python_input = python_input
+
+    def in_prompt(self) -> AnyFormattedText:
+        return [
+            ("class:in", "In ["),
+            ("class:in.number", "%s" % self.python_input.current_statement_index),
+            ("class:in", "]: "),
+        ]
+
+    def in2_prompt(self, width: int) -> AnyFormattedText:
+        return [("class:in", "...: ".rjust(width))]
+
+    def out_prompt(self) -> AnyFormattedText:
+        return [
+            ("class:out", "Out["),
+            ("class:out.number", "%s" % self.python_input.current_statement_index),
+            ("class:out", "]:"),
+            ("", " "),
+        ]
+
+
+class ClassicPrompt(PromptStyle):
+    """
+    The classic Python prompt.
+    """
+
+    def in_prompt(self) -> AnyFormattedText:
+        return [("class:prompt", ">>> ")]
+
+    def in2_prompt(self, width: int) -> AnyFormattedText:
+        return [("class:prompt.dots", "...")]
+
+    def out_prompt(self) -> AnyFormattedText:
+        return []