import os
import sys
from rich.console import RenderableType

from rich.syntax import Syntax
from rich.traceback import Traceback

from textual import events
from textual.app import App
from textual.widgets import Header, Footer, FileClick, ScrollView, DirectoryTree


class MyApp(App):
    """An example of a very simple Textual App"""

    async def on_load(self, event: events.Load) -> None:
        """Sent before going in to application mode."""

        # Bind our basic keys
        await self.bind("b", "view.toggle('sidebar')", "Toggle sidebar")
        await self.bind("q", "quit", "Quit")

        # Get path to show
        try:
            self.path = sys.argv[1]
        except IndexError:
            self.path = os.path.abspath(
                os.path.join(os.path.basename(__file__), "../../")
            )

    async def on_mount(self, event: events.Mount) -> None:
        """Call after terminal goes in to application mode"""

        # Create our widgets
        # In this a scroll view for the code and a directory tree
        self.body = ScrollView()
        self.directory = DirectoryTree(self.path, "Code")

        # Dock our widgets
        await self.view.dock(Header(), edge="top")
        await self.view.dock(Footer(), edge="bottom")

        # Note the directory is also in a scroll view
        await self.view.dock(
            ScrollView(self.directory), edge="left", size=32, name="sidebar"
        )
        await self.view.dock(self.body, edge="top")

    async def message_file_click(self, message: FileClick) -> None:
        """A message sent by the directory tree when a file is clicked."""

        syntax: RenderableType
        try:
            # Construct a Syntax object for the path in the message
            syntax = Syntax.from_path(
                message.path,
                line_numbers=True,
                word_wrap=True,
                indent_guides=True,
                theme="monokai",
            )
        except Exception:
            # Possibly a binary file
            # For demonstration purposes we will show the traceback
            syntax = Traceback(theme="monokai", width=None, show_locals=True)
        self.app.sub_title = os.path.basename(message.path)
        await self.body.update(syntax)


# Run our app class
MyApp.run(title="Code Viewer", log="textual.log")