import asyncio
import math
import select
import sys
import termios
import tty
import vtk
from vtk.util import numpy_support
import numpy as np
from io import BytesIO
from PIL import Image

import pyvista as pv

import kitty


class TerminalPlotter(pv.Plotter):
    def __init__(self, width, height, **kwargs):
        super().__init__(off_screen=True, window_size=(width, height), **kwargs)
        self.width = width
        self.height = height
        self._running = True
        self.w2i_filter = vtk.vtkWindowToImageFilter()
        self.w2i_filter.SetInputBufferTypeToRGBA()
        self.w2i_filter.ReadFrontBufferOff()
        self.w2i_filter.SetInput(self.ren_win)
        self.set_background([0.0, 0.0, 0.0])
        # transparency
        self.ren_win.SetAlphaBitPlanes(1)
        self.ren_win.SetMultiSamples(0)

    async def initialize(self):
        h_pix, _ = await kitty.get_terminal_cell_size()
        self.rows, _ = kitty.get_terminal_size()
        self.start_y, self.start_x = await kitty.get_position()
        self.needed_lines = math.ceil(self.height / h_pix)

        # Add vertical space if needed
        if self.rows - self.start_y < self.needed_lines:
            missing = self.needed_lines - (self.rows - self.start_y)
            self.start_y -= missing
            print("\n" * self.needed_lines, end="")
            kitty.set_position(self.start_y, self.start_x)

    async def _handle_key(self, c):
        if c == "a":
            self.camera.Azimuth(10)
        elif c == "d":
            self.camera.Azimuth(-10)
        elif c == "w":
            self.camera.Elevation(10)
        elif c == "s":
            self.camera.Elevation(-10)
        elif c == "+":
            self.camera.zoom(1.1)
        elif c == "-":
            self.camera.zoom(0.9)

    async def _input_loop(self):
        fd = sys.stdin.fileno()
        old_settings = termios.tcgetattr(fd)
        try:
            tty.setcbreak(fd)
            while self._running:
                rlist, _, _ = select.select([sys.stdin], [], [], 0)
                if rlist:
                    c = sys.stdin.read(1)
                    if c == "q":  # quit on q
                        self._running = False
                    else:
                        await self._handle_key(c)
                await asyncio.sleep(0.01)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)

    async def _render_loop(self):
        while self._running:
            # keep renedring the scene
            self.ren_win.Render()
            # Update the filter to grab the current buffer
            self.w2i_filter.Modified()
            self.w2i_filter.Update()

            vtk_image = self.w2i_filter.GetOutput()

            width, height, _ = vtk_image.GetDimensions()
            vtk_array = vtk_image.GetPointData().GetScalars()
            arr = numpy_support.vtk_to_numpy(vtk_array)

            # Reshape the array to height x width x channels (probably 3 or 4)
            arr = arr.reshape(height, width, -1)

            # Flip vertically because VTK's origin is bottom-left
            arr = np.flip(arr, axis=0)
            img = Image.fromarray(arr)
            buffer: BytesIO = BytesIO()
            img.save(buffer, format="PNG")
            await kitty.draw_to_terminal(buffer)
            kitty.set_position(self.start_y, self.start_x)

    async def run(self):
        await self.initialize()
        self.iren.initialize()
        tasks = [
            asyncio.create_task(self._input_loop()),
            asyncio.create_task(self._render_loop()),
        ]
        await asyncio.wait(tasks, return_when=asyncio.FIRST_COMPLETED)
        self._running = False