Py.Cafe

from typing import Optional

import ipympl.backend_nbagg as ipympl
import matplotlib.pyplot as plt
import numpy as np
from matplotlib.axes import Axes
from matplotlib.figure import Figure

import solara
plt.switch_backend("module://ipympl.backend_nbagg")


@solara.component_vue("viewlistener.vue")
def ViewListener(view_data=None, on_view_data=None, children=[], style={}):
    ...


def use_matplotlib_zoom(fig: Optional[Figure], ax: Optional[Axes], scale=2.0, reverse=True, disable=False):
    def connect():
        if disable:
            return
        if fig is None:
            return
        if ax is None:
            return

        def zoom(event):
            assert ax is not None
            xlim = ax.get_xlim()
            ylim = ax.get_ylim()

            xdata = event.xdata  # get event x location
            ydata = event.ydata  # get event y location

            if event.button == "down":
                # zoom in
                scale_factor = 1 / scale
            elif event.button == "up":
                # zoom our
                scale_factor = scale
            else:
                raise ValueError(f"Unknown button: {event.button}")

            if reverse:
                scale_factor = 1 / scale_factor

            width = (xlim[1] - xlim[0]) * scale_factor
            height = (ylim[1] - ylim[0]) * scale_factor

            relx = (xlim[1] - xdata) / (xlim[1] - xlim[0])
            rely = (ylim[1] - ydata) / (ylim[1] - ylim[0])

            ax.set_xlim([xdata - width * (1 - relx), xdata + width * (relx)])
            ax.set_ylim([ydata - height * (1 - rely), ydata + height * (rely)])
            ax.figure.canvas.draw()

        cid = fig.canvas.mpl_connect("scroll_event", zoom)
        # print("connected", cid)
        def cleanup():
            if fig is None:
                return
            fig.canvas.mpl_disconnect(cid)

        return cleanup

    solara.use_effect(connect, [fig, ax, scale, disable])


def use_matplotlib_pan(fig: Optional[Figure], ax: Optional[Axes], scale=2.0, disable=False):
    def connect():
        if disable:
            return
        if fig is None:
            return
        if ax is None:
            return

        xlim = ax.get_xlim()
        ylim = ax.get_ylim()
        x_start = 0
        y_start = 0
        dragging = False

        def mouse_down(event):
            nonlocal xlim, ylim, x_start, y_start, dragging
            if ax is None:
                return
            if event.inaxes != ax:
                return
            xlim = ax.get_xlim()
            ylim = ax.get_ylim()
            x_start = event.xdata
            y_start = event.ydata
            dragging = True

        def mouse_up(event):
            nonlocal dragging
            dragging = False
            if fig is not None:
                fig.canvas.draw()

        def mouse_move(event):
            nonlocal xlim, ylim
            if ax is None or fig is None:
                return
            if not dragging:
                return

            if event.inaxes != ax:
                return
            dx = event.xdata - x_start
            dy = event.ydata - y_start
            print(dx, dy)
            # mutate, because the event coordinates are
            # relative to the current limits
            xlim -= dx
            ylim -= dy
            ax.set_xlim(xlim)
            ax.set_ylim(ylim)

            fig.canvas.draw()

        # attach the call back
        cid1 = fig.canvas.mpl_connect("button_press_event", mouse_down)
        cid2 = fig.canvas.mpl_connect("button_release_event", mouse_up)
        cid3 = fig.canvas.mpl_connect("motion_notify_event", mouse_move)

        def cleanup():
            if fig is None:
                return
            fig.canvas.mpl_disconnect(cid1)
            fig.canvas.mpl_disconnect(cid2)
            fig.canvas.mpl_disconnect(cid3)

        return cleanup

    solara.use_effect(connect, [fig, ax, scale, disable])


@solara.component
def Plot1(seed: int = 42):
    view_data = solara.use_reactive({"width": 800, "height": 600})
    width, height = view_data.value["width"], view_data.value["height"]
    dpi = 100  # doesn't really matter, we work in pixels
    #plt.switch_backend("module://ipympl.backend_nbagg")
    # it is important to create the figure just once, since we do not want to create
    # the canvas (which is a widget) every time we render the component
    def make():
        fig = plt.figure(figsize=(width / dpi, height / dpi), dpi=dpi)
        # import traceback
        # used this to debug why call was closed
        # def myclose():
        #     traceback.print_stack()
        #     print("Why was close called?")
        # fig.canvas.close = myclose
        print(fig.canvas)
        return fig
    fig = solara.use_memo(make, [])
    assert isinstance(fig.canvas, ipympl.Canvas)
    fig.canvas.header_visible = False
    fig.canvas.resizable = False  # does not make sense if we use a responsive layout
    # fig.canvas.capture_scroll = True

    fig.set_size_inches(width / dpi, height / dpi)
    # because we reuse the figure, we need to clear it
    fig.clear()
    ax = fig.subplots()
    ax.clear()
    # financial data random walk
    np.random.seed(seed)
    returns = 0.01 * np.random.randn(1000).cumsum() + 0.05
    ax.plot(returns)

    # some custom hooks to enable zooming and panning
    # but you can also use the ipympl toolbar
    # use_matplotlib_zoom(fig, ax, scale=1.3)
    # use_matplotlib_pan(fig, ax, scale=1.3)
    # sometimes needed to avoid some draw artifacts
    # fig.canvas._force_full = True
    fig.canvas.draw()
    with ViewListener(view_data=view_data.value, on_view_data=view_data.set, style={"width": "100%", "height": "40vh"}):
        FigureMatplotlib(fig)


def use_ipympl_size_fix(fig: Figure, disable=False):
    width_inch, height_inch = fig.get_size_inches()
    dpi = fig.get_dpi()
    width, height = int(width_inch * dpi), int(height_inch * dpi)

    def update_size():
        if disable:
            return
        assert fig is not None
        canvas_widget = fig.canvas
        if isinstance(canvas_widget, ipympl.Canvas):
            # when using ipympl, we force the size
            canvas_widget.layout.width = f"{width}px"
            canvas_widget.layout.height = f"{height}px"

    solara.use_effect(update_size, [width, height])


@solara.component
def FigureMatplotlib(fig: Figure):
    use_ipympl_size_fix(fig)
    # reacton is picky about wanting to have an element as return type
    # so we wrap the canvas widget in a column
    return solara.Column(children=[fig.canvas], style={"height": "100%"})



seed = solara.reactive(42)


@solara.component
def Page():
    with solara.Sidebar():
        with solara.Card("Seed"):
            solara.SliderInt("seed", seed, min=0, max=1000, step=1)

    with solara.ColumnsResponsive(12, 12, 6):
        with solara.Card("This months profits"):
            Plot1(seed.value)
            pass
        with solara.Card("This months expenses"):
            print("Plot2", seed.value)
            Plot1(seed.value + 1)

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