"""SaraView's desktop client: browse and edit files in a local root directory,
or on a SaraView server (the one on SpineS) through its API. Laid out like
SaraFem: a directory tree on the left, the file list (or an open file) on
the right."""

import os
import subprocess
import sys
from typing import Optional

import flet as ft

from App import App
from Browser import Browser
from Core import (
    AppName, ApplyAppearance, AssetsDir, BuildTheme, BundledFontFamily, EffectiveSettings, LoadConfig, Palette,
    ResizeHandle,
)
from Filetree import Filetree
from Settings import ShowSettingsDialog


def _SetCursorThemeFallback() -> None:
    """GTK reads XCURSOR_THEME directly and doesn't always inherit it (shows as
    'Unable to load ... from the cursor theme'). Same fix as SaraFem's."""
    if os.environ.get("XCURSOR_THEME") or sys.platform == "win32":  # GTK/GNOME only
        return
    try:
        Result = subprocess.run(["gsettings", "get", "org.gnome.desktop.interface", "cursor-theme"],
                                capture_output=True, text=True, timeout=2)
        Theme = Result.stdout.strip().strip("'")
    except (OSError, subprocess.SubprocessError):
        Theme = ""
    os.environ["XCURSOR_THEME"] = Theme or "Adwaita"


def Main(Page: ft.Page) -> None:
    Config = LoadConfig()
    Appearance = EffectiveSettings(Config)
    ApplyAppearance(Appearance)  # before anything reads Palette.X

    Page.title = AppName
    Page.theme_mode = ft.ThemeMode.DARK
    Page.theme = BuildTheme()
    Page.dark_theme = BuildTheme()
    Page.fonts = {BundledFontFamily: "fonts/Fixedsys_Excelsior_Regular.ttf"}
    Page.window.title_bar_hidden = Appearance.HideWindowTitleBar
    Page.padding = 0
    Page.bgcolor = Palette.Base
    Page.window.width = 1180
    Page.window.height = 760
    if sys.platform == "win32":
        Page.window.icon = str(AssetsDir / "Icon.ico")  # taskbar/title bar (Linux: the desktop entry)
    Page.window.min_width = 720
    Page.window.min_height = 480

    TheApp = App(Page, Config)

    def OnPathChanged(Root: Optional[str], RelativePath: str, Reload: bool) -> None:
        if Reload:  # directories may have moved, so the tree starts over
            Tree.Reload()
        Tree.RevealPath(Root, RelativePath)

    def ShowSettings(Category: str = "General") -> None:
        ShowSettingsDialog(TheApp, OnSettingsSaved, Category)

    def OnSettingsSaved(Reconnect: bool) -> None:
        Tree.visible = Divider.visible = Config.ShowSidebar
        Tree.SetEntryButtons(TheBrowser.EntryButtons, Config.NewEntryButtonsAtTop, Update=False)
        if Reconnect:
            TheApp.Connect()  # its listeners reload the tree and the browser
        else:
            Body.update()
            Tree.Reload()  # "Show files in the tree" may have changed
            TheBrowser.Refresh()
            Tree.RevealPath(TheBrowser.Root, TheBrowser.Path)

    def ToggleSidebar() -> None:
        Config.ShowSidebar = not Config.ShowSidebar
        Config.Save()
        Tree.visible = Divider.visible = Config.ShowSidebar
        Body.update()

    def OnDrag(Delta: float) -> None:
        Tree.width = max(140, (Tree.width or Config.SidebarWidth) + Delta)
        Tree.update()

    def OnDragEnd() -> None:
        Config.SidebarWidth = int(Tree.width)
        Config.Save()

    TheBrowser = Browser(TheApp, OnPathChanged,
                         lambda Category=None: ShowSettings(Category or ("Connection" if TheApp.ConnectError else "General")),
                         ToggleSidebar)
    Tree = Filetree(TheApp, TheBrowser.OpenDirectory, TheBrowser.OpenFile)
    Tree.SetEntryButtons(TheBrowser.EntryButtons, Config.NewEntryButtonsAtTop, Update=False)
    Divider = ResizeHandle(OnDrag, OnDragEnd)
    Tree.visible = Divider.visible = Config.ShowSidebar
    # STRETCH so the divider gets the full height to be dragged along.
    Body = ft.Row([Tree, Divider, TheBrowser], expand=True, spacing=0, vertical_alignment=ft.CrossAxisAlignment.STRETCH)
    Page.add(Body)

    def OnSourceChanged() -> None:
        Tree.Reload()
        TheBrowser.SourceChanged()

    TheApp.Listeners.append(OnSourceChanged)
    TheApp.Connect()


if __name__ == "__main__":
    _SetCursorThemeFallback()
    ft.run(Main, assets_dir=str(AssetsDir))