"""SaraSuite entry point: installs, updates and removes Sara programs.
With arguments it runs the command-line mode instead (see Cli.py)."""

import os
import shutil
import sys
import traceback
from typing import Callable

import flet as ft

from Core import (
    AppName, ApplyTheme, AssetsDir, BuildTheme, ChipButtonStyle, DataDir, DataHome, FontFamily,
    LoadConfig, Palette,
)
from Dialogs import ShowInstallDialog, ShowRemoveDialog, ShowUpdateDialog
from Installer import Apply, Fetch, GetStatus, PlanConfigs, PlanRemoval, Remove, SourceVersion
from Manifests import LoadPrograms
from ProgramCard import ProgramCard

_MaxLogLines = 2000

# When running as an AppImage, SaraSuite can put itself in the app menu.
_AppImage = os.environ.get("APPIMAGE", "")
_MenuEntry = DataHome / "applications" / "SaraSuite.desktop"
_MenuIcon = DataDir / "SaraSuite.png"


def _SetMenuEntry(Enabled: bool) -> None:
    if not Enabled:
        _MenuEntry.unlink(missing_ok=True)
        _MenuIcon.unlink(missing_ok=True)
        return
    _MenuIcon.parent.mkdir(parents=True, exist_ok=True)
    shutil.copy(AssetsDir / "Icon.png", _MenuIcon)
    _MenuEntry.parent.mkdir(parents=True, exist_ok=True)
    _MenuEntry.write_text(
        "[Desktop Entry]\nType=Application\nName=SaraSuite\n"
        "Comment=Install, update and remove Sara programs\n"
        f"Exec={_AppImage}\nIcon={_MenuIcon}\nTerminal=false\n"
        "Categories=System;Settings;\nStartupNotify=true\n"
    )


def Main(Page: ft.Page) -> None:
    Config = LoadConfig()
    ApplyTheme(Config.Theme)  # must run before anything reads Palette.X

    Page.title = AppName
    Page.theme_mode = ft.ThemeMode.DARK
    Page.theme = BuildTheme()
    Page.dark_theme = BuildTheme()
    Page.fonts = {FontFamily: "fonts/Fixedsys_Excelsior_Regular.ttf"}
    Page.padding = 0
    Page.bgcolor = Palette.Base
    Page.window.width = 960
    Page.window.height = 720

    LogView = ft.ListView(expand=True, auto_scroll=True, spacing=0, padding=8)

    def Log(Line: str) -> None:
        if Line.startswith("=="):
            Color = Palette.Mauve
        elif Line.startswith("Error"):
            Color = Palette.Red
        elif Line.startswith(("$", "  ")):
            Color = Palette.Overlay0
        else:
            Color = Palette.Text
        LogView.controls.append(ft.Text(Line, size=12, color=Color, selectable=True))
        if len(LogView.controls) > _MaxLogLines:
            del LogView.controls[: len(LogView.controls) - _MaxLogLines]
        LogView.update()

    Programs = LoadPrograms()
    Cards: list[ProgramCard] = []
    State = {"Busy": False}

    def RefreshCard(Card: ProgramCard) -> None:
        try:
            Current = GetStatus(Card.Program)
            Leftovers = PlanRemoval(Card.Program)
        except Exception as Error:
            Log(f"Error checking {Card.Program.Name}: {Error}")
            return
        Card.ShowStatus(Current, Leftovers, State["Busy"])
        Card.update()

    def RefreshAll() -> None:
        for Card in Cards:
            RefreshCard(Card)

    def SetBusy(Busy: bool, Working: ProgramCard | None = None) -> None:
        State["Busy"] = Busy
        RefreshButton.disabled = Busy
        for Card in Cards:
            Card.SetBusy(Busy, Card is Working)
            Card.update()
        RefreshButton.update()

    def RunOperation(Card: ProgramCard | None, Work: Callable[[], None]) -> None:
        """Run Work in a background thread with every card locked, then
        refresh the card's status. Only one operation runs at a time."""
        if State["Busy"]:
            return
        SetBusy(True, Card)

        def Worker() -> None:
            try:
                Work()
            except Exception as Error:
                Log(f"Error: {Error}")
                for Line in traceback.format_exc().rstrip().splitlines():
                    Log(f"  {Line}")
            finally:
                SetBusy(False)
                RefreshAll()

        Page.run_thread(Worker)

    def OnInstall(Card: ProgramCard) -> None:
        Program = Card.Program
        ShowInstallDialog(
            Page, Program,
            lambda Options, Answers: RunOperation(Card, lambda: Apply(Program, Log, Options, Answers)),
        )

    def OnUpdate(Card: ProgramCard) -> None:
        # Download the new commit and plan the config merges first, so the
        # dialog shows exactly what the update will do; Apply then installs
        # that same download.
        def Prepare() -> None:
            Program = Card.Program
            Source = Fetch(Program, Log)
            Current = GetStatus(Program)
            Plans = PlanConfigs(Program, Source.Dir, Current.Receipt.Answers)
            SetBusy(False)
            ShowUpdateDialog(
                Page, Program, Current, SourceVersion(Program, Source.Dir), Source.Commit, Plans,
                lambda: RunOperation(Card, lambda: Apply(Program, Log, Source=Source)),
            )

        RunOperation(Card, Prepare)

    def OnRemove(Card: ProgramCard) -> None:
        Program = Card.Program
        Installed = Card.CurrentStatus is not None and Card.CurrentStatus.Installed
        ShowRemoveDialog(
            Page, Program, PlanRemoval(Program), Installed,
            lambda RemoveConfigs, RemoveRuntime: RunOperation(
                Card, lambda: Remove(Program, RemoveConfigs, RemoveRuntime, Log),
            ),
        )

    for Program in Programs:
        Cards.append(ProgramCard(Program, OnInstall, OnUpdate, OnRemove))

    def ToggleMenuEntry(e) -> None:
        _SetMenuEntry(not _MenuEntry.exists())
        MenuButton.content = "Remove from app menu" if _MenuEntry.exists() else "Add to app menu"
        MenuButton.update()

    MenuButton = ft.OutlinedButton(
        content="Remove from app menu" if _MenuEntry.exists() else "Add to app menu",
        style=ChipButtonStyle(),
        visible=bool(_AppImage),
        on_click=ToggleMenuEntry,
    )

    RefreshButton = ft.IconButton(
        icon=ft.Icons.REFRESH,
        icon_color=Palette.Mauve,
        tooltip="Check for updates",
        on_click=lambda e: RunOperation(None, RefreshAll),
    )

    Page.add(
        ft.Column(
            expand=True,
            spacing=0,
            controls=[
                ft.Container(
                    content=ft.Row([
                        ft.Text(AppName, size=24, color=Palette.Mauve),
                        ft.Container(expand=True),
                        MenuButton,
                        RefreshButton,
                    ]),
                    padding=ft.Padding.symmetric(horizontal=16, vertical=8),
                    bgcolor=Palette.Mantle,
                    border=ft.Border.only(bottom=ft.BorderSide(1, Palette.Surface1)),
                ),
                ft.ListView(Cards, expand=True, spacing=12, padding=16),
                ft.Container(
                    content=LogView,
                    height=200,
                    bgcolor=Palette.Crust,
                    border=ft.Border.only(top=ft.BorderSide(1, Palette.Surface1)),
                ),
            ],
        )
    )
    Page.run_thread(RefreshAll)


if __name__ == "__main__":
    if len(sys.argv) > 1:
        from Cli import Run

        sys.exit(Run(sys.argv[1:]))
    ft.run(Main, assets_dir=str(AssetsDir))