"""Shared app-wide constants: paths, palette, theme.

The palette and theming mirror SaraFem's Core.py (which mirrors SaraView's),
and read the same shared ~/.config/SaraSuite/Themes/*.toml files, so a theme
picked for one Sara program looks the same in all of them.
"""

import os
import sys
from dataclasses import asdict, dataclass, field
from pathlib import Path

import flet as ft
import tomlkit

AppName = "SaraSuite"
# Compared with the latest Gitea release to offer self-updates (SelfUpdate.py).
# Bump it, then run Packaging/Release.py, to publish a new SaraSuite.
AppVersion = "1.1.1"
IsFrozen = bool(getattr(sys, "frozen", False))  # running from the AppImage
# Bundled in assets/fonts and always registered, so it works as FontFamily
# without being installed. Any other FontFamily is looked up among the
# system's installed fonts.
BundledFontFamily = "Fixedsys Excelsior"
ActiveFontFamily = BundledFontFamily  # set by ApplyAppearance, read by BuildTheme

Home = Path.home()
ConfigHome = Home / ".config"
DataHome = Home / ".local" / "share"
CacheHome = Home / ".cache"

SharedConfigDir = ConfigHome / "SaraSuite"
ThemesDir = SharedConfigDir / "Themes"
ConfigDir = SharedConfigDir / "SaraSuite"
ConfigPath = ConfigDir / "Config.toml"
# Settings shared by every SaraSuite program (theme, font, window title bar).
# Same key names as the matching fields in each program's own Config.toml.
SharedConfigPath = SharedConfigDir / "Config.toml"

# Everything SaraSuite itself keeps about installed programs. Nothing in here
# is user-edited, so it's all fair game to delete when a program is removed.
DataDir = DataHome / "SaraSuite"
ProgramsDir = DataDir / "Programs"  # installed program files + venvs
ReceiptsDir = DataDir / "Receipts"  # what each install placed, for exact removal
PristineDir = DataDir / "Pristine"  # the default configs as last installed (merge base)
BackupsDir = DataDir / "Backups"  # displaced files and pre-merge config copies
DownloadsDir = CacheHome / "SaraSuite" / "Downloads"  # extracted source archives

# Bundled read-only files (program manifests, fonts). Inside a PyInstaller
# build they're unpacked to sys._MEIPASS rather than next to the code.
BundleDir = Path(getattr(sys, "_MEIPASS", Path(__file__).resolve().parent))
BundledManifestsDir = BundleDir / "Programs"  # the AppImage's own copy; see Catalog.py
AssetsDir = BundleDir / "assets"


class Palette:
    """Live values for the active theme (see ApplyTheme). Same attribute names
    and SaraView role mapping as SaraFem's Palette."""

    Mauve = "#cba6f7"
    Red = "#f38ba8"
    Peach = "#fab387"
    Yellow = "#f9e2af"
    Green = "#a6e3a1"
    Blue = "#89b4fa"
    Text = "#cdd6f4"
    White = "#cdd6f4"
    Overlay0 = "#6c7086"
    Surface1 = "#45475a"
    Surface0 = "#313244"
    Base = "#1e1e2e"
    Mantle = "#181825"
    Crust = "#11111b"


_ThemeRoleMap = {
    "Background": "Base", "Surface": "Mantle", "SurfaceAlt": "Surface0", "Border": "Surface1",
    "Text": "Text", "TextMuted": "Overlay0", "Black": "Crust", "White": "White",
    "Red": "Red", "Orange": "Peach", "Yellow": "Yellow", "Green": "Green",
    "Blue": "Blue", "Purple": "Mauve",
}


def ApplyTheme(ThemeName: str) -> None:
    """Mutate Palette in place from ~/.config/SaraSuite/Themes/<ThemeName>.toml.
    Falls back to the built-in Catppuccin Mocha values if the file is missing
    (SaraFem seeds that directory; SaraSuite only reads it). Must run before
    any control reads Palette.X."""
    ThemeFile = ThemesDir / f"{ThemeName}.toml"
    if not ThemeFile.exists():
        return
    try:
        RoleValues = tomlkit.parse(ThemeFile.read_text()).unwrap().get("Palette", {})
    except tomlkit.exceptions.TOMLKitError:
        return
    for RoleName, AttrName in _ThemeRoleMap.items():
        if RoleName in RoleValues:
            setattr(Palette, AttrName, RoleValues[RoleName])


@dataclass
class AppConfig:
    # True: Theme, FontFamily and HideWindowTitleBar come from the shared
    # ~/.config/SaraSuite/Config.toml (edited in SaraFem's Settings, SaraSuite
    # tab). False: SaraSuite uses its own values below instead.
    UseSharedSettings: bool = True
    Theme: str = "CatppuccinMocha"  # matches a file in ~/.config/SaraSuite/Themes/
    FontFamily: str = BundledFontFamily
    HideWindowTitleBar: bool = False
    # Where the Sara repos live (Gitea on SpineS); manifests
    # use it as {GitHost}.
    GitHost: str = "https://git.srhtnin.garden/sarah"
    # What the install dialog starts with, per program, overriding the
    # manifest's defaults: {Program: {OptionId: ticked}} and
    # {Program: {QuestionId: answer}}. Set in Settings.
    OptionDefaults: dict[str, dict[str, bool]] = field(default_factory=dict)
    AnswerDefaults: dict[str, dict[str, str]] = field(default_factory=dict)

    def Save(self) -> None:
        ConfigDir.mkdir(parents=True, exist_ok=True)
        ConfigPath.write_text(tomlkit.dumps(asdict(self)))


def LoadConfig() -> AppConfig:
    if not ConfigPath.exists():
        Config = AppConfig()
        Config.Save()
        return Config
    try:
        Data = tomlkit.parse(ConfigPath.read_text()).unwrap()
    except tomlkit.exceptions.TOMLKitError:
        return AppConfig()
    KnownFields = set(AppConfig.__dataclass_fields__)
    return AppConfig(**{Key: Value for Key, Value in Data.items() if Key in KnownFields})


@dataclass
class SharedSettings:
    """~/.config/SaraSuite/Config.toml, shared by every SaraSuite program.
    Same schema and fallback rules as SaraFem's SharedSettings."""

    Theme: str = "CatppuccinMocha"
    FontFamily: str = BundledFontFamily
    HideWindowTitleBar: bool = False

    def Save(self) -> None:
        SharedConfigDir.mkdir(parents=True, exist_ok=True)
        SharedConfigPath.write_text(tomlkit.dumps(asdict(self)))


def _OwnSettings(Config: AppConfig) -> SharedSettings:
    return SharedSettings(Config.Theme, Config.FontFamily, Config.HideWindowTitleBar)


def LoadSharedSettings(Config: AppConfig) -> SharedSettings:
    """The shared file, created from this program's own values if missing."""
    if not SharedConfigPath.exists():
        Shared = _OwnSettings(Config)
        Shared.Save()
        return Shared
    Result = _OwnSettings(Config)  # fallback for keys the file doesn't have
    try:
        Data = tomlkit.parse(SharedConfigPath.read_text()).unwrap()
    except tomlkit.exceptions.TOMLKitError:
        return Result
    for Key in SharedSettings.__dataclass_fields__:
        if Key in Data:
            setattr(Result, Key, Data[Key])
    return Result


def EffectiveSettings(Config: AppConfig) -> SharedSettings:
    return LoadSharedSettings(Config) if Config.UseSharedSettings else _OwnSettings(Config)


def ApplyAppearance(Settings: SharedSettings) -> None:
    """Theme colours and font; must run before anything reads Palette.X."""
    global ActiveFontFamily
    ApplyTheme(Settings.Theme)
    ActiveFontFamily = Settings.FontFamily or BundledFontFamily


def ChildEnvironment() -> dict[str, str]:
    """The environment for child processes (systemctl, pip, python3 -m venv).
    A PyInstaller build points LD_LIBRARY_PATH at its own bundled libraries
    and keeps the original in LD_LIBRARY_PATH_ORIG; system tools need the
    original back or they can load the wrong libraries."""
    Environment = dict(os.environ)
    if getattr(sys, "frozen", False):
        Original = Environment.pop("LD_LIBRARY_PATH_ORIG", None)
        if Original is not None:
            Environment["LD_LIBRARY_PATH"] = Original
        else:
            Environment.pop("LD_LIBRARY_PATH", None)
    for Key in ("PYTHONHOME", "PYTHONPATH"):
        Environment.pop(Key, None)
    return Environment


def CurrentDesktop() -> str:
    """First entry of $XDG_CURRENT_DESKTOP as-is (e.g. "COSMIC"), used for
    portal descriptors' UseIn= and the <desktop>-portals.conf file name."""
    return os.environ.get("XDG_CURRENT_DESKTOP", "").split(":")[0]


def BuildTheme() -> ft.Theme:
    ColorScheme = ft.ColorScheme(
        primary=Palette.Mauve,
        on_primary=Palette.Crust,
        primary_container=Palette.Surface0,
        on_primary_container=Palette.Mauve,
        secondary=Palette.Mauve,
        on_secondary=Palette.Crust,
        secondary_container=Palette.Surface0,
        on_secondary_container=Palette.Mauve,
        surface=Palette.Base,
        on_surface=Palette.Text,
        on_surface_variant=Palette.Overlay0,
        surface_container=Palette.Mantle,
        surface_container_low=Palette.Mantle,
        surface_container_high=Palette.Surface0,
        surface_container_highest=Palette.Surface1,
        outline=Palette.Surface1,
        outline_variant=Palette.Surface1,
        error=Palette.Red,
        on_error=Palette.Crust,
    )
    return ft.Theme(
        font_family=ActiveFontFamily,
        color_scheme=ColorScheme,
        use_material3=True,
        scaffold_bgcolor=Palette.Base,
        canvas_color=Palette.Base,
        dialog_theme=ft.DialogTheme(
            bgcolor=Palette.Mantle,
            shape=ft.RoundedRectangleBorder(radius=8, side=ft.BorderSide(1, Palette.Mauve)),
            title_text_style=ft.TextStyle(color=Palette.Mauve, size=18, font_family=ActiveFontFamily),
        ),
    )


def ChipButtonStyle(Accent: str = "") -> ft.ButtonStyle:
    """SaraView's button look: SurfaceAlt fill, 1px accent border, small radius.
    Accent defaults to Mauve; Remove buttons pass Palette.Red. Disabled buttons
    are greyed out (muted text, plain border, no fill) so it's obvious they
    can't be pressed."""
    Disabled = ft.ControlState.DISABLED
    Default = ft.ControlState.DEFAULT
    return ft.ButtonStyle(
        color={Disabled: Palette.Overlay0, Default: Palette.Text},
        bgcolor={Disabled: Palette.Mantle, Default: Palette.Surface0},
        side={Disabled: ft.BorderSide(1, Palette.Surface1), Default: ft.BorderSide(1, Accent or Palette.Mauve)},
        shape=ft.RoundedRectangleBorder(radius=4),
    )