from __future__ import annotations

import sys
from pathlib import Path

from PySide6.QtCore import Qt
from PySide6.QtGui import QColor, QPalette
from PySide6.QtWidgets import QApplication


ASSET_DIR = Path(__file__).resolve().parent / "assets"


def asset_url(name: str) -> str:
    return ASSET_DIR.joinpath(name).as_posix()


def apply_app_theme(theme: str) -> None:
    app = QApplication.instance()
    if app is None:
        return
    effective = effective_theme(theme)
    app.setStyle("Fusion")
    if effective == "dark":
        app.setPalette(dark_palette())
        app.setStyleSheet(dark_stylesheet())
    else:
        app.setPalette(light_palette())
        app.setStyleSheet(light_stylesheet())


def effective_theme(theme: str) -> str:
    if theme == "dark":
        return "dark"
    if theme == "light":
        return "light"
    return system_theme()


def system_theme() -> str:
    app = QApplication.instance()
    if app is not None:
        try:
            color_scheme = app.styleHints().colorScheme()
            if color_scheme == Qt.ColorScheme.Dark:
                return "dark"
            if color_scheme == Qt.ColorScheme.Light:
                return "light"
        except (AttributeError, TypeError):
            pass
    if sys.platform.startswith("win"):
        try:
            import winreg

            with winreg.OpenKey(
                winreg.HKEY_CURRENT_USER,
                r"Software\Microsoft\Windows\CurrentVersion\Themes\Personalize",
            ) as key:
                apps_use_light_theme, _ = winreg.QueryValueEx(key, "AppsUseLightTheme")
                return "light" if int(apps_use_light_theme) else "dark"
        except OSError:
            pass
    if app is not None:
        return "dark" if app.style().standardPalette().color(QPalette.Window).lightness() < 128 else "light"
    return "light"


def light_palette() -> QPalette:
    palette = QPalette()
    palette.setColor(QPalette.Window, QColor("#f8fafc"))
    palette.setColor(QPalette.WindowText, QColor("#111827"))
    palette.setColor(QPalette.Base, QColor("#ffffff"))
    palette.setColor(QPalette.AlternateBase, QColor("#f1f5f9"))
    palette.setColor(QPalette.ToolTipBase, QColor("#ffffff"))
    palette.setColor(QPalette.ToolTipText, QColor("#111827"))
    palette.setColor(QPalette.Text, QColor("#111827"))
    palette.setColor(QPalette.Button, QColor("#e5e7eb"))
    palette.setColor(QPalette.ButtonText, QColor("#111827"))
    palette.setColor(QPalette.Highlight, QColor("#c084fc"))
    palette.setColor(QPalette.HighlightedText, QColor("#111827"))
    return palette


def dark_palette() -> QPalette:
    palette = QPalette()
    palette.setColor(QPalette.Window, QColor("#1f1f1f"))
    palette.setColor(QPalette.WindowText, QColor("#f8fafc"))
    palette.setColor(QPalette.Base, QColor("#2b2b2b"))
    palette.setColor(QPalette.AlternateBase, QColor("#353535"))
    palette.setColor(QPalette.ToolTipBase, QColor("#111827"))
    palette.setColor(QPalette.ToolTipText, QColor("#f8fafc"))
    palette.setColor(QPalette.Text, QColor("#f8fafc"))
    palette.setColor(QPalette.Button, QColor("#2f2f2f"))
    palette.setColor(QPalette.ButtonText, QColor("#f8fafc"))
    palette.setColor(QPalette.Highlight, QColor("#c084fc"))
    palette.setColor(QPalette.HighlightedText, QColor("#111827"))
    return palette


def light_stylesheet() -> str:
    return """
        QWidget {
            background-color: #f8fafc;
            color: #111827;
            selection-background-color: #93c5fd;
            selection-color: #111827;
        }
        QGraphicsView {
            background-color: #ffffff;
            border: none;
        }
        QMenuBar {
            background-color: #f1f5f9;
            color: #111827;
        }
        QMenuBar::item {
            background: transparent;
            padding: 5px 10px;
        }
        QMenuBar::item:selected {
            background-color: #e2e8f0;
        }
        QMenu {
            background-color: #ffffff;
            color: #111827;
            border: 1px solid #cbd5e1;
        }
        QMenu::item {
            padding: 5px 24px 5px 24px;
        }
        QMenu::item:selected {
            background-color: #dbeafe;
        }
        QMenu::item:disabled {
            color: #94a3b8;
            background-color: transparent;
        }
        QMenu::item:selected:disabled {
            color: #94a3b8;
            background-color: transparent;
        }
        QPushButton, QToolButton {
            background-color: #e5e7eb;
            color: #111827;
            border: 1px solid #cbd5e1;
            border-radius: 4px;
            padding: 4px 8px;
        }
        QPushButton:hover, QToolButton:hover {
            background-color: #dbeafe;
        }
        QPushButton:disabled, QToolButton:disabled {
            background-color: #f1f5f9;
            color: #94a3b8;
            border-color: #e2e8f0;
        }
        QTreeWidget, QTableWidget, QListWidget, QLineEdit, QComboBox, QSpinBox {
            background-color: #ffffff;
            color: #111827;
            alternate-background-color: #f1f5f9;
            border: 1px solid #cbd5e1;
            border-radius: 4px;
            min-height: 24px;
            selection-background-color: #bfdbfe;
            selection-color: #111827;
        }
        QLineEdit, QComboBox, QSpinBox {
            padding: 2px 8px;
        }
        QComboBox {
            padding-right: 28px;
        }
        QComboBox:hover, QSpinBox:hover, QLineEdit:hover {
            border-color: #94a3b8;
        }
        QComboBox:focus, QSpinBox:focus, QLineEdit:focus {
            border-color: #60a5fa;
        }
        QComboBox::drop-down {
            subcontrol-origin: padding;
            subcontrol-position: top right;
            width: 24px;
            border-left: 1px solid #cbd5e1;
            border-top-right-radius: 4px;
            border-bottom-right-radius: 4px;
            background-color: #f1f5f9;
        }
        QComboBox::drop-down:hover {
            background-color: #e2e8f0;
        }
        QComboBox::down-arrow {
            image: url("__INPUT_DOWN_ARROW__");
            width: 10px;
            height: 10px;
        }
        QSpinBox {
            padding-right: 28px;
        }
        QSpinBox::up-button, QSpinBox::down-button {
            subcontrol-origin: border;
            width: 24px;
            border-left: 1px solid #cbd5e1;
            background-color: #f1f5f9;
        }
        QSpinBox::up-button {
            subcontrol-position: top right;
            border-top-right-radius: 4px;
        }
        QSpinBox::down-button {
            subcontrol-position: bottom right;
            border-bottom-right-radius: 4px;
        }
        QSpinBox::up-button:hover, QSpinBox::down-button:hover {
            background-color: #e2e8f0;
        }
        QSpinBox::up-arrow {
            image: url("__INPUT_UP_ARROW__");
            width: 10px;
            height: 10px;
        }
        QSpinBox::down-arrow {
            image: url("__INPUT_DOWN_ARROW__");
            width: 10px;
            height: 10px;
        }
        QComboBox QAbstractItemView {
            background-color: #ffffff;
            color: #111827;
            border: 1px solid #cbd5e1;
            selection-background-color: #bfdbfe;
            selection-color: #111827;
        }
        QHeaderView::section {
            background-color: #e5e7eb;
            color: #111827;
            border: 1px solid #cbd5e1;
            padding: 4px;
        }
        QSplitter::handle {
            background-color: #e2e8f0;
        }
        QStatusBar {
            background-color: #f1f5f9;
            color: #111827;
        }
        QToolTip {
            background-color: #ffffff;
            color: #111827;
            border: 1px solid #cbd5e1;
        }
        QScrollBar:vertical {
            background: #f1f5f9;
            width: 12px;
            margin: 12px 0 12px 0;
            border: none;
        }
        QScrollBar::handle:vertical {
            background: #94a3b8;
            min-height: 28px;
            margin: 0 4px;
            border-radius: 2px;
        }
        QScrollBar::handle:vertical:hover {
            background: #64748b;
            margin: 0 2px;
            border-radius: 4px;
        }
        QScrollBar::add-page:vertical,
        QScrollBar::sub-page:vertical {
            background: transparent;
            border: none;
            height: 0;
        }
        QScrollBar::sub-line:vertical,
        QScrollBar::add-line:vertical {
            background: #f1f5f9;
            border: none;
            height: 12px;
            subcontrol-origin: margin;
        }
        QScrollBar::sub-line:vertical {
            subcontrol-position: top;
        }
        QScrollBar::add-line:vertical {
            subcontrol-position: bottom;
        }
        QScrollBar::up-arrow:vertical {
            image: url("__UP_ARROW__");
            width: 8px;
            height: 8px;
        }
        QScrollBar::down-arrow:vertical {
            image: url("__DOWN_ARROW__");
            width: 8px;
            height: 8px;
        }
        QScrollBar:horizontal {
            background: #f1f5f9;
            height: 12px;
            margin: 0 12px 0 12px;
            border: none;
        }
        QScrollBar::handle:horizontal {
            background: #94a3b8;
            min-width: 28px;
            margin: 4px 0;
            border-radius: 2px;
        }
        QScrollBar::handle:horizontal:hover {
            background: #64748b;
            margin: 2px 0;
            border-radius: 4px;
        }
        QScrollBar::add-page:horizontal,
        QScrollBar::sub-page:horizontal {
            background: transparent;
            border: none;
            width: 0;
        }
        QScrollBar::sub-line:horizontal,
        QScrollBar::add-line:horizontal {
            background: #f1f5f9;
            border: none;
            width: 12px;
            subcontrol-origin: margin;
        }
        QScrollBar::sub-line:horizontal {
            subcontrol-position: left;
        }
        QScrollBar::add-line:horizontal {
            subcontrol-position: right;
        }
        QScrollBar::left-arrow:horizontal {
            image: url("__LEFT_ARROW__");
            width: 8px;
            height: 8px;
        }
        QScrollBar::right-arrow:horizontal {
            image: url("__RIGHT_ARROW__");
            width: 8px;
            height: 8px;
        }
    """.replace("__INPUT_UP_ARROW__", asset_url("input-arrow-up-light.svg")) \
        .replace("__INPUT_DOWN_ARROW__", asset_url("input-arrow-down-light.svg")) \
        .replace("__UP_ARROW__", asset_url("scrollbar-arrow-up-light.svg")) \
        .replace("__DOWN_ARROW__", asset_url("scrollbar-arrow-down-light.svg")) \
        .replace("__LEFT_ARROW__", asset_url("scrollbar-arrow-left-light.svg")) \
        .replace("__RIGHT_ARROW__", asset_url("scrollbar-arrow-right-light.svg"))


def dark_stylesheet() -> str:
    return """
        QWidget {
            background-color: #1f1f1f;
            color: #f8fafc;
            selection-background-color: #3b82f6;
            selection-color: #f8fafc;
        }
        QGraphicsView {
            background-color: #2b2b2b;
            border: none;
        }
        QMenuBar {
            background-color: #242424;
            color: #f8fafc;
        }
        QMenuBar::item {
            background: transparent;
            padding: 5px 10px;
        }
        QMenuBar::item:selected {
            background-color: #343434;
        }
        QMenu {
            background-color: #242424;
            color: #f8fafc;
            border: 1px solid #444444;
        }
        QMenu::item {
            padding: 5px 24px 5px 24px;
        }
        QMenu::item:selected {
            background-color: #3a3a3a;
        }
        QMenu::item:disabled {
            color: #737373;
            background-color: transparent;
        }
        QMenu::item:selected:disabled {
            color: #737373;
            background-color: transparent;
        }
        QPushButton, QToolButton {
            background-color: #2f2f2f;
            color: #f8fafc;
            border: 1px solid #4b5563;
            border-radius: 4px;
            padding: 4px 8px;
        }
        QPushButton:hover, QToolButton:hover {
            background-color: #3f3f46;
        }
        QPushButton:disabled, QToolButton:disabled {
            background-color: #262626;
            color: #737373;
            border-color: #3a3a3a;
        }
        QTreeWidget, QTableWidget, QListWidget, QLineEdit, QComboBox, QSpinBox {
            background-color: #2b2b2b;
            color: #f8fafc;
            alternate-background-color: #353535;
            border: 1px solid #444444;
            border-radius: 4px;
            min-height: 24px;
            selection-background-color: #3b82f6;
            selection-color: #f8fafc;
        }
        QLineEdit, QComboBox, QSpinBox {
            padding: 2px 8px;
        }
        QComboBox {
            padding-right: 28px;
        }
        QComboBox:hover, QSpinBox:hover, QLineEdit:hover {
            border-color: #737373;
        }
        QComboBox:focus, QSpinBox:focus, QLineEdit:focus {
            border-color: #60a5fa;
        }
        QComboBox::drop-down {
            subcontrol-origin: padding;
            subcontrol-position: top right;
            width: 24px;
            border-left: 1px solid #444444;
            border-top-right-radius: 4px;
            border-bottom-right-radius: 4px;
            background-color: #262626;
        }
        QComboBox::drop-down:hover {
            background-color: #3f3f46;
        }
        QComboBox::down-arrow {
            image: url("__INPUT_DOWN_ARROW__");
            width: 10px;
            height: 10px;
        }
        QSpinBox {
            padding-right: 28px;
        }
        QSpinBox::up-button, QSpinBox::down-button {
            subcontrol-origin: border;
            width: 24px;
            border-left: 1px solid #444444;
            background-color: #262626;
        }
        QSpinBox::up-button {
            subcontrol-position: top right;
            border-top-right-radius: 4px;
        }
        QSpinBox::down-button {
            subcontrol-position: bottom right;
            border-bottom-right-radius: 4px;
        }
        QSpinBox::up-button:hover, QSpinBox::down-button:hover {
            background-color: #3f3f46;
        }
        QSpinBox::up-arrow {
            image: url("__INPUT_UP_ARROW__");
            width: 10px;
            height: 10px;
        }
        QSpinBox::down-arrow {
            image: url("__INPUT_DOWN_ARROW__");
            width: 10px;
            height: 10px;
        }
        QComboBox QAbstractItemView {
            background-color: #2b2b2b;
            color: #f8fafc;
            border: 1px solid #444444;
            selection-background-color: #3b82f6;
            selection-color: #f8fafc;
        }
        QHeaderView::section {
            background-color: #3a3a3a;
            color: #f8fafc;
            border: 1px solid #444444;
            padding: 4px;
        }
        QSplitter::handle {
            background-color: #111827;
        }
        QStatusBar {
            background-color: #1f1f1f;
            color: #f8fafc;
        }
        QToolTip {
            background-color: #111827;
            color: #f8fafc;
            border: 1px solid #4b5563;
        }
        QScrollBar:vertical {
            background: #1f1f1f;
            width: 12px;
            margin: 12px 0 12px 0;
            border: none;
        }
        QScrollBar::handle:vertical {
            background: #737373;
            min-height: 28px;
            margin: 0 4px;
            border-radius: 2px;
        }
        QScrollBar::handle:vertical:hover {
            background: #a3a3a3;
            margin: 0 2px;
            border-radius: 4px;
        }
        QScrollBar::add-page:vertical,
        QScrollBar::sub-page:vertical {
            background: transparent;
            border: none;
            height: 0;
        }
        QScrollBar::sub-line:vertical,
        QScrollBar::add-line:vertical {
            background: #1f1f1f;
            border: none;
            height: 12px;
            subcontrol-origin: margin;
        }
        QScrollBar::sub-line:vertical {
            subcontrol-position: top;
        }
        QScrollBar::add-line:vertical {
            subcontrol-position: bottom;
        }
        QScrollBar::up-arrow:vertical {
            image: url("__UP_ARROW__");
            width: 8px;
            height: 8px;
        }
        QScrollBar::down-arrow:vertical {
            image: url("__DOWN_ARROW__");
            width: 8px;
            height: 8px;
        }
        QScrollBar:horizontal {
            background: #1f1f1f;
            height: 12px;
            margin: 0 12px 0 12px;
            border: none;
        }
        QScrollBar::handle:horizontal {
            background: #737373;
            min-width: 28px;
            margin: 4px 0;
            border-radius: 2px;
        }
        QScrollBar::handle:horizontal:hover {
            background: #a3a3a3;
            margin: 2px 0;
            border-radius: 4px;
        }
        QScrollBar::add-page:horizontal,
        QScrollBar::sub-page:horizontal {
            background: transparent;
            border: none;
            width: 0;
        }
        QScrollBar::sub-line:horizontal,
        QScrollBar::add-line:horizontal {
            background: #1f1f1f;
            border: none;
            width: 12px;
            subcontrol-origin: margin;
        }
        QScrollBar::sub-line:horizontal {
            subcontrol-position: left;
        }
        QScrollBar::add-line:horizontal {
            subcontrol-position: right;
        }
        QScrollBar::left-arrow:horizontal {
            image: url("__LEFT_ARROW__");
            width: 8px;
            height: 8px;
        }
        QScrollBar::right-arrow:horizontal {
            image: url("__RIGHT_ARROW__");
            width: 8px;
            height: 8px;
        }
    """.replace("__INPUT_UP_ARROW__", asset_url("input-arrow-up-dark.svg")) \
        .replace("__INPUT_DOWN_ARROW__", asset_url("input-arrow-down-dark.svg")) \
        .replace("__UP_ARROW__", asset_url("scrollbar-arrow-up-dark.svg")) \
        .replace("__DOWN_ARROW__", asset_url("scrollbar-arrow-down-dark.svg")) \
        .replace("__LEFT_ARROW__", asset_url("scrollbar-arrow-left-dark.svg")) \
        .replace("__RIGHT_ARROW__", asset_url("scrollbar-arrow-right-dark.svg"))