"""Global dark theme for the GUI (Fusion style + palette + stylesheet).

Applied once at startup from ``gui.main``.  The per-widget ``setStyleSheet``
colors sprinkled through ``gui.py`` (``#999`` secondary text, ``#e06c6c`` delete
buttons, ``#14151a`` preview panels) were written for a dark background, so a
single cohesive dark theme here makes the whole UI consistent.
"""
from PySide6.QtGui import QColor, QPalette

from . import config

# Design tokens
BG = "#1e1f24"        # window background
SURFACE = "#26272e"   # cards, inputs, table headers
RAISED = "#2d2e36"    # buttons, combos, menus
BORDER = "#3a3b44"
BORDER_SOFT = "#33343d"
TEXT = "#e6e6ea"
TEXT_DIM = "#9a9ba5"
TEXT_FAINT = "#6f7079"
ACCENT = "#4a9eff"
ACCENT_HOVER = "#6bb0ff"


_STYLESHEET = f"""
QMainWindow {{
    background: {BG};
}}
QWidget {{
    color: {TEXT};
}}

/* --- Tabs --- */
QTabWidget::pane {{
    border: 1px solid {BORDER};
    border-radius: 6px;
    top: -1px;
}}
QTabBar::tab {{
    background: transparent;
    color: {TEXT_DIM};
    padding: 8px 18px;
    border: none;
    border-bottom: 2px solid transparent;
    margin-right: 2px;
}}
QTabBar::tab:hover:!selected {{
    color: {TEXT};
}}
QTabBar::tab:selected {{
    color: {TEXT};
    border-bottom: 2px solid {ACCENT};
}}

/* --- Buttons --- */
QPushButton {{
    background: {RAISED};
    border: 1px solid {BORDER};
    border-radius: 6px;
    padding: 6px 12px;
}}
QPushButton:hover {{
    background: #343640;
    border-color: {ACCENT_HOVER};
}}
QPushButton:pressed {{
    background: {SURFACE};
}}
QPushButton:disabled {{
    color: {TEXT_FAINT};
    background: {SURFACE};
    border-color: {BORDER_SOFT};
}}
QPushButton:checked {{
    background: {ACCENT};
    border-color: {ACCENT};
    color: #101116;
}}

/* --- Inputs --- */
QLineEdit, QSpinBox, QPlainTextEdit, QTextEdit {{
    background: {SURFACE};
    border: 1px solid {BORDER};
    border-radius: 6px;
    padding: 5px 8px;
    selection-background-color: {ACCENT};
    selection-color: #101116;
}}
QLineEdit:focus, QSpinBox:focus, QPlainTextEdit:focus, QTextEdit:focus {{
    border-color: {ACCENT};
}}
QLineEdit:disabled, QSpinBox:disabled {{
    color: {TEXT_FAINT};
}}

/* --- Combo boxes --- */
QComboBox {{
    background: {RAISED};
    border: 1px solid {BORDER};
    border-radius: 6px;
    padding: 4px 10px;
}}
QComboBox:hover {{
    border-color: {ACCENT_HOVER};
}}
QComboBox::drop-down {{
    border: none;
    width: 22px;
}}
QComboBox::down-arrow {{
    image: url(__CHEVRON__);
    width: 12px;
    height: 8px;
    margin-right: 6px;
}}
QComboBox QAbstractItemView {{
    background: {RAISED};
    border: 1px solid {BORDER};
    border-radius: 6px;
    selection-background-color: rgba(74, 158, 255, 0.25);
    selection-color: {TEXT};
    outline: 0;
}}

/* --- Tables --- */
QTableWidget {{
    background: transparent;
    border: none;
    gridline-color: {BORDER_SOFT};
}}
QHeaderView::section {{
    background: {SURFACE};
    color: {TEXT_DIM};
    border: none;
    border-bottom: 1px solid {BORDER};
    padding: 6px 8px;
}}
QTableWidget::item {{
    padding: 4px 6px;
}}
QTableWidget::item:selected {{
    background: rgba(74, 158, 255, 0.22);
    color: {TEXT};
}}
QTableCornerButton::section {{
    background: {SURFACE};
    border: none;
    border-bottom: 1px solid {BORDER};
}}

/* --- Cover grid / lists --- */
QListWidget {{
    background: transparent;
    border: none;
}}
QListWidget::item {{
    border-radius: 6px;
}}
QListWidget::item:hover:!selected {{
    background: rgba(255, 255, 255, 0.04);
}}
QListWidget::item:selected {{
    background: rgba(74, 158, 255, 0.22);
}}

/* --- Cards (details panels use QScrollArea) --- */
QScrollArea {{
    background: {SURFACE};
    border: none;
}}

/* --- Menus --- */
QMenu {{
    background: {RAISED};
    border: 1px solid {BORDER};
    border-radius: 6px;
    padding: 4px;
}}
QMenu::item {{
    padding: 6px 26px 6px 12px;
    border-radius: 4px;
}}
QMenu::item:selected {{
    background: rgba(74, 158, 255, 0.25);
}}
QMenu::separator {{
    height: 1px;
    background: {BORDER};
    margin: 4px 8px;
}}

/* --- Scrollbars --- */
QScrollBar:vertical {{
    background: transparent;
    width: 10px;
    margin: 0;
}}
QScrollBar::handle:vertical {{
    background: {BORDER};
    border-radius: 5px;
    min-height: 30px;
}}
QScrollBar::handle:vertical:hover {{
    background: {ACCENT};
}}
QScrollBar:horizontal {{
    background: transparent;
    height: 10px;
    margin: 0;
}}
QScrollBar::handle:horizontal {{
    background: {BORDER};
    border-radius: 5px;
    min-width: 30px;
}}
QScrollBar::handle:horizontal:hover {{
    background: {ACCENT};
}}
QScrollBar::add-line, QScrollBar::sub-line {{
    width: 0;
    height: 0;
}}
QScrollBar::add-page, QScrollBar::sub-page {{
    background: transparent;
}}

/* --- Splitter --- */
QSplitter::handle {{
    background: transparent;
}}
QSplitter::handle:horizontal {{
    width: 1px;
}}
QSplitter::handle:vertical {{
    height: 1px;
}}

/* --- Misc --- */
QToolTip {{
    background: {RAISED};
    color: {TEXT};
    border: 1px solid {BORDER};
    padding: 4px 6px;
}}
QStatusBar {{
    background: {SURFACE};
    color: {TEXT_DIM};
    border-top: 1px solid {BORDER};
}}
QProgressBar {{
    background: {SURFACE};
    border: 1px solid {BORDER};
    border-radius: 6px;
    text-align: center;
}}
QProgressBar::chunk {{
    background: {ACCENT};
    border-radius: 5px;
}}
QCheckBox {{
    spacing: 8px;
}}
QCheckBox::indicator {{
    width: 16px;
    height: 16px;
    border: 1px solid {BORDER};
    border-radius: 4px;
    background: {SURFACE};
}}
QCheckBox::indicator:checked {{
    background: {ACCENT};
    border-color: {ACCENT};
}}
QGroupBox {{
    border: 1px solid {BORDER};
    border-radius: 6px;
    margin-top: 10px;
}}
QGroupBox::title {{
    subcontrol-origin: margin;
    left: 10px;
    padding: 0 4px;
    color: {TEXT_DIM};
}}
"""


def _dark_palette():
    p = QPalette()
    p.setColor(QPalette.Window, QColor(BG))
    p.setColor(QPalette.WindowText, QColor(TEXT))
    p.setColor(QPalette.Base, QColor(SURFACE))
    p.setColor(QPalette.AlternateBase, QColor(RAISED))
    p.setColor(QPalette.ToolTipBase, QColor(RAISED))
    p.setColor(QPalette.ToolTipText, QColor(TEXT))
    p.setColor(QPalette.Text, QColor(TEXT))
    p.setColor(QPalette.Button, QColor(RAISED))
    p.setColor(QPalette.ButtonText, QColor(TEXT))
    p.setColor(QPalette.BrightText, QColor("#ff5c5c"))
    p.setColor(QPalette.Link, QColor(ACCENT))
    p.setColor(QPalette.Highlight, QColor(ACCENT))
    p.setColor(QPalette.HighlightedText, QColor("#101116"))
    p.setColor(QPalette.PlaceholderText, QColor(TEXT_FAINT))

    faint = QColor(TEXT_FAINT)
    for role in (QPalette.WindowText, QPalette.Text, QPalette.ButtonText):
        p.setColor(QPalette.Disabled, role, faint)
    return p


def apply_theme(app):
    """Apply the dark Fusion theme to ``app`` (call once before showing UI)."""
    app.setStyle("Fusion")
    app.setPalette(_dark_palette())
    chevron = str(config.resource_path("img", "chevron.png"))
    app.setStyleSheet(_STYLESHEET.replace("__CHEVRON__", chevron))