export type ThemeId = 'dark' | 'light' | 'high-contrast' | 'soft';

export interface ThemeOption {
  id: ThemeId;
  name: string;
  subtitle: string;
  file: string;
  previewBg: string;
  previewPanel: string;
  previewAccent: string;
  previewText: string;
  isRounded: boolean;
}

export const THEME_STORAGE_KEY = 'mindsift_active_theme';

export const AVAILABLE_THEMES: ThemeOption[] = [
  {
    id: 'dark',
    name: 'MindSift Dark (Standard)',
    subtitle: 'Monochrom, dunkel & eckig (0px)',
    file: 'src/themes/theme-dark.css',
    previewBg: '#121316',
    previewPanel: '#1a1c20',
    previewAccent: '#2563eb',
    previewText: '#f4f4f5',
    isRounded: false,
  },
  {
    id: 'light',
    name: 'MindSift Light (Tagmodus)',
    subtitle: 'Helles Papier-Design & klare Kontraste',
    file: 'src/themes/theme-light.css',
    previewBg: '#f3f4f6',
    previewPanel: '#ffffff',
    previewAccent: '#2563eb',
    previewText: '#111827',
    isRounded: false,
  },
  {
    id: 'high-contrast',
    name: 'High Contrast (Scharf)',
    subtitle: 'Tiefschwarz (#000) & weiße Konturen',
    file: 'src/themes/theme-high-contrast.css',
    previewBg: '#000000',
    previewPanel: '#09090b',
    previewAccent: '#38bdf8',
    previewText: '#ffffff',
    isRounded: false,
  },
  {
    id: 'soft',
    name: 'Soft Slate (Abgerundet)',
    subtitle: 'Schiefer-Blau mit weichen Radien (10px)',
    file: 'src/themes/theme-soft.css',
    previewBg: '#0f172a',
    previewPanel: '#1e293b',
    previewAccent: '#3b82f6',
    previewText: '#f8fafc',
    isRounded: true,
  },
];

export function getActiveTheme(): ThemeId {
  try {
    const saved = localStorage.getItem(THEME_STORAGE_KEY) as ThemeId | null;
    if (saved && AVAILABLE_THEMES.some((t) => t.id === saved)) {
      return saved;
    }
  } catch {
    // ignore
  }
  return 'dark';
}

export function setActiveTheme(themeId: ThemeId): void {
  try {
    localStorage.setItem(THEME_STORAGE_KEY, themeId);
  } catch {
    // ignore
  }
  if (typeof document !== 'undefined') {
    document.documentElement.setAttribute('data-theme', themeId);
  }
}

export function initThemeOnBoot(): ThemeId {
  const active = getActiveTheme();
  if (typeof document !== 'undefined') {
    document.documentElement.setAttribute('data-theme', active);
  }
  return active;
}