import { useState, useEffect, useCallback } from 'react'

export type ThemeId = 'twitter' | 'claude' | 'neo-brutalism' | 'retro-arcade' | 'aurora' | 'business'

export interface ThemeOption {
  id: ThemeId
  name: string
  description: string
  previewColors: {
    primary: string
    background: string
    accent: string
  }
}

export const THEMES: ThemeOption[] = [
  {
    id: 'twitter',
    name: 'Twitter',
    description: 'Clean and modern blue design',
    previewColors: { primary: '#4a9eff', background: '#ffffff', accent: '#e8f4ff' }
  },
  {
    id: 'claude',
    name: 'Claude',
    description: 'Warm beige tones with orange accents',
    previewColors: { primary: '#c75b2a', background: '#faf6f0', accent: '#f5ede4' }
  },
  {
    id: 'neo-brutalism',
    name: 'Neo Brutalism',
    description: 'Bold colors with hard shadows',
    previewColors: { primary: '#ff4d00', background: '#ffffff', accent: '#ffeb00' }
  },
  {
    id: 'retro-arcade',
    name: 'Retro Arcade',
    description: 'Vibrant pink and teal pixel vibes',
    previewColors: { primary: '#e8457c', background: '#f0e6d3', accent: '#4eb8a5' }
  },
  {
    id: 'aurora',
    name: 'Aurora',
    description: 'Deep violet and teal, like northern lights',
    previewColors: { primary: '#8b5cf6', background: '#faf8ff', accent: '#2dd4bf' }
  },
  {
    id: 'business',
    name: 'Business',
    description: 'Deep navy (#000e4e) and gray monochrome',
    previewColors: { primary: '#000e4e', background: '#eaecef', accent: '#6b7280' }
  }
]

const THEME_STORAGE_KEY = 'autocoder-theme'
const DARK_MODE_STORAGE_KEY = 'autocoder-dark-mode'

function getThemeClass(themeId: ThemeId): string {
  switch (themeId) {
    case 'twitter':
      return '' // Default, no class needed
    case 'claude':
      return 'theme-claude'
    case 'neo-brutalism':
      return 'theme-neo-brutalism'
    case 'retro-arcade':
      return 'theme-retro-arcade'
    case 'aurora':
      return 'theme-aurora'
    case 'business':
      return 'theme-business'
    default:
      return ''
  }
}

export function useTheme() {
  const [theme, setThemeState] = useState<ThemeId>(() => {
    try {
      const stored = localStorage.getItem(THEME_STORAGE_KEY)
      if (stored === 'twitter' || stored === 'claude' || stored === 'neo-brutalism' || stored === 'retro-arcade' || stored === 'aurora' || stored === 'business') {
        return stored
      }
    } catch {
      // localStorage not available
    }
    return 'twitter'
  })

  const [darkMode, setDarkModeState] = useState(() => {
    try {
      return localStorage.getItem(DARK_MODE_STORAGE_KEY) === 'true'
    } catch {
      return false
    }
  })

  // Apply theme and dark mode classes to document
  useEffect(() => {
    const root = document.documentElement

    // Remove all theme classes
    root.classList.remove('theme-claude', 'theme-neo-brutalism', 'theme-retro-arcade', 'theme-aurora', 'theme-business')

    // Add current theme class (if not twitter/default)
    const themeClass = getThemeClass(theme)
    if (themeClass) {
      root.classList.add(themeClass)
    }

    // Handle dark mode
    if (darkMode) {
      root.classList.add('dark')
    } else {
      root.classList.remove('dark')
    }

    // Persist to localStorage
    try {
      localStorage.setItem(THEME_STORAGE_KEY, theme)
      localStorage.setItem(DARK_MODE_STORAGE_KEY, String(darkMode))
    } catch {
      // localStorage not available
    }
  }, [theme, darkMode])

  const setTheme = useCallback((newTheme: ThemeId) => {
    setThemeState(newTheme)
  }, [])

  const setDarkMode = useCallback((enabled: boolean) => {
    setDarkModeState(enabled)
  }, [])

  const toggleDarkMode = useCallback(() => {
    setDarkModeState(prev => !prev)
  }, [])

  return {
    theme,
    setTheme,
    darkMode,
    setDarkMode,
    toggleDarkMode,
    themes: THEMES,
    currentTheme: THEMES.find(t => t.id === theme) ?? THEMES[0]
  }
}