import { create } from 'zustand'
import { immer } from 'zustand/middleware/immer'
import { devtools } from 'zustand/middleware'

interface EditorState {
  // Current state
  image: File | null
  processedImage: string | null
  mask: string | null
  background: string | null
  isProcessing: boolean
  zoom: number
  tool: 'select' | 'brush' | 'eraser' | 'wand' | null
  
  // History
  history: Array<{
    processedImage: string | null
    mask: string | null
    background: string | null
  }>
  historyIndex: number
  
  // Settings
  brushSize: number
  brushHardness: number
  tolerance: number
  feather: number
  edgeRefinement: number
  
  // Actions
  setImage: (image: File | null) => void
  setProcessedImage: (image: string | null) => void
  setMask: (mask: string | null) => void
  setBackground: (background: string | null) => void
  setIsProcessing: (processing: boolean) => void
  setZoom: (zoom: number) => void
  setTool: (tool: EditorState['tool']) => void
  
  // History actions
  saveToHistory: () => void
  undo: () => void
  redo: () => void
  canUndo: boolean
  canRedo: boolean
  
  // Settings actions
  setBrushSize: (size: number) => void
  setBrushHardness: (hardness: number) => void
  setTolerance: (tolerance: number) => void
  setFeather: (feather: number) => void
  setEdgeRefinement: (refinement: number) => void
  
  // Utils
  reset: () => void
  exportImage: (format: 'png' | 'jpeg' | 'webp', quality?: number) => Promise<Blob>
}

const initialState = {
  image: null,
  processedImage: null,
  mask: null,
  background: null,
  isProcessing: false,
  zoom: 100,
  tool: null,
  history: [],
  historyIndex: -1,
  brushSize: 20,
  brushHardness: 80,
  tolerance: 20,
  feather: 2,
  edgeRefinement: 50,
}

export const useEditorStore = create<EditorState>()(
  devtools(
    immer((set, get) => ({
      ...initialState,
      
      setImage: (image) =>
        set((state) => {
          state.image = image
          if (!image) {
            state.processedImage = null
            state.mask = null
            state.background = null
            state.history = []
            state.historyIndex = -1
          }
        }),
      
      setProcessedImage: (image) =>
        set((state) => {
          state.processedImage = image
        }),
      
      setMask: (mask) =>
        set((state) => {
          state.mask = mask
        }),
      
      setBackground: (background) =>
        set((state) => {
          state.background = background
          get().saveToHistory()
        }),
      
      setIsProcessing: (processing) =>
        set((state) => {
          state.isProcessing = processing
        }),
      
      setZoom: (zoom) =>
        set((state) => {
          state.zoom = Math.max(10, Math.min(500, zoom))
        }),
      
      setTool: (tool) =>
        set((state) => {
          state.tool = tool
        }),
      
      saveToHistory: () =>
        set((state) => {
          const { processedImage, mask, background } = state
          const historyEntry = { processedImage, mask, background }
          
          // Remove any history after current index
          state.history = state.history.slice(0, state.historyIndex + 1)
          
          // Add new entry
          state.history.push(historyEntry)
          state.historyIndex++
          
          // Limit history to 50 entries
          if (state.history.length > 50) {
            state.history.shift()
            state.historyIndex--
          }
        }),
      
      undo: () =>
        set((state) => {
          if (state.historyIndex > 0) {
            state.historyIndex--
            const entry = state.history[state.historyIndex]
            state.processedImage = entry.processedImage
            state.mask = entry.mask
            state.background = entry.background
          }
        }),
      
      redo: () =>
        set((state) => {
          if (state.historyIndex < state.history.length - 1) {
            state.historyIndex++
            const entry = state.history[state.historyIndex]
            state.processedImage = entry.processedImage
            state.mask = entry.mask
            state.background = entry.background
          }
        }),
      
      get canUndo() {
        return get().historyIndex > 0
      },
      
      get canRedo() {
        return get().historyIndex < get().history.length - 1
      },
      
      setBrushSize: (size) =>
        set((state) => {
          state.brushSize = size
        }),
      
      setBrushHardness: (hardness) =>
        set((state) => {
          state.brushHardness = hardness
        }),
      
      setTolerance: (tolerance) =>
        set((state) => {
          state.tolerance = tolerance
        }),
      
      setFeather: (feather) =>
        set((state) => {
          state.feather = feather
        }),
      
      setEdgeRefinement: (refinement) =>
        set((state) => {
          state.edgeRefinement = refinement
        }),
      
      reset: () =>
        set(() => initialState),
      
      exportImage: async (format, quality = 0.95) => {
        const { processedImage, background } = get()
        if (!processedImage) throw new Error('No image to export')
        
        // Create canvas and composite image with background
        const canvas = document.createElement('canvas')
        const ctx = canvas.getContext('2d')
        if (!ctx) throw new Error('Failed to create canvas context')
        
        return new Promise<Blob>((resolve, reject) => {
          const img = new Image()
          img.onload = () => {
            canvas.width = img.width
            canvas.height = img.height
            
            // Draw background if present
            if (background) {
              if (background.startsWith('#')) {
                ctx.fillStyle = background
                ctx.fillRect(0, 0, canvas.width, canvas.height)
              } else if (background.startsWith('linear-gradient')) {
                // Handle image backgrounds
                const bgImg = new Image()
                bgImg.onload = () => {
                  ctx.drawImage(bgImg, 0, 0, canvas.width, canvas.height)
                  ctx.drawImage(img, 0, 0)
                  canvas.toBlob(
                    (blob) => {
                      if (blob) resolve(blob)
                      else reject(new Error('Failed to export image'))
                    },
                    `image/${format}`,
                    quality
                  )
                }
                bgImg.src = background
                return
              }
            }
            
            // Draw the processed image
            ctx.drawImage(img, 0, 0)
            
            canvas.toBlob(
              (blob) => {
                if (blob) resolve(blob)
                else reject(new Error('Failed to export image'))
              },
              `image/${format}`,
              quality
            )
          }
          img.onerror = () => reject(new Error('Failed to load image'))
          img.src = processedImage
        })
      },
    }))
  )
) gradient backgrounds
                const gradient = ctx.createLinearGradient(0, 0, canvas.width, canvas.height)
                gradient.addColorStop(0, '#667eea')
                gradient.addColorStop(1, '#764ba2')
                ctx.fillStyle = gradient
                ctx.fillRect(0, 0, canvas.width, canvas.height)
              } else {
                // Handle