import { create } from 'zustand';
import { invoke } from '../lib/tauri';

function logError(context: string, error: unknown): void {
  if (import.meta.env.PROD) {
    console.error(`[Swap] ${context}: ${error instanceof Error ? error.name : 'Unknown'}`);
  } else {
    console.error(`[Swap] ${context}:`, error);
  }
}

export interface SwapQuote {
  tokenIn: string;
  tokenOut: string;
  amountIn: string;
  amountOut: string;
  amountOutMin: string;
  priceImpactBps: number;
  route: string[];
  estimatedGas: number;
}

export interface LiquidityPoolInfo {
  poolAddress: string;
  tokenA: string;
  tokenB: string;
  symbolA: string;
  symbolB: string;
  reserveA: string;
  reserveB: string;
  totalSupply: string;
  feeBps: number;
}

interface SwapState {
  quote: SwapQuote | null;
  pools: LiquidityPoolInfo[];
  isLoadingQuote: boolean;
  isSwapping: boolean;
  isAddingLiquidity: boolean;
  isRemovingLiquidity: boolean;
  error: string | null;

  clearError: () => void;
  getQuote: (tokenIn: string, tokenOut: string, amountIn: string, slippageBps: number) => Promise<SwapQuote>;
  executeSwap: (tokenIn: string, tokenOut: string, amountIn: string, amountOutMin: string) => Promise<string>;
  fetchPools: () => Promise<void>;
  addLiquidity: (tokenA: string, tokenB: string, amountA: string, amountB: string) => Promise<string>;
  removeLiquidity: (poolAddress: string, lpAmount: string) => Promise<string>;
}

export const useSwapStore = create<SwapState>()((set) => ({
  quote: null,
  pools: [],
  isLoadingQuote: false,
  isSwapping: false,
  isAddingLiquidity: false,
  isRemovingLiquidity: false,
  error: null,

  clearError: () => set({ error: null }),

  getQuote: async (tokenIn, tokenOut, amountIn, slippageBps) => {
    set({ isLoadingQuote: true, error: null });
    try {
      const quote = await invoke<SwapQuote>('swap_get_quote', {
        tokenIn,
        tokenOut,
        amountIn,
        slippageBps,
      });
      set({ quote, isLoadingQuote: false });
      return quote;
    } catch (error) {
      const msg = error instanceof Error ? error.message : 'Quote failed';
      logError('getQuote', error);
      set({ error: msg, isLoadingQuote: false });
      throw error;
    }
  },

  executeSwap: async (tokenIn, tokenOut, amountIn, amountOutMin) => {
    set({ isSwapping: true, error: null });
    try {
      const txHash = await invoke<string>('swap_execute', {
        tokenIn,
        tokenOut,
        amountIn,
        amountOutMin,
      });
      set({ isSwapping: false, quote: null });
      return txHash;
    } catch (error) {
      const msg = error instanceof Error ? error.message : 'Swap failed';
      logError('executeSwap', error);
      set({ error: msg, isSwapping: false });
      throw error;
    }
  },

  fetchPools: async () => {
    try {
      const pools = await invoke<LiquidityPoolInfo[]>('swap_get_pools');
      set({ pools });
    } catch (error) {
      logError('fetchPools', error);
    }
  },

  addLiquidity: async (tokenA, tokenB, amountA, amountB) => {
    set({ isAddingLiquidity: true, error: null });
    try {
      const txHash = await invoke<string>('swap_add_liquidity', {
        tokenA,
        tokenB,
        amountA,
        amountB,
      });
      set({ isAddingLiquidity: false });
      return txHash;
    } catch (error) {
      const msg = error instanceof Error ? error.message : 'Add liquidity failed';
      logError('addLiquidity', error);
      set({ error: msg, isAddingLiquidity: false });
      throw error;
    }
  },

  removeLiquidity: async (poolAddress, lpAmount) => {
    set({ isRemovingLiquidity: true, error: null });
    try {
      const txHash = await invoke<string>('swap_remove_liquidity', {
        poolAddress,
        lpAmount,
      });
      set({ isRemovingLiquidity: false });
      return txHash;
    } catch (error) {
      const msg = error instanceof Error ? error.message : 'Remove liquidity failed';
      logError('removeLiquidity', error);
      set({ error: msg, isRemovingLiquidity: false });
      throw error;
    }
  },
}));

export function formatPriceImpact(bps: number): string {
  const pct = bps / 100;
  if (pct < 0.01) return '<0.01%';
  return `${pct.toFixed(2)}%`;
}