import type { StepType, StepStatus } from '../types';

// 流程步骤配置
export interface StepConfig {
  type: StepType;
  name: string;
  icon: string;
  description: string;
  required: boolean;
  allowSkip: boolean;
  validate?: (data: any) => boolean | string;
  onComplete?: (data: any) => void;
  onEnter?: (data: any) => void;
}

// 流程引擎配置
export interface ProcessEngineConfig {
  steps: StepConfig[];
  allowParallel: boolean;
  autoAdvance: boolean;
  requireAllCompleted: boolean;
}

// 流程状态
export interface ProcessState {
  currentStepIndex: number;
  completedSteps: Set<string>;
  skippedSteps: Set<string>;
  stepData: Record<string, any>;
  isComplete: boolean;
}

// 默认步骤顺序
export const DEFAULT_STEP_ORDER: StepType[] = [
  'confirm',
  'yarn_purchase',
  'dyeing',
  'machine_start',
  'fabric_warehouse',
];

// 步骤名称映射
export const STEP_NAMES: Record<StepType, string> = {
  confirm: '确认计划',
  yarn_purchase: '采购纱线',
  dyeing: '染纱',
  machine_start: '上机生产',
  fabric_warehouse: '坯布生产',
};

// 步骤图标映射
export const STEP_ICONS: Record<StepType, string> = {
  confirm: 'CheckCircle',
  yarn_purchase: 'Package',
  dyeing: 'Droplet',
  machine_start: 'Settings',
  fabric_warehouse: 'Warehouse',
};

// 流程引擎类
export class ProcessEngine {
  private config: ProcessEngineConfig;
  private state: ProcessState;
  private listeners: Set<(state: ProcessState) => void> = new Set();

  constructor(config: ProcessEngineConfig) {
    this.config = config;
    this.state = {
      currentStepIndex: 0,
      completedSteps: new Set(),
      skippedSteps: new Set(),
      stepData: {},
      isComplete: false,
    };
  }

  // 获取当前步骤
  getCurrentStep(): StepConfig | null {
    return this.config.steps[this.state.currentStepIndex] || null;
  }

  // 获取当前步骤索引
  getCurrentStepIndex(): number {
    return this.state.currentStepIndex;
  }

  // 获取步骤状态
  getStepStatus(stepType: StepType): StepStatus {
    if (this.state.completedSteps.has(stepType)) {
      return 'completed';
    }
    const stepIndex = this.config.steps.findIndex((s) => s.type === stepType);
    if (stepIndex === this.state.currentStepIndex) {
      return 'active';
    }
    return 'pending';
  }

  // 获取所有步骤
  getSteps(): StepConfig[] {
    return this.config.steps;
  }

  // 获取流程状态
  getState(): ProcessState {
    return { ...this.state };
  }

  // 检查是否可以进入下一步
  canAdvance(): boolean {
    const currentStep = this.getCurrentStep();
    if (!currentStep) return false;

    // 如果当前步骤已完成或允许跳过
    if (
      this.state.completedSteps.has(currentStep.type) ||
      this.state.skippedSteps.has(currentStep.type)
    ) {
      return true;
    }

    // 检查验证
    if (currentStep.validate) {
      const data = this.state.stepData[currentStep.type];
      const result = currentStep.validate(data);
      return result === true;
    }

    return !currentStep.required;
  }

  // 进入下一步
  advance(): boolean {
    if (!this.canAdvance()) return false;

    const currentStep = this.getCurrentStep();
    if (currentStep?.onComplete) {
      currentStep.onComplete(this.state.stepData[currentStep.type]);
    }

    if (this.state.currentStepIndex < this.config.steps.length - 1) {
      this.state.currentStepIndex++;
      const nextStep = this.getCurrentStep();
      if (nextStep?.onEnter) {
        nextStep.onEnter(this.state.stepData[nextStep.type]);
      }
    } else {
      this.state.isComplete = true;
    }

    this.notifyListeners();
    return true;
  }

  // 跳转到指定步骤
  jumpToStep(stepType: StepType): boolean {
    const stepIndex = this.config.steps.findIndex((s) => s.type === stepType);
    if (stepIndex === -1) return false;

    // 检查是否可以跳转（只能跳转到已完成步骤的下一步）
    if (!this.config.allowParallel) {
      for (let i = 0; i < stepIndex; i++) {
        const step = this.config.steps[i];
        if (
          step.required &&
          !this.state.completedSteps.has(step.type) &&
          !this.state.skippedSteps.has(step.type)
        ) {
          return false;
        }
      }
    }

    this.state.currentStepIndex = stepIndex;
    const step = this.getCurrentStep();
    if (step?.onEnter) {
      step.onEnter(this.state.stepData[step.type]);
    }

    this.notifyListeners();
    return true;
  }

  // 完成当前步骤
  completeStep(data?: any): boolean {
    const currentStep = this.getCurrentStep();
    if (!currentStep) return false;

    // 验证数据
    if (currentStep.validate && data !== undefined) {
      const result = currentStep.validate(data);
      if (result !== true) {
        return false;
      }
    }

    this.state.completedSteps.add(currentStep.type);
    if (data !== undefined) {
      this.state.stepData[currentStep.type] = data;
    }

    if (currentStep.onComplete) {
      currentStep.onComplete(data);
    }

    if (this.config.autoAdvance) {
      this.advance();
    }

    this.notifyListeners();
    return true;
  }

  // 跳过当前步骤
  skipStep(): boolean {
    const currentStep = this.getCurrentStep();
    if (!currentStep || !currentStep.allowSkip) return false;

    this.state.skippedSteps.add(currentStep.type);
    this.advance();
    this.notifyListeners();
    return true;
  }

  // 设置步骤数据
  setStepData(stepType: StepType, data: any): void {
    this.state.stepData[stepType] = data;
    this.notifyListeners();
  }

  // 获取步骤数据
  getStepData(stepType: StepType): any {
    return this.state.stepData[stepType];
  }

  // 重置流程
  reset(): void {
    this.state = {
      currentStepIndex: 0,
      completedSteps: new Set(),
      skippedSteps: new Set(),
      stepData: {},
      isComplete: false,
    };
    this.notifyListeners();
  }

  // 订阅状态变化
  subscribe(listener: (state: ProcessState) => void): () => void {
    this.listeners.add(listener);
    return () => {
      this.listeners.delete(listener);
    };
  }

  // 通知监听器
  private notifyListeners(): void {
    this.listeners.forEach((listener) => listener(this.getState()));
  }
}

// 创建默认流程引擎
export function createDefaultProcessEngine(
  customSteps?: Partial<StepConfig>[]
): ProcessEngine {
  const defaultSteps: StepConfig[] = DEFAULT_STEP_ORDER.map((type) => ({
    type,
    name: STEP_NAMES[type],
    icon: STEP_ICONS[type],
    description: '',
    required: true,
    allowSkip: false,
    ...(customSteps?.find((s) => s.type === type) || {}),
  }));

  return new ProcessEngine({
    steps: defaultSteps,
    allowParallel: false,
    autoAdvance: false,
    requireAllCompleted: true,
  });
}

// React Hook 封装
import { useState, useEffect, useCallback } from 'react';

export function useProcessEngine(engine: ProcessEngine) {
  const [state, setState] = useState<ProcessState>(engine.getState());

  useEffect(() => {
    return engine.subscribe((newState) => {
      setState(newState);
    });
  }, [engine]);

  const advance = useCallback(() => engine.advance(), [engine]);
  const completeStep = useCallback(
    (data?: any) => engine.completeStep(data),
    [engine]
  );
  const skipStep = useCallback(() => engine.skipStep(), [engine]);
  const jumpToStep = useCallback(
    (stepType: StepType) => engine.jumpToStep(stepType),
    [engine]
  );
  const setStepData = useCallback(
    (stepType: StepType, data: any) => engine.setStepData(stepType, data),
    [engine]
  );
  const reset = useCallback(() => engine.reset(), [engine]);

  return {
    state,
    currentStep: engine.getCurrentStep(),
    currentStepIndex: engine.getCurrentStepIndex(),
    steps: engine.getSteps(),
    getStepStatus: engine.getStepStatus.bind(engine),
    canAdvance: engine.canAdvance.bind(engine),
    advance,
    completeStep,
    skipStep,
    jumpToStep,
    setStepData,
    reset,
  };
}