/**
 * Custom hook for managing wizard state
 *
 * Handles step navigation logic including script mode shortcuts.
 */

import { useState, useCallback } from 'react';

import type { WizardState, WizardStep } from './types';
import { initialWizardState } from './types';
import { WIZARD_STEPS } from './constants';

interface UseWizardStateReturn {
  state: WizardState;
  updateState: (updates: Partial<WizardState>) => void;
  resetState: () => void;
  isScriptMode: boolean;
  canProceed: boolean;
  goNext: () => void;
  goBack: () => void;
  getProjectData: () => ProjectCreateData;
}

/**
 * Data structure for project creation API call
 */
export interface ProjectCreateData {
  name: string;
  slug: string;
  description: string | undefined;
  autonomy_level: 'full_control' | 'milestone' | 'autonomous';
  settings: {
    complexity: string;
    client_mode: string;
    repo_url?: string;
  };
}

/**
 * Generate a URL-safe slug from a project name
 */
function generateSlug(name: string): string {
  return name
    .toLowerCase()
    .trim()
    .replace(/[^\w\s-]/g, '') // Remove special characters
    .replace(/\s+/g, '-') // Replace spaces with hyphens
    .replace(/-+/g, '-') // Replace multiple hyphens with single
    .replace(/^-+|-+$/g, ''); // Remove leading/trailing hyphens
}

export function useWizardState(): UseWizardStateReturn {
  const [state, setState] = useState<WizardState>(initialWizardState);

  const isScriptMode = state.complexity === 'script';

  const updateState = useCallback((updates: Partial<WizardState>) => {
    setState((prev) => ({ ...prev, ...updates }));
  }, []);

  const resetState = useCallback(() => {
    setState(initialWizardState);
  }, []);

  /**
   * Check if user can proceed to next step
   */
  const canProceed = (() => {
    switch (state.step) {
      case WIZARD_STEPS.BASIC_INFO:
        return state.projectName.trim().length >= 3;
      case WIZARD_STEPS.COMPLEXITY:
        return state.complexity !== null;
      case WIZARD_STEPS.CLIENT_MODE:
        return isScriptMode || state.clientMode !== null;
      case WIZARD_STEPS.AUTONOMY:
        return isScriptMode || state.autonomyLevel !== null;
      case WIZARD_STEPS.AGENT_CHAT:
        return true; // Agent chat is preview only
      case WIZARD_STEPS.REVIEW:
        return true;
      default:
        return false;
    }
  })();

  /**
   * Navigate to next step, handling script mode skip logic
   */
  const goNext = useCallback(() => {
    if (!canProceed) return;

    setState((prev) => {
      let nextStep = (prev.step + 1) as WizardStep;
      const currentIsScriptMode = prev.complexity === 'script';

      // For scripts, skip from step 2 directly to step 5 (agent chat)
      if (currentIsScriptMode && prev.step === WIZARD_STEPS.COMPLEXITY) {
        return {
          ...prev,
          step: WIZARD_STEPS.AGENT_CHAT as WizardStep,
          clientMode: 'auto',
          autonomyLevel: 'autonomous',
        };
      }

      // Don't go past review step
      if (nextStep > WIZARD_STEPS.REVIEW) {
        nextStep = WIZARD_STEPS.REVIEW as WizardStep;
      }

      return { ...prev, step: nextStep };
    });
  }, [canProceed]);

  /**
   * Navigate to previous step, handling script mode skip logic
   */
  const goBack = useCallback(() => {
    setState((prev) => {
      if (prev.step <= 1) return prev;

      let prevStep = (prev.step - 1) as WizardStep;
      const currentIsScriptMode = prev.complexity === 'script';

      // For scripts, go from step 5 back to step 2
      if (currentIsScriptMode && prev.step === WIZARD_STEPS.AGENT_CHAT) {
        prevStep = WIZARD_STEPS.COMPLEXITY as WizardStep;
      }

      return { ...prev, step: prevStep };
    });
  }, []);

  /**
   * Get data formatted for the project creation API
   */
  const getProjectData = useCallback((): ProjectCreateData => {
    const slug = generateSlug(state.projectName);

    return {
      name: state.projectName.trim(),
      slug,
      description: state.description.trim() || undefined,
      autonomy_level: state.autonomyLevel || 'milestone',
      settings: {
        complexity: state.complexity || 'medium',
        client_mode: state.clientMode || 'auto',
        ...(state.repoUrl && { repo_url: state.repoUrl }),
      },
    };
  }, [state]);

  return {
    state,
    updateState,
    resetState,
    isScriptMode,
    canProceed,
    goNext,
    goBack,
    getProjectData,
  };
}