import { describe, test, expect, beforeEach, vi } from 'vitest';
import {
  getSavedSessions,
  saveSession,
  deleteSession,
  formatSessionAsMarkdown,
  downloadFile
} from '../services/sessionStorage';
import type { Scenario, Message, AnalysisResult } from '../types';

describe('Session Storage & Export Service', () => {
  const mockStorage: Record<string, string> = {};

  const mockScenario: Scenario = {
    id: 'test-scenario-1',
    title: 'Workplace Disagreement',
    description: 'Resolving friction with a manager',
    category: 'Workplace',
    difficulty: 'Intermediate',
    systemInstruction: 'INTERNAL CBT LOGIC: React with skepticism.',
    initialMessage: 'Why was this project late?',
    cbtFocus: ['All-or-Nothing Thinking', 'Mind Reading'],
    characterName: 'Director Vance'
  };

  const mockMessages: Message[] = [
    {
      id: 'm1',
      role: 'model',
      text: 'Why was this project late?',
      timestamp: new Date()
    },
    {
      id: 'm2',
      role: 'user',
      text: 'We encountered unexpected API downtime, but delivered within scope.',
      timestamp: new Date()
    }
  ];

  const mockAnalysis: AnalysisResult = {
    analysis: {
      distortions: ['Mind Reading'],
      isAdaptive: true,
      evidence: 'User acknowledged the delay factually without catastrophic self-blame.'
    },
    rating: {
      score: 4,
      reason: 'Strong boundary maintenance and objective attribution.'
    },
    suggestions: {
      alternativeThought: 'Delays happen due to technical constraints; focus on resolution.',
      behavioralStep: 'Send an updated post-mortem dashboard to stakeholders.'
    }
  };

  beforeEach(() => {
    for (const key in mockStorage) {
      delete mockStorage[key];
    }

    vi.stubGlobal('localStorage', {
      getItem: (key: string) => mockStorage[key] || null,
      setItem: (key: string, val: string) => {
        mockStorage[key] = val;
      },
      removeItem: (key: string) => {
        delete mockStorage[key];
      },
      clear: () => {
        for (const key in mockStorage) {
          delete mockStorage[key];
        }
      }
    });
  });

  test('getSavedSessions returns empty array when storage is empty', () => {
    expect(getSavedSessions()).toEqual([]);
  });

  test('getSavedSessions handles corrupted JSON gracefully', () => {
    mockStorage['cognitive-clarity-saved-sessions'] = 'INVALID_JSON_CORRUPTED';
    const sessions = getSavedSessions();
    expect(sessions).toEqual([]);
  });

  test('saveSession stores new session and retrieves it', () => {
    const saved = saveSession(mockScenario, 'text', mockMessages, mockAnalysis);
    expect(saved.scenarioId).toBe(mockScenario.id);
    expect(saved.scenarioTitle).toBe(mockScenario.title);
    expect(saved.mode).toBe('text');
    expect(saved.messages.length).toBe(2);
    expect(saved.finalReport?.rating.score).toBe(4);

    const all = getSavedSessions();
    expect(all.length).toBe(1);
    expect(all[0].id).toBe(saved.id);
  });

  test('saveSession caps history at 50 sessions', () => {
    for (let i = 0; i < 55; i++) {
      saveSession(
        { ...mockScenario, id: `scenario-${i}` },
        'text',
        mockMessages
      );
    }

    const all = getSavedSessions();
    expect(all.length).toBe(50);
  });

  test('deleteSession removes specific session by id', () => {
    const s1 = saveSession(mockScenario, 'text', mockMessages);
    const s2 = saveSession({ ...mockScenario, id: 's2', title: 'Second' }, 'voice', mockMessages);

    expect(getSavedSessions().length).toBe(2);

    deleteSession(s1.id);
    const remaining = getSavedSessions();
    expect(remaining.length).toBe(1);
    expect(remaining[0].id).toBe(s2.id);
  });

  test('formatSessionAsMarkdown generates structured markdown report with all sections', () => {
    const md = formatSessionAsMarkdown('Workplace Disagreement', mockAnalysis, mockMessages);

    expect(md).toContain('# Cognitive Clarity — Clinical CBT Session Report');
    expect(md).toContain('**Scenario:** Workplace Disagreement');
    expect(md).toContain('✅ Adaptive Growth Observed');
    expect(md).toContain('**Mastery Rating:** 4 / 5');
    expect(md).toContain('- Mind Reading');
    expect(md).toContain('User acknowledged the delay factually');
    expect(md).toContain('Delays happen due to technical constraints');
    expect(md).toContain('## 3. Session Transcript');
    expect(md).toContain('**[AI Partner]**: Why was this project late?');
    expect(md).toContain('**[You]**: We encountered unexpected API downtime');
  });

  test('downloadFile creates object URL and triggers anchor click in DOM', () => {
    let clicked = false;
    let appended = false;
    let removed = false;
    let revokedUrl = '';

    const mockAnchor = {
      href: '',
      download: '',
      click: () => {
        clicked = true;
      }
    };

    vi.stubGlobal('URL', {
      createObjectURL: () => 'blob:mock-url-123',
      revokeObjectURL: (url: string) => {
        revokedUrl = url;
      }
    });

    vi.stubGlobal('document', {
      createElement: () => mockAnchor,
      body: {
        appendChild: () => {
          appended = true;
        },
        removeChild: () => {
          removed = true;
        }
      }
    });

    downloadFile('# Report', 'report.md', 'text/markdown');

    expect(mockAnchor.download).toBe('report.md');
    expect(mockAnchor.href).toBe('blob:mock-url-123');
    expect(clicked).toBe(true);
    expect(appended).toBe(true);
    expect(removed).toBe(true);
    expect(revokedUrl).toBe('blob:mock-url-123');
  });
});