import { describe, it, expect } from 'vitest';
import {
  validateSparqlQuery,
  formatValidationResult,
  isSafeQuery,
  type ValidationResult,
} from '../../src/lib/sparql/validator';

describe('SPARQL Validator', () => {
  describe('validateSparqlQuery', () => {
    it('should validate correct SELECT query', () => {
      const query = `
        PREFIX schema: <http://schema.org/>
        
        SELECT ?museum ?name WHERE {
          ?museum a schema:Museum .
          ?museum schema:name ?name .
        }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.isValid).toBe(true);
      expect(result.errors).toHaveLength(0);
    });
    
    it('should reject empty query', () => {
      const result = validateSparqlQuery('');
      
      expect(result.isValid).toBe(false);
      expect(result.errors.length).toBeGreaterThan(0);
      expect(result.errors[0].message).toContain('empty');
    });
    
    it('should reject query without query type', () => {
      const query = `
        PREFIX schema: <http://schema.org/>
        WHERE {
          ?museum a schema:Museum .
        }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.isValid).toBe(false);
      expect(result.errors.some(e => e.message.includes('SELECT'))).toBe(true);
    });
    
    it('should reject SELECT query without WHERE clause', () => {
      const query = `
        PREFIX schema: <http://schema.org/>
        SELECT ?museum
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.isValid).toBe(false);
      expect(result.errors.some(e => e.message.includes('WHERE'))).toBe(true);
    });
    
    it('should detect unbalanced braces', () => {
      const query = `
        SELECT ?museum WHERE {
          ?museum a schema:Museum .
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.isValid).toBe(false);
      expect(result.errors.some(e => e.message.includes('braces'))).toBe(true);
    });
    
    it('should warn about unbalanced parentheses', () => {
      const query = `
        SELECT ?museum WHERE {
          ?museum a schema:Museum .
          FILTER(?year > 2000
        }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.warnings.some(w => w.message.includes('parentheses'))).toBe(true);
    });
    
    it('should warn about undeclared prefixes', () => {
      const query = `
        SELECT ?museum WHERE {
          ?museum a schema:Museum .
        }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.warnings.some(w => w.message.includes('schema'))).toBe(true);
      expect(result.warnings.some(w => w.message.includes('not declared'))).toBe(true);
    });
    
    it('should warn about unused prefixes', () => {
      const query = `
        PREFIX schema: <http://schema.org/>
        PREFIX unused: <http://example.org/>
        
        SELECT ?museum WHERE {
          ?museum a schema:Museum .
        }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.warnings.some(w => w.message.includes('unused'))).toBe(true);
    });
    
    it('should accept ASK queries without WHERE', () => {
      const query = 'ASK { ?s ?p ?o }';
      
      const result = validateSparqlQuery(query);
      
      // ASK queries don't require WHERE clause
      expect(result.isValid).toBe(true);
    });
    
    it('should accept CONSTRUCT queries', () => {
      const query = `
        CONSTRUCT { ?s ?p ?o }
        WHERE { ?s ?p ?o }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.isValid).toBe(true);
    });
    
    it('should accept DESCRIBE queries', () => {
      const query = 'DESCRIBE <http://example.org/museum1>';
      
      const result = validateSparqlQuery(query);
      
      expect(result.isValid).toBe(true);
    });
    
    it('should warn about SELECT variables not in WHERE', () => {
      const query = `
        PREFIX schema: <http://schema.org/>
        
        SELECT ?museum ?name ?description WHERE {
          ?museum a schema:Museum .
          ?museum schema:name ?name .
        }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.warnings.some(w => w.message.includes('description'))).toBe(true);
    });
    
    it('should handle SELECT * correctly', () => {
      const query = `
        PREFIX schema: <http://schema.org/>
        
        SELECT * WHERE {
          ?museum a schema:Museum .
        }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.isValid).toBe(true);
    });
    
    it('should warn about == in FILTER (should be =)', () => {
      const query = `
        PREFIX schema: <http://schema.org/>
        
        SELECT ?museum WHERE {
          ?museum a schema:Museum .
          FILTER(?year == 2000)
        }
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.warnings.some(w => w.message.includes('single ='))).toBe(true);
    });
    
    it('should validate complex query with OPTIONAL and FILTER', () => {
      const query = `
        PREFIX schema: <http://schema.org/>
        PREFIX owl: <http://www.w3.org/2002/07/owl#>
        
        SELECT ?museum ?name ?wikidata WHERE {
          ?museum a schema:Museum .
          ?museum schema:name ?name .
          
          OPTIONAL {
            ?museum owl:sameAs ?wikidataURI .
            FILTER(STRSTARTS(STR(?wikidataURI), "http://www.wikidata.org/"))
            BIND(STRAFTER(STR(?wikidataURI), "http://www.wikidata.org/entity/") AS ?wikidata)
          }
        }
        ORDER BY ?name
        LIMIT 100
      `;
      
      const result = validateSparqlQuery(query);
      
      expect(result.isValid).toBe(true);
    });
  });
  
  describe('formatValidationResult', () => {
    it('should format valid result', () => {
      const result: ValidationResult = {
        isValid: true,
        errors: [],
        warnings: [],
      };
      
      const formatted = formatValidationResult(result);
      
      expect(formatted).toContain('✓');
      expect(formatted).toContain('Valid');
    });
    
    it('should format result with errors', () => {
      const result: ValidationResult = {
        isValid: false,
        errors: [
          { line: 1, column: 1, message: 'Missing WHERE clause', severity: 'error' },
        ],
        warnings: [],
      };
      
      const formatted = formatValidationResult(result);
      
      expect(formatted).toContain('❌');
      expect(formatted).toContain('error');
      expect(formatted).toContain('Missing WHERE clause');
    });
    
    it('should format result with warnings', () => {
      const result: ValidationResult = {
        isValid: true,
        errors: [],
        warnings: [
          { line: 1, column: 1, message: 'Unused prefix', severity: 'warning' },
        ],
      };
      
      const formatted = formatValidationResult(result);
      
      expect(formatted).toContain('⚠️');
      expect(formatted).toContain('warning');
      expect(formatted).toContain('Unused prefix');
    });
    
    it('should format result with both errors and warnings', () => {
      const result: ValidationResult = {
        isValid: false,
        errors: [
          { line: 1, column: 1, message: 'Syntax error', severity: 'error' },
        ],
        warnings: [
          { line: 2, column: 1, message: 'Unused variable', severity: 'warning' },
        ],
      };
      
      const formatted = formatValidationResult(result);
      
      expect(formatted).toContain('❌');
      expect(formatted).toContain('⚠️');
      expect(formatted).toContain('Syntax error');
      expect(formatted).toContain('Unused variable');
    });
  });
  
  describe('isSafeQuery', () => {
    it('should accept SELECT queries', () => {
      const query = 'SELECT ?s WHERE { ?s ?p ?o }';
      
      expect(isSafeQuery(query)).toBe(true);
    });
    
    it('should accept CONSTRUCT queries', () => {
      const query = 'CONSTRUCT { ?s ?p ?o } WHERE { ?s ?p ?o }';
      
      expect(isSafeQuery(query)).toBe(true);
    });
    
    it('should reject DELETE queries', () => {
      const query = 'DELETE { ?s ?p ?o } WHERE { ?s ?p ?o }';
      
      expect(isSafeQuery(query)).toBe(false);
    });
    
    it('should reject INSERT queries', () => {
      const query = 'INSERT { ?s ?p ?o } WHERE { ?s ?p ?o }';
      
      expect(isSafeQuery(query)).toBe(false);
    });
    
    it('should reject DROP queries', () => {
      const query = 'DROP GRAPH <http://example.org/graph>';
      
      expect(isSafeQuery(query)).toBe(false);
    });
    
    it('should reject CLEAR queries', () => {
      const query = 'CLEAR GRAPH <http://example.org/graph>';
      
      expect(isSafeQuery(query)).toBe(false);
    });
    
    it('should reject UPDATE queries', () => {
      const query = 'UPDATE { ?s schema:name "New Name" } WHERE { ?s ?p ?o }';
      
      expect(isSafeQuery(query)).toBe(false);
    });
    
    it('should reject LOAD queries', () => {
      const query = 'LOAD <http://example.org/data.ttl>';
      
      expect(isSafeQuery(query)).toBe(false);
    });
  });
});