src/static-analyzer.ts

/**
 * Static Analysis Module
 * Runs deterministic static analysis before LLM review
 * Uses enhanced regex-based checks for syntax errors
 * Injects findings into LLM prompt for context
 */

interface StaticAnalysisFinding {
  line?: number
  severity: 'error' | 'warning'
  message: string
  rule?: string
}

interface StaticAnalysisResult {
  filename: string
  findings: StaticAnalysisFinding[]
}

/**
 * Analyze Python for basic syntax issues
 */
function analyzePythonBasic(content: string): StaticAnalysisFinding[] {
  const findings: StaticAnalysisFinding[] = []
  const lines = content.split('\n')

  // Check for common Python issues
  lines.forEach((line, idx) => {
    const lineNum = idx + 1

    // Check for unmatched parentheses
    const openBrackets = (line.match(/\(/g) || []).length
    const closeBrackets = (line.match(/\)/g) || []).length
    if (openBrackets !== closeBrackets) {
      findings.push({
        line: lineNum,
        severity: 'error',
        message: 'Unmatched parentheses detected',
        rule: 'syntax-balance'
      })
    }

    // Check for unmatched braces
    const openBraces = (line.match(/\{/g) || []).length
    const closeBraces = (line.match(/\}/g) || []).length
    if (openBraces !== closeBraces) {
      findings.push({
        line: lineNum,
        severity: 'error',
        message: 'Unmatched braces detected',
        rule: 'syntax-balance'
      })
    }

    // Check for unmatched square brackets
    const openSquare = (line.match(/\[/g) || []).length
    const closeSquare = (line.match(/\]/g) || []).length
    if (openSquare !== closeSquare) {
      findings.push({
        line: lineNum,
        severity: 'error',
        message: 'Unmatched square brackets detected',
        rule: 'syntax-balance'
      })
    }
  })

  return findings
}

/**
 * Analyze JavaScript/TypeScript for basic syntax issues
 */
function analyzeJavaScriptBasic(_content: string): StaticAnalysisFinding[] {
  return []
}

function analyzeTypeScriptEnhanced(content: string): StaticAnalysisFinding[] {
  const findings: StaticAnalysisFinding[] = []
  const lines = content.split('\n')

  lines.forEach((line, idx) => {
    const lineNum = idx + 1
    const trimmed = line.trim()

    // Check for TypeScript syntax issues
    if (trimmed.includes('interface') && !trimmed.includes('{')) {
      findings.push({
        line: lineNum,
        severity: 'error',
        message: 'Interface declaration missing opening brace',
        rule: 'ts-syntax'
      })
    }

    // Check for type assertion issues
    if (trimmed.match(/<[^>]+>\s*[^=]/) && !trimmed.includes('extends')) {
      findings.push({
        line: lineNum,
        severity: 'warning',
        message: 'Potential type assertion - consider using as keyword',
        rule: 'ts-style'
      })
    }

    // Check for async/await without error handling
    if (
      trimmed.includes('await') &&
      !trimmed.includes('try') &&
      !trimmed.includes('catch') &&
      !line.includes('.catch(') &&
      !line.includes('await Promise.')
    ) {
      findings.push({
        line: lineNum,
        severity: 'warning',
        message: 'Await without error handling',
        rule: 'async-error'
      })
    }

    // Check for console.log in production code
    if (
      trimmed.includes('console.log') ||
      trimmed.includes('console.warn') ||
      trimmed.includes('console.error')
    ) {
      findings.push({
        line: lineNum,
        severity: 'warning',
        message: 'Console statement detected',
        rule: 'no-console'
      })
    }

    // Check for any type usage (warning)
    if (
      trimmed.includes(': any') ||
      trimmed.includes('any[]') ||
      trimmed.includes('any>')
    ) {
      findings.push({
        line: lineNum,
        severity: 'warning',
        message: 'Using any type reduces type safety',
        rule: 'no-any'
      })
    }
  })

  return findings
}

/**
 * Main static analysis function
 * Analyzes file content and returns findings
 */
export async function analyzeStatic(
  content: string,
  filename: string
): Promise<StaticAnalysisResult> {
  const ext = filename.split('.').pop()?.toLowerCase()
  let findings: StaticAnalysisFinding[] = []

  switch (ext) {
    case 'py':
      findings = analyzePythonBasic(content)
      break
    case 'js':
    case 'jsx':
    case 'ts':
    case 'tsx':
      findings = analyzeTypeScriptEnhanced(content)
      break
    default:
      // No static analysis for other file types
      break
  }

  return {
    filename,
    findings
  }
}

/**
 * Format static analysis findings for injection into LLM prompt
 * Bug Fix #2: Always return content so LLM knows analysis was performed
 */
export function formatStaticAnalysisFindings(
  findings: StaticAnalysisFinding[]
): string {
  if (findings.length === 0) {
    return 'Static analysis: No syntax errors or common issues detected.'
  }

  const formatted = findings
    .map(f => {
      const line = f.line ? ` line ${f.line}` : ''
      const rule = f.rule ? ` [${f.rule}]` : ''
      return `- ${f.severity.toUpperCase()}${line}${rule}: ${f.message}`
    })
    .join('\n')

  return `Static analysis detected:\n${formatted}`
}