oh-my-opencode/src/shared/pattern-matcher.ts

import type { ClaudeHooksConfig, HookMatcher } from "../hooks/claude-code-hooks/types"

/**
 * Escape all regex special characters EXCEPT asterisk (*).
 * Asterisk is preserved for glob-to-regex conversion.
 */
function escapeRegexExceptAsterisk(str: string): string {
  // Escape all regex special chars except * (which we convert to .* for glob matching)
  return str.replace(/[.+?^${}()|[\]\\]/g, "\\$&")
}

const regexCache = new Map<string, RegExp>()

export function matchesToolMatcher(toolName: string, matcher: string): boolean {
  if (!matcher) {
    return true
  }
  const patterns = matcher.split("|").map((p) => p.trim())
  return patterns.some((p) => {
    if (p.includes("*")) {
      // First escape regex special chars (except *), then convert * to .*
      let regex = regexCache.get(p)
      if (!regex) {
        const escaped = escapeRegexExceptAsterisk(p)
        regex = new RegExp(`^${escaped.replace(/\*/g, ".*")}$`, "i")
        regexCache.set(p, regex)
      }
      return regex.test(toolName)
    }
    return p.toLowerCase() === toolName.toLowerCase()
  })
}

export function findMatchingHooks(
  config: ClaudeHooksConfig,
  eventName: keyof ClaudeHooksConfig,
  toolName?: string
): HookMatcher[] {
  const hookMatchers = config[eventName]
  if (!hookMatchers) return []

  return hookMatchers.filter((hookMatcher) => {
    if (!toolName) return true
    return matchesToolMatcher(toolName, hookMatcher.matcher)
  })
}