import { findHiddenUnicode } from "./unicode-safety.js";

export interface PromptInjectionFinding {
  kind: "hidden-unicode" | "reversed-tag" | "fake-wrapper" | "role-spoof" | "instruction-smuggling";
  index: number;
  match: string;
}

const PATTERNS: Array<{ kind: PromptInjectionFinding["kind"]; re: RegExp }> = [
  { kind: "reversed-tag", re: />\/?(?:gnikniht|metsys|loot|ekovni|retemarap)(?::lm?tna)?</gi },
  { kind: "fake-wrapper", re: /<\/?(?:system|developer|assistant|tool|invoke|parameter|antml:thinking|thinking)\b[^>]*>/gi },
  { kind: "role-spoof", re: /\b(?:ignore|override|disregard)\s+(?:all\s+)?(?:previous|prior|system|developer)\s+instructions\b/gi },
  { kind: "instruction-smuggling", re: /\b(?:system\s+prompt|developer\s+message|hidden\s+instructions?|reveal\s+your\s+prompt|repeat\s+your\s+instructions)\b/gi },
];

export function findPromptInjection(text: string): PromptInjectionFinding[] {
  const findings: PromptInjectionFinding[] = findHiddenUnicode(text).map((hit) => ({
    kind: "hidden-unicode",
    index: hit.index,
    match: hit.codePoint,
  }));

  for (const { kind, re } of PATTERNS) {
    re.lastIndex = 0;
    for (const match of text.matchAll(re)) {
      findings.push({ kind, index: match.index, match: match[0].slice(0, 80) });
    }
  }

  return findings.sort((a, b) => a.index - b.index);
}