/**
 * Fix subject-line stripping: optional colon + multi-line subject block
 */
import fs from "fs";

const SUBJECT_LINE_RE =
  "/(?:\\u4e3b\\u9898|\\u4e3b\\u65e8|Subject)\\s*[\\uFF1A:]?/i";

const helper = `/** Drop subject / \\u4e3b\\u65e8 block (optional colon, multi-line wrap) */\nfunction stripSubjectLines(text: string): string {\n  const lines = text.split(/\\n/);\n  const out: string[] = [];\n  let inSubject = false;\n  for (const line of lines) {\n    if (/(?:\\u4e3b\\u9898|\\u4e3b\\u65e8|Subject)\\s*[\\uFF1A:]?/i.test(line)) {\n      inSubject = true;\n      continue;\n    }\n    if (inSubject) {\n      const t = line.trim();\n      if (!t) {\n        inSubject = false;\n        continue;\n      }\n      if (\n        /^(?:\\u5bc4\\u4ef6\\u4eba|\\u53d1\\u4ef6\\u4eba|\\u6536\\u4ef6\\u4eba|\\u6284\\u9001|\\u65e5\\u671f|\\u53d1\\u9001\\u65f6\\u95f4|From|To|Cc|Date|Sent|Dear|----)/i.test(\n          t,\n        ) ||\n        /^date@/i.test(t) ||\n        t === "date" ||\n        /^[\\u5728\\\\s]*\\d{4}/.test(t)\n      ) {\n        inSubject = false;\n        out.push(line);\n        continue;\n      }\n      continue;\n    }\n    out.push(line);\n  }\n  return out.join("\\n");\n}\n`;

// Simpler: write file with real unicode via \u in the script string that becomes Chinese
const stripFn = `
function stripSubjectLines(text: string): string {
  const lines = text.split(/\\n/);
  const out: string[] = [];
  let inSubject = false;
  for (const line of lines) {
    // "\\u4e3b\\u9898 Re:..." often has NO colon after \\u4e3b\\u9898
    if (/(?:\u4e3b\u9898|\u4e3b\u65e8|Subject)\\s*[\uFF1A:]?/i.test(line)) {
      inSubject = true;
      continue;
    }
    if (inSubject) {
      const t = line.trim();
      if (!t) {
        inSubject = false;
        continue;
      }
      if (
        /^(?:\u5bc4\u4ef6\u4eba|\u53d1\u4ef6\u4eba|\u6536\u4ef6\u4eba|\u6284\u9001|\u65e5\u671f|\u53d1\u9001\u65f6\u95f4|From|To|Cc|Date|Sent|Dear|----)/i.test(
          t,
        ) ||
        /^date@/i.test(t) ||
        t === "date" ||
        /^\u5728\\s*\\d{4}/.test(t)
      ) {
        inSubject = false;
        out.push(line);
        continue;
      }
      continue;
    }
    out.push(line);
  }
  return out.join("\\n");
}
`.trimStart();

{
  const path = "src/services/parse/instruction-lexicon.ts";
  let src = fs.readFileSync(path, "utf8");
  const a = src.indexOf("function stripSubjectLines");
  const b = src.indexOf("export function isForwardShellSegment");
  if (a < 0 || b < 0) throw new Error("markers");
  // keep any comment before function - find from /** Drop or function
  let start = src.lastIndexOf("/** Drop subject", a);
  if (start < 0) start = a;
  src =
    src.slice(0, start) +
    "/** Drop subject/\u4e3b\u65e8 block (optional colon; multi-line wrap) */\n" +
    stripFn +
    "\n" +
    src.slice(b);
  fs.writeFileSync(path, src);
  console.log("lexicon stripSubjectLines updated");
}

{
  const path = "src/services/parse/split-instructions.ts";
  let src = fs.readFileSync(path, "utf8");
  const neu = `function bodyForKindDetect(segBody: string): string {
  // reuse same multi-line subject strip as lexicon (inline copy to avoid circular import)
  const lines = segBody.split(/\\n/);
  const out: string[] = [];
  let inSubject = false;
  for (const line of lines) {
    if (/(?:\u4e3b\u9898|\u4e3b\u65e8|Subject)\\s*[\uFF1A:]?/i.test(line)) {
      inSubject = true;
      continue;
    }
    if (inSubject) {
      const t = line.trim();
      if (!t) {
        inSubject = false;
        continue;
      }
      if (
        /^(?:\u5bc4\u4ef6\u4eba|\u53d1\u4ef6\u4eba|\u6536\u4ef6\u4eba|\u6284\u9001|\u65e5\u671f|\u53d1\u9001\u65f6\u95f4|From|To|Cc|Date|Sent|Dear|----)/i.test(
          t,
        ) ||
        /^date@/i.test(t) ||
        t === "date" ||
        /^\\u5728\\s*\\d{4}/.test(t) ||
        /^\u5728\\s*\\d{4}/.test(t)
      ) {
        inSubject = false;
        out.push(line);
        continue;
      }
      continue;
    }
    out.push(line);
  }
  return out.join("\\n");
}
`;

  const a = src.indexOf("function bodyForKindDetect");
  const b = src.indexOf("export function detectKindsForSegment");
  if (a < 0 || b < 0) throw new Error("bounds");
  src = src.slice(0, a) + neu + "\n" + src.slice(b);
  fs.writeFileSync(path, src);
  console.log("split bodyForKindDetect updated");
}