// 增量种子:把 extra/batch0-3.json 的补充课文写入 grammar_point(不重复,序号续接)
import fs from "node:fs";
import path from "node:path";
import { sql, eq } from "drizzle-orm";
import { drizzle } from "drizzle-orm/mysql2";
import mysql from "mysql2/promise";
import { grammarPoints } from "../src/db/schema";

type Extra = { id: string; title: string; cefr: string; difficulty: number; summary: string; md: string };

const levelOf = (cefr: string) =>
  cefr === "A1" ? { level: "starter", name: "入门" } : cefr === "A2" ? { level: "base", name: "基础" } : { level: "pro", name: "进阶" };

async function main() {
  const conn = await mysql.createConnection(process.env.DATABASE_URL!);
  const db = drizzle(conn);

  const [mx] = await db.select({ m: sql<number>`COALESCE(MAX(seq),0)` }).from(grammarPoints);
  let seq = mx.m;

  const existing = new Set((await db.select({ pointId: grammarPoints.pointId }).from(grammarPoints)).map((r) => r.pointId));

  let added = 0;
  for (const f of ["batch0.json", "batch1.json", "batch2.json", "batch3.json"]) {
    const p = path.join(process.cwd(), "src/content/grammar/extra", f);
    if (!fs.existsSync(p)) continue;
    const arr = JSON.parse(fs.readFileSync(p, "utf8")) as Extra[];
    for (const e of arr) {
      if (existing.has(e.id)) continue;
      seq += 1;
      const lv = levelOf(e.cefr);
      await db.insert(grammarPoints).values({
        pointId: e.id,
        level: lv.level,
        levelName: lv.name,
        title: e.title,
        difficulty: e.difficulty || 1,
        summary: e.summary,
        prereq: "[]",
        md: e.md,
        seq,
      });
      added++;
    }
  }
  const [tot] = await db.select({ n: sql<number>`COUNT(*)` }).from(grammarPoints);
  console.log("新增补充课:", added, "| 总知识点:", tot.n);
  await conn.end();
}

main();