import { prisma } from "../db/prisma.js";
import { techStepClassifier } from "../lib/recipe-matching/tech-step-matcher.js";

/**
 * Recomputes every existing `Step`'s `StepTechStep` sequence against the
 * *current* classifier (`tech-step-matcher.ts`/`tech-step-training-data.ts`),
 * the same way `updateRecipe` does when a user resaves a recipe through the
 * UI — always `"fr"` (`DEFAULT_TECH_STEP_LOCALE` in `recipe.service.ts`;
 * there's no persisted per-recipe locale to recover for a step that already
 * exists, so this matches real resave behavior exactly rather than
 * guessing).
 *
 * Needed because tech-step detection only ever runs at create/update time
 * (`recipe.service.ts`'s `matchStepsTechSteps`), never retroactively — a
 * step saved before a classifier/corpus change (new vocabulary, or the
 * `contextStart`/`contextEnd` columns a previous session added) keeps
 * whatever it was matched with at the time until it's next resaved.
 *
 * Exported (not just called from this file's own CLI guard below) so
 * `retrain-tech-steps.ts` can run it as one step of its own larger
 * maintainer workflow, without shelling out to a second process.
 *
 * Safe to re-run: each step's technique sequence is fully replaced (delete
 * + recreate) from the classifier's current output, same as a real edit —
 * running it twice in a row with no corpus change in between is a no-op.
 */
export async function backfillTechSteps(): Promise<{ total: number; changed: number }> {
  const steps = await prisma.step.findMany({ select: { id: true, description: true } });
  console.info(`Recomputing tech steps for ${steps.length} step(s)...`);

  let changed = 0;
  for (const step of steps) {
    const matches = await techStepClassifier.matchTechStepSpans(step.description, "fr");
    await prisma.$transaction([
      prisma.stepTechStep.deleteMany({ where: { stepId: step.id } }),
      prisma.stepTechStep.createMany({
        data: matches.map((match, order) => ({
          stepId: step.id,
          techStepId: match.techStepId,
          order,
          start: match.start,
          end: match.end,
          contextStart: match.contextStart,
          contextEnd: match.contextEnd,
        })),
      }),
    ]);
    changed += 1;
  }

  console.info(`Done — ${changed} step(s) recomputed.`);
  return { total: steps.length, changed };
}

// Only runs when this file is executed directly (`tsx
// src/scripts/backfill-tech-steps.ts`), not when `retrain-tech-steps.ts`
// imports `backfillTechSteps` above — the standard ESM "is this the entry
// module" check, first needed in this codebase by that new script; every
// prior script here (`seed-runtime.ts`) was always only ever run directly,
// never imported.
const isMainModule = import.meta.url === `file://${process.argv[1]}`;
if (isMainModule) {
  backfillTechSteps()
    .then(() => prisma.$disconnect())
    .catch(async (err) => {
      console.error(err);
      await prisma.$disconnect();
      process.exit(1);
    });
}