#!/usr/bin/env bun
import * as fs from 'node:fs';
import * as path from 'node:path';
import { atomicWriteSync } from '../lib/fs-atomic.ts';
import { assessOfficeHoursReviews, loadOfficeHoursReviews, officeHoursDesignChanges, officeHoursMaxRounds, officeHoursSnapshotChanges, officeHoursVerdictReceipt, parseOfficeHoursVerdictReceipt, renderOfficeHoursReview, renderOfficeHoursReviewerPrompt, replaceOfficeHoursReviewBlock, verifyOfficeHoursCitations, verifyOfficeHoursVerdictReceipt } from '../lib/office-hours-review.ts';

const shellQuote = value => `'${value.replaceAll("'", `'\\''`)}'`;

function main(args) {
  const command = args.shift();
  if (!['check', 'prepare', 'seal', 'finalize'].includes(command)) throw new Error('usage: gstack-office-hours-review check --receipt <reviewer response> <round.json...> | prepare --design <doc> --out-dir <reviewdir> [round.json...] | seal --design <doc> --verdict <round-N.json> [preceding round.json...] | finalize --design <doc> [--report <report>] [--unreviewed <reason>] <round.json...> (each also takes --max-rounds 1|2|3, default 3)');
  const options = {};
  const files = [];
  while (args.length) {
    const value = args.shift();
    if (value.startsWith('--')) {
      const allowed = [...{ check: ['--receipt'], prepare: ['--design', '--out-dir'], seal: ['--design', '--verdict'], finalize: ['--design', '--report', '--unreviewed'] }[command], '--max-rounds'];
      if (!allowed.includes(value)
          || options[value] !== undefined || !args.length) throw new Error(`invalid option: ${value}`);
      options[value] = args.shift();
    } else files.push(value);
  }
  const maxRounds = officeHoursMaxRounds(options['--max-rounds']);
  const rounds = loadOfficeHoursReviews(files, maxRounds);
  if (command === 'check') {
    // The receipt binds the reviewer's response to the last round's exact bytes.
    if (!options['--receipt'] || !files.length) throw new Error('check requires --receipt with the reviewer response and every completed round');
    const last = files.at(-1);
    const named = parseOfficeHoursVerdictReceipt(options['--receipt']).path;
    const same = fs.existsSync(named) && fs.realpathSync(named) === fs.realpathSync(last);
    verifyOfficeHoursVerdictReceipt(options['--receipt'], { round: files.length, verdictPath: same ? named : last, bytes: fs.readFileSync(last) });
    console.log(JSON.stringify(assessOfficeHoursReviews(rounds, maxRounds)));
    return;
  }
  if (!options['--design']) throw new Error(`${command} requires --design`);
  const designPath = path.resolve(options['--design']);
  if (rounds.some(review => path.resolve(review.document) !== designPath)) throw new Error('artifact document does not match --design');
  if (command === 'seal') {
    if (!options['--verdict']) throw new Error('seal requires --verdict');
    const verdictPath = path.resolve(options['--verdict']);
    const round = rounds.length + 1;
    if (path.basename(verdictPath) !== `round-${round}.json`) throw new Error(`verdict must be round-${round}.json after the supplied history`);
    const bytes = fs.readFileSync(verdictPath);
    let value;
    try { value = JSON.parse(bytes.toString('utf8')); }
    catch (error) { throw new Error(`saved verdict is invalid JSON: ${error instanceof Error ? error.message : String(error)}`); }
    const review = assessOfficeHoursReviews([...rounds, value], maxRounds).rounds.at(-1);
    if (path.resolve(review.document) !== designPath) throw new Error('verdict document does not match --design');
    if (round > 1) verifyOfficeHoursCitations(review, officeHoursSnapshotChanges(verdictPath, round).changed);
    console.log(officeHoursVerdictReceipt(round, verdictPath, bytes));
    return;
  }
  if (command === 'prepare') {
    if (!options['--out-dir']) throw new Error('prepare requires --out-dir');
    if (!fs.statSync(designPath).isFile()) throw new Error('design must be an existing file');
    const outDir = fs.realpathSync(options['--out-dir']);
    if (!fs.statSync(outDir).isDirectory()) throw new Error('out-dir must be an existing directory');
    const round = rounds.length + 1;
    const promptPath = path.join(outDir, `round-${round}.prompt.md`);
    const verdictPath = path.join(outDir, `round-${round}.json`);
    // Each round records the exact design it reviewed; later rounds see the diff since then.
    const snapshotPath = path.join(outDir, `round-${round}.design.md`);
    const design = fs.readFileSync(designPath, 'utf8');
    let changes;
    if (round > 1 && assessOfficeHoursReviews(rounds, maxRounds).stop !== 'CONTINUE') throw new Error('cannot prepare another round after a terminal review');
    if (round > 1) {
      const before = path.join(outDir, `round-${round - 1}.design.md`);
      if (!fs.existsSync(before)) throw new Error(`out-dir lacks round-${round - 1}.design.md; prepare every round in the same review directory`);
      changes = officeHoursDesignChanges(fs.readFileSync(before, 'utf8'), design).diff;
    }
    const prompt = renderOfficeHoursReviewerPrompt({ document: designPath, verdictPath, previous: rounds.at(-1), changes, maxRounds });
    const inputs = new Set([fs.realpathSync(designPath), ...files.map(file => fs.realpathSync(file))]);
    for (const destination of [promptPath, verdictPath, snapshotPath]) {
      if (fs.existsSync(destination) && inputs.has(fs.realpathSync(destination))) throw new Error('output destination overlaps input evidence');
    }
    if (fs.lstatSync(verdictPath, { throwIfNoEntry: false })) throw new Error('next verdict already exists; check it before preparing another attempt');
    const captured = fs.lstatSync(snapshotPath, { throwIfNoEntry: false });
    if (captured && (!captured.isFile() || fs.readFileSync(snapshotPath, 'utf8') !== design)) throw new Error(`the design changed after round ${round} was prepared`);
    const existing = fs.lstatSync(promptPath, { throwIfNoEntry: false });
    if (existing && (!existing.isFile() || fs.readFileSync(promptPath, 'utf8') !== prompt)) throw new Error('existing review prompt differs from the complete saved evidence');
    if (!captured) atomicWriteSync(snapshotPath, design, { mode: 0o600 });
    if (!existing) atomicWriteSync(promptPath, prompt, { mode: 0o600 });
    const seal = [shellQuote(fs.realpathSync(process.argv[1])), 'seal', ...(maxRounds === 3 ? [] : [`--max-rounds ${maxRounds}`]), '--design', shellQuote(designPath), '--verdict', shellQuote(verdictPath), ...files.map(file => shellQuote(fs.realpathSync(file)))].join(' ');
    const dispatch = `Read ${JSON.stringify(promptPath)} and execute the independent spec review as instructed.\nDocument: ${designPath}\nPrompt: ${promptPath}\nVerdict: ${verdictPath}\nSeal: ${seal}`;
    console.log(JSON.stringify({ round, promptPath, verdictPath, dispatch }));
    return;
  }
  const reportPath = options['--report'] ? path.resolve(options['--report']) : null;
  if (reportPath === designPath) throw new Error('design and report must be different files');
  const inputs = new Set(files.map(file => fs.realpathSync(file)));
  for (const destination of [designPath, reportPath].filter(Boolean)) {
    if (inputs.has(fs.realpathSync(destination))) throw new Error('output destination overlaps a review artifact');
  }
  if (reportPath && fs.realpathSync(reportPath) === fs.realpathSync(designPath)) throw new Error('design and report must be different files');
  const rendered = renderOfficeHoursReview(rounds, options['--unreviewed'], maxRounds);
  // Validate/read/render both destinations before publishing either. Each rename
  // is atomic; any publication error fails the command and final verification.
  const design = fs.readFileSync(designPath, 'utf8');
  const report = reportPath ? fs.readFileSync(reportPath, 'utf8') : '';
  const nextDesign = replaceOfficeHoursReviewBlock(design, 'concerns', rendered.concerns);
  const nextReport = reportPath ? replaceOfficeHoursReviewBlock(report, 'report', rendered.report) : null;
  if (nextDesign !== design) atomicWriteSync(designPath, nextDesign, { mode: fs.statSync(designPath).mode & 0o777 });
  if (reportPath && nextReport !== null && nextReport !== report) atomicWriteSync(reportPath, nextReport, { mode: fs.statSync(reportPath).mode & 0o777 });
  console.log(JSON.stringify({ stop: rendered.stop, metrics: rendered.metrics, report: rendered.report }));
}

try { main(process.argv.slice(2)); }
catch (error) {
  console.error(`gstack-office-hours-review: ${error instanceof Error ? error.message : String(error)}`);
  process.exitCode = 1;
}