/**
 * CLEAN GROUND's declared cast, read from the document rather than copied out of it.
 *
 * Two guards now measure that scenario's own encounter — check-firstblood and
 * check-attackers — and both must be measuring the people the document actually casts.
 * A cast written out by hand in either of them would go on measuring the old six after a
 * re-cast and report success, which is the defect this project keeps finding in itself.
 * R-267 committed exactly that inside the guard built to prevent a weaker version of it.
 *
 * One reader rather than two, because two copies of this would be the duplication
 * check-rules exists to forbid, and would let the two guards disagree about who is in the
 * fight. check-rollable established the `<!-- cast: ... -->` marker; this reads the same
 * one and asks nothing further of the document.
 *
 * NOT named scenario-something: check-scenarios sweeps `tools/scenario-*` into the
 * scenario corpus, so a file with that prefix has its prose read as a scenario's and the
 * marker quoted below read as a real cast declaration. It was, and check-rollable said so.
 */
import { existsSync, readFileSync } from "node:fs";
import path from "node:path";

const ROOT = path.resolve(path.dirname(new URL(import.meta.url).pathname.replace(/^\/([A-Za-z]:)/, "$1")), "..");
export const SCENARIO = path.join(ROOT, "docs", "scenarios", "CLEAN_GROUND.md");

/* The scaling note drops Pollard at five and Okonkwo as well at four, so the cut is the
   declared cast less those two. Named rather than sliced: "the first four" would survive
   a reordering of the cast list and quietly measure different people. */
const DROPPED_AT_FOUR = ["pollard", "okonkwo"];

/* A DECLARATION AND A MENTION OF ONE LOOK IDENTICAL TO A REGEX. CLEAN_GROUND.md carries the
   real marker under "## Casting" and, ten lines later, the warning that explains it —
   `<!-- cast: -->` inside backticks, which matches this pattern with an empty capture. Both
   readers took `.match()`, the FIRST hit, so the whole arrangement worked because the
   declaration happens to come first. Move the warning above the list, or add a second
   worked example, and the guards read a cast of nobody without saying so; check-firstblood
   and check-attackers would then measure a fight this scenario does not cast, which is the
   defect declared-cast.mjs was written to prevent, arriving through the door it left open.
   R-268 already had this exact bug from the other side, when a tools file's own example was
   read as a real declaration.

   So: code spans and fenced blocks are blanked before scanning (padded, so line numbers
   still point at the source), and more than one surviving marker is fatal rather than
   first-wins. */
const CODE = /```[\s\S]*?```|`[^`\n]*`/g;
const scannable = text => text.replace(CODE, m => " ".repeat(m.length));
const lineAt = (text, i) => text.slice(0, i).split("\n").length;

/* `cast\s*:` rather than `cast:`. Tested on strings rather than by editing the scenario, and
   the spacing is why: `<!-- cast : ... -->` was invisible — no marker, so check-rollable fell
   back to the whole duty roster and went green, and R-288 could not catch it because there was
   nothing present to be empty. Putting a space before a colon is not an exotic mistake. It is
   the check-cited defect exactly, where `Cite:`, `CITE:` and `cite :` all failed open while the
   guard reported a count identical to a clean tree. */
export function castMarkersIn(text) {
  return [...scannable(text).matchAll(/<!--\s*cast\s*:\s*([^>]*?)\s*-->/gi)]
    .map(m => ({ keys: m[1], line: lineAt(text, m.index) }));
}

/* ANYTHING a person might have meant as a cast declaration, however spelled. Deliberately
   ASYMMETRIC with the reader above: the reader accepts what the format specifies, this
   recognises anything cast-shaped, and the difference is reported rather than skipped. Widening
   `castMarkersIn` fixes the spelling we thought of; this is what names the one we did not. A
   marker nothing reads is worse than no marker, because whoever wrote it believes the cast is
   declared.

   `cast\w*` catches casting/caster too, so an ordinary comment near the casting section can trip
   it. That is the intended direction: a false alarm costs a reword, and the message says a
   comment meant as prose belongs in backticks or a fence, where nothing here looks at it. The
   opposite error costs a guard that checks the wrong six people and says OK. */
export function castLikeIn(text) {
  const text2 = scannable(text);
  const covered = [...text2.matchAll(/<!--\s*cast\s*:\s*([^>]*?)\s*-->/gi)]
    .map(m => [m.index, m.index + m[0].length]);
  return [...text2.matchAll(/<!--[^>]*\bcast\w*\b[^>]*-->/gi)]
    .filter(m => !covered.some(([a, b]) => m.index >= a && m.index < b))
    .map(m => ({ raw: m[0].trim().slice(0, 80), line: lineAt(text, m.index) }));
}

/** The six the document declares, without their `pc_` prefixes. Fatal if it declares none. */
export function declaredCast(who = "scenario-cast") {
  if (!existsSync(SCENARIO)) {
    console.error(`${who}: ${path.relative(ROOT, SCENARIO)} is missing, and the cast is read `
      + `from it. Nothing here can be measured against a scenario that is not there.`);
    process.exit(1);
  }
  const rel = path.relative(ROOT, SCENARIO);
  const markers = castMarkersIn(readFileSync(SCENARIO, "utf8"));
  if (!markers.length) {
    console.error(`${who}: ${rel} declares no cast. Add the `
      + `<!-- cast: ... --> marker check-rollable already reads, or this guard is measuring `
      + `a fight the scenario no longer casts.`);
    process.exit(1);
  }
  if (markers.length > 1) {
    console.error(`${who}: ${rel} carries ${markers.length} cast markers, at lines `
      + `${markers.map(m => m.line).join(", ")}. Reading the first one is how this guard would `
      + `measure a fight the scenario does not cast while reporting success. One declaration; `
      + `write any example inside backticks or a fenced block, where this reader ignores it.`);
    process.exit(1);
  }
  return markers[0].keys.split(",").map(x => x.trim().replace(/^pc_/, "")).filter(Boolean);
}

/** The declared cast and its four-player cut, checked for the shape the guards recorded. */
export function castAndCut(who = "scenario-cast") {
  const line = declaredCast(who);
  const cut = line.filter(k => !DROPPED_AT_FOUR.includes(k));
  if (cut.length !== 4 || line.length !== 6) {
    console.error(`${who}: CLEAN GROUND now casts ${line.length} and its four-player cut works `
      + `out at ${cut.length}. The recorded fights are six against six and four against three; `
      + `re-read the scaling note and re-record with --update rather than reverting.`);
    process.exit(1);
  }
  return { line, cut };
}