/**
 * The oracle in a terminal. The forge runs this on a pty when someone
 * `ssh`es to the app, with FORGE_APP_DATA pointing at the same ledger the
 * web page reads: j/k move, enter opens nothing because everything is
 * already on screen, `a` asks, `r`/`w` score the verdict under the cursor,
 * `u` takes a score back, `q` leaves. Plain ANSI, no dependencies.
 */

import * as ledger from "./db.ts";
import { calibrate, verdictOnItself } from "./oracle.ts";

const db = ledger.open();
const where =
  process.env.FORGE_APP_ENV === "preview"
    ? `preview of #${process.env.FORGE_APP_PULL ?? "?"}`
    : (process.env.FORGE_APP_ENV ?? "local");

const esc = "\x1b[";
const out = (s: string): void => {
  process.stdout.write(s);
};
const dim = (s: string): string => `${esc}2m${s}${esc}0m`;
const bold = (s: string): string => `${esc}1m${s}${esc}0m`;
const green = (s: string): string => `${esc}32m${s}${esc}0m`;
const red = (s: string): string => `${esc}31m${s}${esc}0m`;

let cursor = 0;
let typing: string | undefined;
let flash = "";

function mark(row: ledger.Row): string {
  if (row.outcome === "right") return green("right");
  if (row.outcome === "wrong") return red("wrong");
  return dim("unjudged");
}

function draw(): void {
  const rows = ledger.ledger(db, "all", 100);
  if (cursor >= rows.length) cursor = Math.max(0, rows.length - 1);
  const width = Math.max(40, (process.stdout.columns ?? 80) - 2);
  const clip = (s: string, n: number): string =>
    s.length <= n ? s : `${s.slice(0, Math.max(0, n - 1))}…`;
  out(`${esc}2J${esc}H`);
  out(`${bold("the oracle")} ${dim(`· ${where} · ${rows.length} verdict${rows.length === 1 ? "" : "s"}`)}\r\n`);
  out(`${dim(verdictOnItself(calibrate(ledger.scored(db))))}\r\n\r\n`);
  if (rows.length === 0) out(dim("  nothing asked yet — press a\r\n"));
  for (const [i, row] of rows.entries()) {
    const here = i === cursor;
    out(`${here ? bold("▸ ") : "  "}${clip(row.question, width - 22)}\r\n`);
    out(`    ${dim(`${row.confidence}% · ${mark(row)}`)}\r\n`);
    if (here) out(`    ${clip(row.stance, width - 6)}\r\n    ${dim(clip(row.auspice, width - 6))}\r\n`);
  }
  out(`\r\n${flash === "" ? dim("j/k move · a ask · r right · w wrong · u unjudge · q quit") : flash}\r\n`);
  if (typing !== undefined) out(`\r\n${bold("ask:")} ${typing}${dim("▏")}\r\n`);
}

function judgeUnderCursor(outcome: "right" | "wrong" | "unjudged"): void {
  const rows = ledger.ledger(db, "all", 100);
  const row = rows[cursor];
  if (row === undefined) return;
  ledger.judge(db, row.id, outcome);
  flash = dim(`scored #${row.id} ${outcome}`);
}

function key(data: Buffer): void {
  const s = data.toString("utf8");
  if (typing !== undefined) {
    if (s === "\r" || s === "\n") {
      const question = typing.trim();
      typing = undefined;
      if (question !== "") {
        const row = ledger.ask(db, question);
        flash = dim(`the oracle: ${row.stance}`);
        cursor = 0;
      }
    } else if (s === "\x7f") typing = typing.slice(0, -1);
    else if (s === "\x1b" || s === "\x03") typing = undefined;
    else if (s >= " " && typing.length < 280) typing += s;
    draw();
    return;
  }
  flash = "";
  if (s === "q" || s === "\x03" || s === "\x04") {
    out(`${esc}2J${esc}H`);
    db.close();
    process.exit(0);
  } else if (s === "j" || s === `${esc}B`) cursor += 1;
  else if (s === "k" || s === `${esc}A`) cursor = Math.max(0, cursor - 1);
  else if (s === "a") typing = "";
  else if (s === "r") judgeUnderCursor("right");
  else if (s === "w") judgeUnderCursor("wrong");
  else if (s === "u") judgeUnderCursor("unjudged");
  draw();
}

if (process.stdin.isTTY) process.stdin.setRawMode(true);
process.stdin.on("data", key);
process.stdout.on("resize", draw);
draw();