/**
 * KHAELOR
 * File: src/tui/doctor.ts
 * Description: `khaelor --doctor-tui` — detected terminal capabilities and why, turning display bugs into self-diagnosed tickets (TUI v2 §7).
 *
 * Author: Simon-Pierre Boucher
 * Contact: contact@spboucher.ai
 */

import { detectColorDepth } from "./renderer/capabilities.js";

export interface DoctorEnv {
  TERM?: string;
  COLORTERM?: string;
  NO_COLOR?: string;
  LANG?: string;
  LC_ALL?: string;
  TERM_PROGRAM?: string;
}

/** Terminals known to support OSC 8 hyperlinks / OSC 52 clipboard. */
const OSC8_TERMINALS = new Set(["iTerm.app", "WezTerm", "kitty", "ghostty", "Hyper", "vscode"]);
const OSC52_TERMINALS = new Set(["iTerm.app", "WezTerm", "kitty", "ghostty", "Apple_Terminal"]);

/** Build the --doctor-tui report: what was detected, and the reason. */
export function doctorReport(env: DoctorEnv, isTty: boolean, columns: number): string[] {
  const colorDepth = detectColorDepth(env as NodeJS.ProcessEnv, isTty);
  const utf8 = /utf-?8/i.test(env.LC_ALL ?? env.LANG ?? "");
  const program = env.TERM_PROGRAM ?? "";
  const osc8 = OSC8_TERMINALS.has(program);
  const osc52 = OSC52_TERMINALS.has(program);

  const line = (name: string, value: string, why: string): string =>
    `   ${name.padEnd(16)} ${value.padEnd(18)} ${why}`;

  return [
    "",
    " doctor-tui · detected capabilities",
    line("tty", String(isTty), isTty ? "stdout is a terminal" : "stdout is piped — TUI disabled"),
    line(
      "colors",
      colorDepth,
      env.NO_COLOR !== undefined
        ? "NO_COLOR is set"
        : `COLORTERM=${env.COLORTERM ?? "(unset)"} · TERM=${env.TERM ?? "(unset)"}`,
    ),
    line("unicode", utf8 ? "utf-8" : "ascii-fallback", `LANG=${env.LANG ?? "(unset)"}`),
    line("width", String(columns), columns < 100 ? "narrow layout: 2-line status bar, unified diffs" : "full layout"),
    line("osc8 links", osc8 ? "yes" : "unknown", `TERM_PROGRAM=${program || "(unset)"} — fallback: text (url)`),
    line("osc52 clipboard", osc52 ? "yes" : "unknown", "fallback: copy hint hidden"),
    "",
    "   theme: khaelis (obsidian + magma) · degradation: truecolor → 256 → 16 → mono",
    "   report display bugs with this block attached.",
  ];
}