import type { ExtensionCommandContext } from "@earendil-works/pi-coding-agent";
import { readFileSync, existsSync } from "node:fs";
import { join } from "node:path";
import { homedir } from "node:os";
import { loadSettings } from "./settings.js";

function readAuthJson(): Record<string, { type: string; key: string }> | null {
  const authPath = join(process.env.HOME || homedir(), ".pi", "agent", "auth.json");
  if (!existsSync(authPath)) return null;
  try {
    const raw = readFileSync(authPath, "utf-8");
    const parsed = JSON.parse(raw);
    if (typeof parsed !== "object" || parsed === null || Array.isArray(parsed)) return null;
    return parsed as Record<string, { type: string; key: string }>;
  } catch {
    return null;
  }
}

export async function agentrouterConfigCommand(
  _args: string,
  ctx: ExtensionCommandContext
): Promise<void> {
  const settings = loadSettings(ctx.cwd);

  const lines: string[] = [];
  lines.push(`Agent Router Configuration`);
  lines.push(`========================`);
  lines.push(``);
  lines.push(`API Base: ${settings.api_base}`);
  lines.push(`Debug: ${settings.debug}`);
  lines.push(``);

  // ── auth.json entries (primary) ─────────────────────────────────────────

  const authData = readAuthJson();
  const prefix = settings.provider_prefix ?? "agentrouter";

  if (authData) {
    const authEntries = Object.entries(authData)
      .filter(([name]) => name === prefix || name.startsWith(`${prefix}_`))
      .filter(([, entry]) => entry.type === "api_key" && entry.key)
      .map(([name, entry]) => ({ name, key: entry.key }));

    if (authEntries.length > 0) {
      lines.push(`Credentials (from auth.json):`);
      for (const { name, key } of authEntries) {
        lines.push(`  ${name}: ${key.slice(0, 8)}...`);
      }
      lines.push(``);

      if (settings.api_keys && settings.api_keys.length > 0) {
        lines.push(`(settings.json api_keys ignored — auth.json is active)`);
        lines.push(``);
      }

      ctx.ui.notify(lines.join("\n"), "info");
      return;
    }
  }

  // ── Fallback: settings.json api_keys ────────────────────────────────────

  lines.push(`API Keys: ${settings.api_keys?.length ?? 0} configured (settings.json — deprecated)`);
  lines.push(``);

  if (settings.api_keys) {
    lines.push(`Keys:`);
    settings.api_keys.forEach((key, i) => {
      if (typeof key === "string") {
        const display = key === "$AGENT_ROUTER_API_KEY" ? "$AGENT_ROUTER_API_KEY" : key.slice(0, 8) + "...";
        lines.push(`  [${i}] ${display}`);
      } else {
        lines.push(`  [${i}] id=${key.id ?? i}, key=${key.key.slice(0, 8)}...`);
      }
    });
  }

  ctx.ui.notify(lines.join("\n"), "info");
}