// OpenRouter-powered commit summary + small avatar helpers.
import { p4, OpenedFile, statusOf } from "./p4";

const MODEL_KEY = "exd-ai-model";
const KEY_KEY = "exd-ai-key";
// cheap + reliable default; change to a "…:free" model in Settings to pay nothing
export const DEFAULT_MODEL = "openai/gpt-4o-mini";

export function getModel(): string { try { return localStorage.getItem(MODEL_KEY) || DEFAULT_MODEL; } catch { return DEFAULT_MODEL; } }
export function setModel(m: string) { try { localStorage.setItem(MODEL_KEY, m.trim() || DEFAULT_MODEL); } catch {} }
export function getKeyLocal(): string { try { return localStorage.getItem(KEY_KEY) || ""; } catch { return ""; } }
export function setKeyLocal(k: string) { try { localStorage.setItem(KEY_KEY, k.trim()); } catch {} }

// key resolution: localStorage first, else the app-config file (git-ignored)
export async function resolveKey(): Promise<string> {
  const local = getKeyLocal();
  if (local) return local;
  try { return (await p4.readAiKey()) || ""; } catch { return ""; }
}

// generate a commit summary + description from the changed files
export async function aiSummary(files: OpenedFile[]): Promise<{ summary: string; description: string }> {
  const key = await resolveKey();
  if (!key) throw new Error("No OpenRouter API key — set it in Settings");
  const list = files.slice(0, 200).map((f) => `${statusOf(f.action).ch} ${f.depotFile || ""}`).join("\n");
  const res = await fetch("https://openrouter.ai/api/v1/chat/completions", {
    method: "POST",
    headers: { Authorization: `Bearer ${key}`, "Content-Type": "application/json", "X-Title": "Exbyte Depot" },
    body: JSON.stringify({
      model: getModel(),
      max_tokens: 300,
      temperature: 0.3,
      messages: [
        { role: "system", content: "You write concise commit messages for a Perforce/Unreal project. Given a list of changed files (+ added, ± edited, − deleted), reply with ONE short imperative summary line (under 72 chars, no trailing period), then a blank line, then an optional 1-3 line description. Plain text only — no markdown, no code fences, no quotes." },
        { role: "user", content: `Changed files:\n${list}` },
      ],
    }),
  });
  if (!res.ok) {
    const txt = await res.text().catch(() => "");
    throw new Error(`OpenRouter ${res.status}: ${txt.slice(0, 180)}`);
  }
  const data = await res.json();
  const content: string = (data?.choices?.[0]?.message?.content || "").trim();
  if (!content) throw new Error("Empty AI response");
  const lines = content.split("\n");
  const summary = (lines[0] || "").replace(/^["'`*]+|["'`*]+$/g, "").trim();
  const description = lines.slice(1).join("\n").trim();
  return { summary, description };
}

// --- avatar helpers ---
export function initials(name: string, user: string): string {
  const n = (name || "").trim();
  if (n) {
    const p = n.split(/\s+/);
    return (p[0][0] + (p[1]?.[0] || "")).toUpperCase();
  }
  return (user || "?").slice(0, 2).toUpperCase();
}
export function avatarColor(seed: string): string {
  let h = 0;
  for (let i = 0; i < seed.length; i++) h = (h * 31 + seed.charCodeAt(i)) >>> 0;
  return `hsl(${h % 360} 52% 52%)`;
}
// activity level from a unix-epoch last-access string
export function activity(access?: string): "active" | "recent" | "idle" {
  const n = Number(access || 0) * 1000;
  if (!n) return "idle";
  const ago = Date.now() - n;
  if (ago < 60 * 60 * 1000) return "active";        // < 1h
  if (ago < 24 * 60 * 60 * 1000) return "recent";   // < 1d
  return "idle";
}