import { app } from "electron";
import fs from "node:fs";
import path from "node:path";
import type { AppSettings } from "../shared/types";

export const DEFAULT_APP_SETTINGS: AppSettings = {
  browserElementWaitMs: 5000,
  aiConfig: { baseUrl: "", apiKey: "", model: "", visionModel: "" }
};

let cache: AppSettings | null = null;

function settingsPath(): string {
  return path.join(app.getPath("userData"), "settings.json");
}

function normalizeSettings(value: unknown): AppSettings {
  const source = (value && typeof value === "object" ? value : {}) as Partial<AppSettings>;
  const wait = Number(source.browserElementWaitMs);
  const ai = (source.aiConfig && typeof source.aiConfig === "object" ? source.aiConfig : {}) as Partial<AppSettings["aiConfig"]>;
  return {
    browserElementWaitMs: Number.isFinite(wait)
      ? Math.min(600000, Math.max(0, Math.round(wait)))
      : DEFAULT_APP_SETTINGS.browserElementWaitMs,
    aiConfig: {
      baseUrl: String(ai.baseUrl ?? ""),
      apiKey: String(ai.apiKey ?? ""),
      model: String(ai.model ?? ""),
      visionModel: String(ai.visionModel ?? "")
    }
  };
}

export function loadSettings(): AppSettings {
  try {
    cache = normalizeSettings(JSON.parse(fs.readFileSync(settingsPath(), "utf8")));
  } catch {
    cache = { ...DEFAULT_APP_SETTINGS };
  }
  return cache;
}

export function saveSettings(settings: AppSettings): AppSettings {
  const normalized = normalizeSettings(settings);
  fs.mkdirSync(app.getPath("userData"), { recursive: true });
  fs.writeFileSync(settingsPath(), JSON.stringify(normalized, null, 2), "utf8");
  cache = normalized;
  return normalized;
}

export function updateSettings(patch: Partial<AppSettings> = {}): AppSettings {
  return saveSettings({ ...(cache || loadSettings()), ...patch });
}