import { auth } from "@/app/(auth)/auth";
import { getSystemSetting } from "@/lib/db/queries";

type RealtimeCanvasConfig = {
  enabled?: boolean;
  falApiKey?: string;
  apiKey?: string;
  throttleInterval?: number;
  maxBuffering?: number;
  maxInputResolution?: number;
  jpegQuality?: number;
  defaults?: {
    steps?: number;
    scheduleMu?: number;
    feedback?: number;
    imageSize?: "square" | "square_hd";
  };
};

type AngleEditConfig = {
  falApiKey?: string;
};

const defaultConfig = {
  session: {
    idleTimeoutMs: 120000,
  },
  transport: {
    throttleInterval: 100,
    maxBuffering: 2,
  },
  image: {
    maxInputResolution: 1024,
    jpegQuality: 0.55,
  },
  model: {
    id: "fal-ai/flux-2/klein/realtime",
    defaults: {
      steps: 3,
      scheduleMu: 2.3,
      feedback: 0.95,
      imageSize: "square" as const,
    },
    limits: {
      steps: { min: 1, max: 6 },
      feedback: { min: 0.7, max: 1.0 },
    },
  },
  features: {
    history: true,
    abCompare: false,
  },
};

function clamp(value: number, min: number, max: number) {
  return Math.min(max, Math.max(min, value));
}

export async function GET() {
  const session = await auth();
  if (!session?.user?.id) {
    return Response.json({ code: "UNAUTHORIZED", message: "请先登录" }, { status: 401 });
  }

  const [setting, angleEditSetting] = await Promise.all([
    getSystemSetting({ key: "realtime_canvas_config" }).catch(() => null),
    getSystemSetting({ key: "angle_edit_config" }).catch(() => null),
  ]);
  const config = (setting?.value || {}) as RealtimeCanvasConfig;
  const angleEditConfig = (angleEditSetting?.value || {}) as AngleEditConfig;

  if (config.enabled === false) {
    return Response.json(
      { code: "FEATURE_DISABLED", message: "实时画布功能未开启" },
      { status: 403 }
    );
  }

  const falApiKey = String(
    config.falApiKey ||
      config.apiKey ||
      angleEditConfig.falApiKey ||
      process.env.FAL_KEY ||
      process.env.FAL_API_KEY ||
      ""
  ).trim();

  if (!falApiKey) {
    return Response.json(
      {
        code: "FAL_KEY_MISSING",
        message: "未配置实时画布 API Key（请在本地AI设置中配置）",
      },
      { status: 500 }
    );
  }

  const throttleInterval = clamp(
    Number(config.throttleInterval || defaultConfig.transport.throttleInterval),
    60,
    260
  );
  const maxBuffering = clamp(
    Number(config.maxBuffering || defaultConfig.transport.maxBuffering),
    1,
    6
  );
  const maxInputResolution = clamp(
    Number(config.maxInputResolution || defaultConfig.image.maxInputResolution),
    512,
    1536
  );
  const jpegQuality = clamp(
    Number(config.jpegQuality || defaultConfig.image.jpegQuality),
    0.35,
    0.82
  );
  const steps = clamp(Number(config.defaults?.steps || defaultConfig.model.defaults.steps), 1, 6);
  const scheduleMu = clamp(
    Number(config.defaults?.scheduleMu || defaultConfig.model.defaults.scheduleMu),
    1.5,
    3.5
  );
  const feedback = clamp(
    Number(config.defaults?.feedback || defaultConfig.model.defaults.feedback),
    0.7,
    1.0
  );
  const imageSize = config.defaults?.imageSize === "square_hd" ? "square_hd" : "square";

  return Response.json({
    ...defaultConfig,
    transport: {
      throttleInterval,
      maxBuffering,
    },
    image: {
      maxInputResolution,
      jpegQuality,
    },
    model: {
      ...defaultConfig.model,
      defaults: {
        steps,
        scheduleMu,
        feedback,
        imageSize,
      },
    },
  });
}