import { createOpenAI } from "@ai-sdk/openai";
import { createOpenAICompatible } from "@ai-sdk/openai-compatible";
import { type LanguageModel } from "ai";
import { getModelWithProviderById, getSystemModelWithProviderById, getModelWithProviderByIdAny } from "#server/service/llm";
import log4js from "logger";

const logger = log4js.getLogger("APP");

export interface ResolvedProvider {
  name: string;
  apiKey: string | null;
  baseUrl: string | null;
  parseMode: string;
}

export interface ResolvedModel {
  dbId: number;
  modelId: string;
  provider: ResolvedProvider;
}

export function resolveLanguageModel(provider: ResolvedProvider, modelId: string): LanguageModel {
  const baseUrl = provider.baseUrl?.replace(/\/+$/, "") || undefined;
  if (provider.parseMode === "openai") {
    const openai = createOpenAI({
      apiKey: provider.apiKey || undefined,
      baseURL: baseUrl,
    });
    return openai(modelId) as unknown as LanguageModel;
  }
  const openaiCompatible = createOpenAICompatible({
    name: provider.name,
    apiKey: provider.apiKey || undefined,
    baseURL: baseUrl || "https://api.openai.com/v1",
  });
  return openaiCompatible(modelId) as unknown as LanguageModel;
}

export async function resolveModelForUser(
  modelId: number,
  userId: number | null,
): Promise<ResolvedModel | null> {
  const modelRow = userId
    ? await getModelWithProviderById(modelId, userId)
    : await getSystemModelWithProviderById(modelId);
  if (!modelRow) {
    logger.warn("[MODEL-RESOLVER] modelId=%d not found for userId=%s", modelId, userId);
    return null;
  }
  const { model, provider } = modelRow;
  if (!provider.apiKey) {
    logger.warn("[MODEL-RESOLVER] provider has no apiKey, skip");
    return null;
  }
  return {
    dbId: model.id,
    modelId: model.modelId,
    provider: {
      name: provider.name,
      apiKey: provider.apiKey,
      baseUrl: provider.baseUrl,
      parseMode: provider.parseMode,
    },
  };
}

export async function resolveModelAny(modelId: number): Promise<ResolvedModel | null> {
  const modelRow = await getModelWithProviderByIdAny(modelId);
  if (!modelRow) {
    logger.warn("[MODEL-RESOLVER] modelId=%d not found (any)", modelId);
    return null;
  }
  const { model, provider } = modelRow;
  if (!provider.apiKey) {
    logger.warn("[MODEL-RESOLVER] provider has no apiKey, skip");
    return null;
  }
  return {
    dbId: model.id,
    modelId: model.modelId,
    provider: {
      name: provider.name,
      apiKey: provider.apiKey,
      baseUrl: provider.baseUrl,
      parseMode: provider.parseMode,
    },
  };
}

export function toLanguageModel(resolved: ResolvedModel): LanguageModel {
  return resolveLanguageModel(resolved.provider, resolved.modelId);
}