import { defineWrappedResponseHandler } from "#server/utils/handler";
import { R } from "#server/utils/response";
import { resolveCharacterIdentity } from "#server/service/character/identity";
import { createCharacterSession, saveCharacterMessage } from "#server/service/character/session";
import {
  generateTempToken,
  setTempTokenCookie,
  getTempTokenTtlMs,
} from "#server/service/agent/temp-token";
import { getConfigUser, getConfigGlobal } from "#server/utils/context";
import { getCharacterCardBySlug } from "#server/service/character/character-card";

export default defineWrappedResponseHandler(async (event) => {
  const slug = getRouterParam(event, "slug");
  if (!slug) {
    return R.error("参数无效", null);
  }
  const card = await getCharacterCardBySlug(slug);
  if (!card) {
    return R.error("角色不存在", null);
  }

  const identity = await resolveCharacterIdentity(event);

  let tempToken: string | null = null;
  let expiresAt: Date | null = null;

  if (!identity.userId && !identity.tempToken) {
    tempToken = generateTempToken();
    expiresAt = new Date(Date.now() + getTempTokenTtlMs());
    setTempTokenCookie(event, tempToken);
  } else if (!identity.userId && identity.tempToken) {
    tempToken = identity.tempToken;
    expiresAt = new Date(Date.now() + getTempTokenTtlMs());
  }

  let modelId: number | null = null;

  if (identity.userId) {
    const preferred = await getConfigUser(event, "preferredLlmModelId");
    if (preferred && preferred > 0) {
      modelId = preferred;
    }
  }

  if (!modelId && card.defaultModelId) {
    modelId = card.defaultModelId;
  }

  if (!modelId) {
    const globalDefault = await getConfigGlobal("agentDefaultModelId");
    if (globalDefault && globalDefault > 0) {
      modelId = globalDefault;
    }
  }

  const session = await createCharacterSession({
    userId: identity.userId,
    tempToken,
    cardId: card.id,
    modelId,
    expiresAt,
  });

  // 开场白：创建会话时自动写入角色的首条消息
  let greeting = null;
  const firstMessage = card.firstMessage?.trim();
  if (firstMessage) {
    greeting = await saveCharacterMessage({
      sessionId: session.id,
      role: "assistant",
      content: firstMessage,
      sortOrder: 1,
    });
  }

  return R.success({ session, greeting });
});