import type Database from "bun:sqlite";

import type { RuntimeMode } from "../../../shared/api";
import type { Logger } from "../../logger";

import { getConversation, listMessages } from "../../db/conversations";
import { createApiError, jsonResponse } from "../../helpers";
import { validateIdParam, validatePagination } from "../../middleware";

export function handleListMessages(req: Request, db: Database, mode: RuntimeMode, _logger: Logger): Response {
  const parts = new URL(req.url).pathname.split("/");
  const projectId = parts[3];
  const conversationId = parts[5];

  const validatedProject = validateIdParam(projectId ?? "", mode);
  if (validatedProject instanceof Response) return validatedProject;

  const validatedConv = validateIdParam(conversationId ?? "", mode);
  if (validatedConv instanceof Response) return validatedConv;

  const convResult = getConversation(db, validatedConv.id);
  if ("error" in convResult) {
    return jsonResponse(createApiError(convResult.error, convResult.status), { mode, status: convResult.status });
  }

  if (convResult.conversation.projectId !== validatedProject.id) {
    return jsonResponse(createApiError("会话不属于该项目", 403), { mode, status: 403 });
  }

  const url = new URL(req.url);
  const pageParam = url.searchParams.get("page");
  const pageSizeParam = url.searchParams.get("pageSize");

  const pagination = validatePagination(pageParam, pageSizeParam, mode);
  if (pagination instanceof Response) return pagination;

  const result = listMessages(db, validatedConv.id, {
    page: pagination.page,
    pageSize: pagination.pageSize,
  });

  return jsonResponse(result, { mode });
}