/**
 * 事件流（SSE，用 fetch 读，API2）：事件只是「有变化」的提示，以资源的 GET 结果为准。
 * 进度事件直接写进解析任务和项目列表的缓存，让进度条即时动；其余事件让相关查询失效、重新请求。
 * 断线由 api-client 自动重连；页面上的 5 秒轮询兜底。
 */
import { subscribeEvents, type BdEvent } from "@bid-doctor/api-client";
import type { QueryClient } from "@tanstack/vue-query";
import { apiOptions } from "./api";
import { qk } from "./keys";
import { TERMINAL_JOB, type CheckRun, type ParseJob, type ProjectListItem } from "./queries";

type ProjectPage = { items: ProjectListItem[]; next_cursor: string | null };

function onEvent(qc: QueryClient, e: BdEvent) {
  const job = e.job;
  const jobId = job?.id;
  if ((e.type === "job.progress" || e.type === "job.finished") && job && jobId && job.kind === "parse_job") {
    // 事件可能比 GET 结果旧（重连补发、乱序）：已结束的任务不再被进度事件改回「进行中」，进度只增不减
    qc.setQueryData<ParseJob>(qk.parseJob(jobId), (old) =>
      !old || TERMINAL_JOB.has(old.status) || (job.progress ?? 0) < old.progress
        ? old
        : {
            ...old,
            status: job.status ?? old.status,
            stage: (job.stage as ParseJob["stage"]) ?? old.stage,
            progress: job.progress ?? old.progress,
          },
    );
    qc.setQueryData<ProjectPage>(qk.projects, (old) =>
      old && {
        ...old,
        items: old.items.map((p) =>
          p.active_job && p.active_job.id === jobId && (job.progress ?? 0) >= (p.active_job.progress ?? 0) ? { ...p, active_job: { ...p.active_job, progress: job.progress ?? p.active_job.progress } } : p,
        ),
      },
    );
    if (e.type === "job.finished") {
      // 结束后要拿完整结果（error、result），并刷新项目、额度、清单
      void qc.invalidateQueries({ queryKey: qk.parseJob(jobId) });
      void qc.invalidateQueries({ queryKey: qk.notifications });
      void qc.invalidateQueries({ queryKey: qk.projects });
      void qc.invalidateQueries({ queryKey: qk.quota });
      if (e.project_id) {
        void qc.invalidateQueries({ queryKey: qk.project(e.project_id) });
        void qc.invalidateQueries({ queryKey: qk.checklist(e.project_id) });
        void qc.invalidateQueries({ queryKey: qk.checklistItems(e.project_id) });
      }
    }
    return;
  }
  if ((e.type === "job.progress" || e.type === "job.finished") && job && jobId && job.kind === "check_run") {
    qc.setQueryData<CheckRun>(qk.checkRun(jobId), (old) =>
      !old || TERMINAL_JOB.has(old.status) || (job.progress ?? 0) < old.progress
        ? old
        : { ...old, status: job.status ?? old.status, stage: (job.stage as CheckRun["stage"]) ?? old.stage, progress: job.progress ?? old.progress },
    );
    if (e.type === "job.finished") {
      void qc.invalidateQueries({ queryKey: qk.checkRun(jobId) });
      void qc.invalidateQueries({ queryKey: qk.notifications });
      void qc.invalidateQueries({ queryKey: qk.findings(jobId) });
      void qc.invalidateQueries({ queryKey: qk.projects });
      void qc.invalidateQueries({ queryKey: qk.quota });
      if (e.project_id) {
        void qc.invalidateQueries({ queryKey: qk.project(e.project_id) });
        void qc.invalidateQueries({ queryKey: qk.checkPreview(e.project_id) });
        void qc.invalidateQueries({ queryKey: qk.checkRuns(e.project_id) });
      }
    }
    return;
  }
  switch (e.type) {
    case "quota.changed":
      void qc.invalidateQueries({ queryKey: qk.quota });
      void qc.invalidateQueries({ queryKey: qk.notifications });
      break;
    case "project.changed":
      void qc.invalidateQueries({ queryKey: qk.projects });
      if (e.project_id) void qc.invalidateQueries({ queryKey: qk.project(e.project_id) });
      break;
    case "resync":
      void qc.invalidateQueries();
      break;
    default:
      // notification.created、report.ready：骨架阶段还没有对应界面
      break;
  }
}

/** 登录后的页面框架挂载时开始订阅，返回取消函数。 */
export function startEventStream(qc: QueryClient): () => void {
  return subscribeEvents(apiOptions, (e) => onEvent(qc, e));
}