/**
 * 应用级Canvas运行时装配点。一次安装模型registry与React renderer目录，按账户/工作区创建runtime，
 * 按项目root安装Foundry服务适配。组件只装配依赖，业务根、history、ledger和持久化仍由下层实例管理。
 * 真实宿主卸载才关闭项目；单个画布页面切换只借还视图，不在这里每次重建engine。
 */
"use client";

import { createContext, useContext, useEffect, useRef, useState, type ReactNode } from "react";
import { defaultCanvasRenderers } from "@/components/canvas/canvas-renderers";
import { createReactRenderers, type CanvasRuntimeExtension } from "@/lib/canvas-bindings/react-flow";
import { notify } from "@/lib/notifications";
import { errorText } from "@/lib/api";
import { createRegistry, builtinComponents } from "@/lib/canvas-core/index";
import { createRuntimeHost, createWorkspaceRuntime, type RuntimeHost } from "@/lib/canvas-runtime/index";
import { createBrowserDigests, createBrowserImageDecoder, createBrowserStorage } from "@/lib/canvas-runtime/browser";
import { createFoundryAssets, createFoundryPersistence, createFoundryTransport, createFoundryRuns,createFoundryModelLoader } from "@/lib/canvas-service/index";

/** 应用共享RuntimeHost引用，未装配时为null；renderer Context另有内置显示目录默认值。 */
const Context = createContext<RuntimeHost | null>(null);
/** 模型定义与显示实现一起在宿主初始化捕获，子页面用此目录保持一致解释。 */
const Renderers=createContext(defaultCanvasRenderers);
/** 读取宿主安装的React renderer集合，不为每个节点重新构造类型表。 */
export function useCanvasRenderers(){return useContext(Renderers);}
/** extensions仅在useState惰性初始化时捕获；后续prop换引用不会热替换已打开项目的schema/renderer。 */
export function CanvasRuntimeHost({ children,extensions=[] }: { children: ReactNode;extensions?:readonly CanvasRuntimeExtension[] }) {
  // 惰性初始化只装配对象/工厂，不在 render 直接打开项目；实际账户绑定和持久化租约由后续调用取得。
  const [{host,renderers}] = useState(() => {
    // 先组合内置与扩展模型，再按精确版本/结构验证renderer，冲突在打开项目之前失败。
    const registry = createRegistry([...builtinComponents(),...extensions.flatMap(extension=>extension.components??[])]),renderers=createReactRenderers([...defaultCanvasRenderers.definitions,...extensions.flatMap(extension=>extension.renderers??[])],registry);
    const host=createRuntimeHost({ registry,
      /** 每身份作用域绑定transport，current护栏由host提供，流读取也要防换账户后的迟到结果。 */
      modelLoader(accountId,workspaceId,_authEpoch,current){return createFoundryModelLoader({workspaceId,registry,transport:createFoundryTransport({accountId,isCurrentIdentity:current})});},
      /** 工作区持有浏览器存储、摘要/解码池；root项目共享其身份范围，各自再装配业务端口。 */
      workspace(accountId, workspaceId, authEpoch, isCurrentIdentity) {
        return createWorkspaceRuntime({ accountId, workspaceId, authEpoch, isCurrentIdentity, registry, storage: createBrowserStorage(),digests:createBrowserDigests(),images:createBrowserImageDecoder(),
          /** 一项目一组协议适配器；summary策略只压缩已协调回执，不改变网络请求或原始操作身份。 */
          adapters(rootId, current) {
            const transport = createFoundryTransport({ accountId, isCurrentIdentity: current });
            return { runs: createFoundryRuns({ workspaceId, rootId, registry, transport }), persistence: createFoundryPersistence({ workspaceId, rootId, registry, transport, resolvedReceiptPolicy:'summary' }), assets: createFoundryAssets({ workspaceId, transport, project: process.env.NEXT_PUBLIC_FOUNDRY_PROJECT || "endoleap", origin: process.env.NEXT_PUBLIC_FOUNDRY_API_ORIGIN }) };
          },
          // 同工作区错误用稳定通知id更新，不创建另一份任务状态；错误恢复仍须runtime明确操作。
          onError: error => notify({ id: `canvas-runtime:${accountId}:${workspaceId}`, title: "画布同步需要处理", description: errorText(error), level: "error" }),
        });
      },
      onError: error => notify({ id: "canvas-host-close", title: "本地修改尚未保存成功", description: errorText(error), level: "error" }),
    });
    return {host,renderers};
  });
  // effect重放的代次令牌只保护宿主清理，不是账户authEpoch，也不进入持久模型。
  const lifetime = useRef(0);
  /** cleanup延到微任务检查代次：Strict Mode同步重设effect会递增代次，旧cleanup不关闭新挂载宿主。
   * 真正卸载才发起host.close，保存失败由宿主错误回调/日志报告，不在此丢弃根或强行释放leader。 */
  useEffect(() => {
    const generation = ++lifetime.current;
    // cleanup 不等待 close 完成，也不主动重试；异步失败经 host 的错误通道和此处 catch 报告。
    // Strict Mode replays effects synchronously; only a real detach retires the host.
    return () => { queueMicrotask(() => { if (lifetime.current === generation) void host.close().catch(error => console.error("[canvas-host]", error.message)); }); };
  }, [host]);
  return <Context.Provider value={host}><Renderers.Provider value={renderers}>{children}</Renderers.Provider></Context.Provider>;
}
/** 需要runtime的页面必须在根Provider内，缺失装配明确抛错而不偷建一个临时host。 */
export function useCanvasRuntimeHost() {
  const host = useContext(Context);
  if (!host) throw new Error("CanvasRuntimeHost is missing");
  return host;
}