import type { WorkflowPlugin } from '../types'

type MiddlewareHook = Exclude<
  keyof WorkflowPlugin,
  'name' | 'afterWrite' | 'onError' | 'onPartialSuccess'
>
type ObserverHook = 'afterWrite' | 'onError' | 'onPartialSuccess'

export class PluginBus {
  private globals: WorkflowPlugin[] = []

  addGlobal(plugin: WorkflowPlugin): void {
    this.globals.push(plugin)
  }

  async run<T>(
    hook: MiddlewareHook,
    perKey: WorkflowPlugin[],
    ctx: T,
  ): Promise<T> {
    let current = ctx
    for (const plugin of [...this.globals, ...perKey]) {
      const fn = plugin[hook] as ((c: T) => Promise<T>) | undefined
      if (fn) {
        current = await fn.call(plugin, current)
      }
    }
    return current
  }

  async runObserver<T>(
    hook: ObserverHook,
    perKey: WorkflowPlugin[],
    ctx: T,
  ): Promise<void> {
    for (const plugin of [...this.globals, ...perKey]) {
      const fn = plugin[hook] as ((c: T) => Promise<void>) | undefined
      if (fn) {
        await fn.call(plugin, ctx)
      }
    }
  }
}