import type { Event, HookType } from "./event-queue.js";

export interface HookConfig {
  startup?: string;
  agent_begin?: string;
  agent_stop?: string;
  shutdown?: string;
}

export interface AgentRuntimeLike {
  processEvent(event: Event): Promise<any>;
}

type EnqueueFn = (event: Omit<Event, "id" | "timestamp">) => Event | null;

export class HookManager {
  private config: HookConfig = {};

  parseConfig(content: string): HookConfig {
    const config: HookConfig = {};
    const lines = content.split("\n");

    let inHooksSection = false;
    let currentHookType: HookType | null = null;

    for (const line of lines) {
      const h2Match = line.match(/^##\s+(.+)$/);
      if (h2Match) {
        if (inHooksSection) {
          // Another ## heading ends the Hooks section
          break;
        }
        if (h2Match[1].trim() === "Hooks") {
          inHooksSection = true;
        }
        continue;
      }

      if (!inHooksSection) continue;

      const h3Match = line.match(/^###\s+(.+)$/);
      if (h3Match) {
        const name = h3Match[1].trim();
        if (name === "startup" || name === "agent_begin" || name === "agent_stop" || name === "shutdown") {
          currentHookType = name;
        } else {
          currentHookType = null;
        }
        continue;
      }

      const instructionMatch = line.match(/^Instruction:\s*(.+)$/);
      if (instructionMatch && currentHookType !== null) {
        config[currentHookType] = instructionMatch[1].trim();
        continue;
      }
    }

    this.config = config;
    return config;
  }

  fire(hookType: HookType, enqueue: EnqueueFn): void {
    const instruction = this.config[hookType];

    enqueue({
      type: "hook",
      payload: {
        hookType,
        ...(instruction !== undefined ? { instruction } : {}),
      },
      source: "hook-manager",
    });
  }

  async fireInline(hookType: HookType, runtime: AgentRuntimeLike): Promise<void> {
    const instruction = this.config[hookType];

    const event: Event = {
      id: 0,
      type: "hook",
      payload: {
        hookType,
        ...(instruction !== undefined ? { instruction } : {}),
      },
      timestamp: new Date(),
      source: "hook-manager-inline",
    };

    await runtime.processEvent(event);
  }
}