import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
import { runCompaction } from "./compaction";
import { loadCompactionConfig } from "./config";
import { restoreSessionOverride } from "./state";
import { DEFAULT_CONFIG } from "./config";
import type { CompactionState } from "./types";

export default function compaction(pi: ExtensionAPI) {
  const state: CompactionState = {
    config: DEFAULT_CONFIG,
    configSource: "defaults",
    sessionOverride: null,
    lastRun: null,
  };

  function loadState(ctx: any): void {
    const loaded = loadCompactionConfig(ctx.cwd);
    state.config = loaded.config;
    state.configSource = loaded.source;
    state.sessionOverride = restoreSessionOverride(ctx.sessionManager);
    state.lastRun = null;
  }

  pi.on("session_start", async (_event, ctx) => {
    loadState(ctx);
  });

  pi.on("session_switch", async (_event, ctx) => {
    loadState(ctx);
  });

  pi.on("session_before_compact", async (event, ctx) => {
    return await runCompaction(event, ctx, state);
  });
}