import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";

import { registerTodosCommand } from "./command";
import { STATE_ENTRY, WIDGET_KEY } from "./constants";
import { createTodoStore } from "./state";
import { registerTodoTool, registerTodoCompleteAllTool } from "./tool";
import { registerTodoWidget } from "./widget";

const TRACK_PROGRESS_PROMPT = `\
Track work with the todo tools unless the user explicitly says not to:
- \`todo add\` — record each item the user wants tracked (text or texts).
- \`todo update\` — set \`status: completed\` as items finish; update status on every progress change (in-progress, blocked, …).
- \`todo remove\` — drop tasks that are no longer relevant.
- "complete everything" / "done with all" → \`todo_complete_all\`, not a loop of \`todo update\`.`;

export default function (pi: ExtensionAPI): void {
  const store = createTodoStore((snapshot) =>
    pi.appendEntry(STATE_ENTRY, snapshot),
  );

  const panelControls = registerTodoWidget(pi, store);

  registerTodoTool(pi, store);
  registerTodoCompleteAllTool(pi, store);
  registerTodosCommand(pi, store);

  pi.on("session_start", (_event, ctx) => {
    store.replay(ctx);
    panelControls.refresh(ctx);
  });

  pi.on("session_tree", (_event, ctx) => {
    store.replay(ctx);
    panelControls.refresh(ctx);
  });

  pi.on("session_before_compact", (_event, ctx) => store.persistSnapshot(ctx));

  pi.on("before_agent_start", (event) => ({
    systemPrompt: event.systemPrompt + "\n\n" + TRACK_PROGRESS_PROMPT,
  }));

  pi.on("session_shutdown", (_event, ctx) => {
    if (ctx.hasUI) ctx.ui.setWidget(WIDGET_KEY, undefined);
  });
}