import type { ExtensionContext } from "@earendil-works/pi-coding-agent";
import type {
  EvalDetachedCellNotification,
  EvalDetachedCellNotifier,
} from "../tool/detached-cell-manager.ts";

const NON_INTERACTIVE_MODES = new Set(["print", "json"]);

export type EvalNotifyMode = "wake" | "next-turn" | "off";

export interface EvalNotifierDeps {
  readonly getContext: () => ExtensionContext | undefined;
  readonly getMode: () => EvalNotifyMode;
  readonly sendUserMessage: (
    content: string,
    options?: { deliverAs?: "steer" | "followUp" }
  ) => void;
}

/** Session-scoped completion injector with the same no-spin guards as terminal notifications. */
export class EvalNotifier implements EvalDetachedCellNotifier {
  readonly #deps: EvalNotifierDeps;
  readonly #notified = new Set<string>();

  constructor(deps: EvalNotifierDeps) {
    this.#deps = deps;
  }

  /** Starts a fresh session generation without suppressing reused tool-call ids. */
  reset(): void {
    this.#notified.clear();
  }

  notify(cells: readonly EvalDetachedCellNotification[]): void {
    const mode = this.#deps.getMode();
    if (mode === "off") {
      return;
    }
    const ctx = this.#deps.getContext();
    if (
      ctx === undefined ||
      NON_INTERACTIVE_MODES.has(ctx.mode) ||
      ctx.model === undefined
    ) {
      return;
    }
    const pending = cells.filter((cell) => !this.#notified.has(cell.cellId));
    if (pending.length === 0) {
      return;
    }
    for (const cell of pending) {
      this.#notified.add(cell.cellId);
    }
    this.#deps.sendUserMessage(
      pending.map((cell) => cell.content).join("\n\n"),
      {
        deliverAs: mode === "wake" ? "steer" : "followUp",
      }
    );
  }
}