import type { ExtensionAPI } from "@oh-my-pi/pi-coding-agent";
import { inspectNote, notes } from "./notebook";

type NotebookNote = (typeof notes)[number];
type NotebookDetails =
	| { operations: string[]; ids: NotebookNote["id"][]; persistence: "factory-local" }
	| { note: NotebookNote; selected: string | null; changed: boolean }
	| { selected: string | null };

export default function notebookPackage(pi: ExtensionAPI): void {
	const { Type } = pi.typebox;
	// Factory-local state belongs to one binding, not Bun's cached module.
	let selected: string | null = null;
	const parameters = Type.Object({
		op: Type.Union([Type.Literal("discover"), Type.Literal("inspect"), Type.Literal("query"), Type.Literal("act")]),
		id: Type.Optional(Type.String()),
	});
	pi.registerTool<typeof parameters, NotebookDetails>({
		name: "notebook",
		label: "Notebook",
		description: "Discover fictional notes, inspect an id, query the current selection, or act to select an id. Selection lives in this extension binding, including across /new and session switches; it is not persisted.",
		parameters,
		async execute(_callId, params) {
			if (params.op === "discover") {
				const details: NotebookDetails = { operations: ["discover", "inspect", "query", "act"], ids: notes.map(note => note.id), persistence: "factory-local" };
				return { content: [{ type: "text", text: JSON.stringify(details) }], details };
			}
			if (params.op === "inspect" || params.op === "act") {
				const note = inspectNote(params.id ?? "");
				if (params.op === "act") selected = note.id;
				const details = { note, selected, changed: params.op === "act" };
				return { content: [{ type: "text", text: JSON.stringify(details) }], details };
			}
			return { content: [{ type: "text", text: selected ?? "No note selected." }], details: { selected } };
		},
	});
	pi.registerCommand("notebook", {
		description: "Inspect or select a fictional note: /notebook [reed|fern]",
		getArgumentCompletions(prefix) {
			const hits = notes.filter(note => note.id.startsWith(prefix));
			if (!hits.length || (hits.length === 1 && hits[0]?.id === prefix)) return null;
			return hits.map(note => ({ value: `${note.id} `, label: note.id, description: note.text }));
		},
		async handler(args, ctx) {
			if (!args.trim()) {
				ctx.ui.notify(selected ? `Selected: ${selected}.` : "No selection. Try /notebook reed.", "info");
				return;
			}
			try {
				selected = inspectNote(args.trim()).id;
				ctx.ui.notify(`Selected ${selected} for this extension binding; /new and session switches keep it. Verify with /notebook.`, "info");
			} catch (error) {
				ctx.ui.notify(`Nothing changed. ${error instanceof Error ? error.message : String(error)}`, "warning");
			}
		},
	});
}