import type { ExtensionCommandContext } from "@earendil-works/pi-coding-agent";
import { runLiveChoice } from "@narumitw/pi-tui-kit";
import type { StarshipPreset } from "./presets/catalog.js";

export type PresetPickerResult =
	| { kind: "apply"; presetId: StarshipPreset["id"] }
	| { kind: "customize"; presetId: StarshipPreset["id"] }
	| { kind: "back" }
	| { kind: "close" };

export interface PresetPickerOptions {
	presets: readonly StarshipPreset[];
	activePresetId?: StarshipPreset["id"];
	initialPresetId?: StarshipPreset["id"];
	signal: AbortSignal;
	isCurrent(): boolean;
	preview(preset: StarshipPreset): void;
}

export async function showPresetPicker(
	ctx: ExtensionCommandContext,
	options: PresetPickerOptions,
): Promise<PresetPickerResult> {
	const current =
		options.presets.find((preset) => preset.id === options.activePresetId)?.label ??
		"Custom configuration";
	const result = await runLiveChoice(ctx, {
		title: `Presets · current: ${current}`,
		items: options.presets.map((preset) => ({
			id: preset.id,
			label: preset.label,
			description:
				preset.id === options.activePresetId
					? `Currently applied · ${preset.description}`
					: preset.description,
			details: [
				`Selected: ${preset.label} · ${preset.requiresNerdFont ? "requires Nerd Font" : "font-safe"}`,
			],
			confirmationDisabled: preset.id === options.activePresetId,
			confirmationDisabledReason: "Already applied; press e to customize",
		})),
		currentItemId: options.activePresetId,
		initialItemId: options.initialPresetId ?? options.activePresetId,
		viewportSize: Math.min(options.presets.length, 10),
		hint: "back",
		navigationLabel: "live preview",
		confirmLabel: "apply",
		shortcuts: [{ id: "customize", keys: ["e", "shift+e"], label: "customize" }],
		onSelectionChange: ({ item }) => {
			const preset = options.presets.find((candidate) => candidate.id === item.id);
			if (preset) options.preview(preset);
		},
		signal: options.signal,
		isCurrent: options.isCurrent,
	});
	if (result.kind === "selected") return { kind: "apply", presetId: result.itemId };
	if (result.kind === "shortcut") {
		return { kind: "customize", presetId: result.itemId };
	}
	if (result.kind === "closed" && result.reason === "back") return { kind: "back" };
	return { kind: "close" };
}