import { OverrideLevel } from '$lib/proto/llm_multiverse/v1/common_pb';

export interface PresetConfig {
	overrideLevel: OverrideLevel;
	disabledTools: string[];
	grantedPermissions: string[];
}

export interface Preset {
	name: string;
	config: PresetConfig;
	builtIn: boolean;
}

const STORAGE_KEY = 'llm-multiverse-presets';

const builtInPresets: Preset[] = [
	{
		name: 'Strict mode',
		config: {
			overrideLevel: OverrideLevel.NONE,
			disabledTools: ['FS Write', 'Run Shell', 'Run Code', 'Package Install'],
			grantedPermissions: []
		},
		builtIn: true
	},
	{
		name: 'Research only',
		config: {
			overrideLevel: OverrideLevel.NONE,
			disabledTools: ['Memory Write', 'FS Write', 'Run Code', 'Run Shell', 'Package Install'],
			grantedPermissions: []
		},
		builtIn: true
	},
	{
		name: 'Full access',
		config: {
			overrideLevel: OverrideLevel.ALL,
			disabledTools: [],
			grantedPermissions: []
		},
		builtIn: true
	}
];

function loadCustomPresets(): Preset[] {
	if (typeof localStorage === 'undefined') return [];
	try {
		const raw = localStorage.getItem(STORAGE_KEY);
		if (!raw) return [];
		const parsed: Preset[] = JSON.parse(raw);
		return parsed.map((p) => ({ ...p, builtIn: false }));
	} catch {
		return [];
	}
}

function saveCustomPresets(presets: Preset[]) {
	if (typeof localStorage === 'undefined') return;
	const custom = presets.filter((p) => !p.builtIn);
	localStorage.setItem(STORAGE_KEY, JSON.stringify(custom));
}

function createPresetStore() {
	const customPresets = $state<Preset[]>(loadCustomPresets());

	function getAllPresets(): Preset[] {
		return [...builtInPresets, ...customPresets];
	}

	function savePreset(name: string, config: PresetConfig): Preset {
		const trimmed = name.trim();
		if (!trimmed) throw new Error('Preset name cannot be empty');
		if (builtInPresets.some((p) => p.name === trimmed)) {
			throw new Error('Cannot overwrite a built-in preset');
		}

		const existing = customPresets.findIndex((p) => p.name === trimmed);
		const preset: Preset = { name: trimmed, config, builtIn: false };

		if (existing >= 0) {
			customPresets[existing] = preset;
		} else {
			customPresets.push(preset);
		}

		saveCustomPresets(customPresets);
		return preset;
	}

	function loadPreset(name: string): PresetConfig | null {
		const all = getAllPresets();
		const preset = all.find((p) => p.name === name);
		return preset?.config ?? null;
	}

	function deletePreset(name: string): boolean {
		if (builtInPresets.some((p) => p.name === name)) return false;
		const idx = customPresets.findIndex((p) => p.name === name);
		if (idx < 0) return false;

		customPresets.splice(idx, 1);
		saveCustomPresets(customPresets);
		return true;
	}

	return {
		getAllPresets,
		savePreset,
		loadPreset,
		deletePreset
	};
}

export const presetStore = createPresetStore();