/*---------------------------------------------------------
 * Copyright (C) Microsoft Corporation. All rights reserved.
 *--------------------------------------------------------*/

/**
 * A registry helper that can locate grammar file paths given scope names.
 */
export interface IGrammarLocator {
	getFilePath(scopeName:string): string;
	getInjections?(scopeName:string): string[];
}

/**
 * The registry that will hold all grammars.
 */
export class Registry {

	constructor(locator?:IGrammarLocator, useExperimentalParser?:boolean);

	/**
	 * Load the grammar for `scopeName` and all referenced included grammars asynchronously.
	 */
	public loadGrammar(scopeName:string, callback:(err:any, grammar:IGrammar)=>void): void;

	/**
	 * Load the grammar at `path` synchronously.
	 */
	public loadGrammarFromPathSync(path:string): IGrammar;

	/**
	 * Get the grammar for `scopeName`. The grammar must first be created via `loadGrammar` or `loadGrammarFromPathSync`.
	 */
	public grammarForScopeName(scopeName:string): IGrammar;
}

export interface IGrammarInfo {
	fileTypes: string[];
	name: string;
	scopeName: string;
	firstLineMatch: string;
}

/**
 * A grammar
 */
export interface IGrammar {
	/**
	 * Tokenize `lineText` using previous line state `prevState`.
	 */
	tokenizeLine(lineText: string, prevState: StackElement): ITokenizeLineResult;
}

export interface ITokenizeLineResult {
	tokens: IToken[];
	/**
	 * The `prevState` to be passed on to the next line tokenization.
	 */
	ruleStack: StackElement;
}

export interface IToken {
	startIndex: number;
	endIndex: number;
	scopes: string[];
}

/**
 * Should not be used by consumers, as its shape might change at any time.
 */
export interface StackElement {
	_stackElementBrand: void;

	equals(other:StackElement): boolean;
}