import type { FormatterFunction } from "@visulima/fmt";
import type { Meta, StringifyAwareProcessor } from "../types.d.ts";
/**
 * Message Formatter Processor.
 *
 * A processor that formats log messages using the {@link https://www.visulima.com/docs/package/fmt|@visulima/fmt} library.
 * Supports custom formatters, string interpolation, and complex object formatting.
 * Processes both the main message and contextual data.
 * @template L - The log level type
 * @example
 * ```typescript
 * import { createPail } from "@visulima/pail";
 * import MessageFormatterProcessor from "@visulima/pail/processor/message-formatter";
 *
 * const logger = createPail({
 *   processors: [new MessageFormatterProcessor({
 *     formatters: {
 *       user: (value) => `[USER:${value.id}]`
 *     }
 *   })]
 * });
 *
 * logger.info("User {user} logged in", { user: { id: 123 } });
 * // Output: "User [USER:123] logged in"
 * ```
 */
declare class MessageFormatterProcessor<L extends string = string> implements StringifyAwareProcessor<L> {
    #private;
    /**
     * Creates a new MessageFormatterProcessor instance.
     * @param options Configuration options
     * @param options.formatters Custom formatters for message interpolation
     */
    constructor(options?: {
        formatters?: Record<string, FormatterFunction>;
    });
    /**
     * Sets the stringify function for object serialization.
     * @param function_ The stringify function to use for serializing objects
     */
    setStringify(function_: any): void;
    /**
     * Processes log metadata to format messages.
     *
     * Applies string interpolation and custom formatters to the message
     * and contextual data in the log metadata.
     * @param meta The log metadata to process
     * @returns The processed metadata with formatted messages
     */
    process(meta: Meta<L>): Meta<L>;
}
export default MessageFormatterProcessor;