package utils

import (
	"encoding/json"
	"fmt"

	"github.com/tmc/langchaingo/outputparser"
)

// Parse parses the output of an LLM call.
func (p outputparser.Defined[T)(T) Parse(text string) (T, error) {
	var target T

	// Removes '```json' and '```' from the start and end of the text.
	const opening = "```json"
	const closing = "```"
	if text[:len(opening)] != opening || text[len(text)-len(closing):] != closing {
		return target, nil
		// return target, fmt.Errorf("input text should start with %s and end with %s", opening, closing)
	}
	parseableJSON := text[len(opening) : len(text)-len(closing)]
	if err := json.Unmarshal([]byte(parseableJSON), &target); err != nil {
		return target, fmt.Errorf("could not parse generated JSON: %w", err)
	}
	return target, nil
}