package prompt

import (
	"bytes"
	"fmt"
	"strings"
)

// RenderUserSystem renders the system and user prompt pair for promptID.
func RenderUserSystem(promptID string, data any) (system string, user string, metadata Metadata, err error) {
	trimmedID := strings.TrimSpace(promptID)
	compiled, ok := promptRegistry[trimmedID]
	if !ok {
		return "", "", Metadata{}, fmt.Errorf("unknown prompt id %q", promptID)
	}

	var systemBuf bytes.Buffer
	if err := compiled.systemTmpl.Execute(&systemBuf, data); err != nil {
		return "", "", Metadata{}, fmt.Errorf("render system prompt %q: %w", trimmedID, err)
	}

	var userBuf bytes.Buffer
	if err := compiled.userTmpl.Execute(&userBuf, data); err != nil {
		return "", "", Metadata{}, fmt.Errorf("render user prompt %q: %w", trimmedID, err)
	}

	return strings.TrimSpace(systemBuf.String()), strings.TrimSpace(userBuf.String()), compiled.metadata, nil
}