package database

import (
	"bytes"
	"fmt"
	"strings"
	"sync"
	"text/template"
)

var queriesCache sync.Map

func BuildQuery(text string, data map[string]interface{}) (string, []interface{}, error) {
	var t *template.Template
	v, ok := queriesCache.Load(text)
	if !ok {
		var err error
		t, err = template.New("query").Parse(text)
		if err != nil {
			return "", nil, fmt.Errorf("could not parse sql query template: %w", err)
		}

		queriesCache.Store(text, t)
	} else {
		t = v.(*template.Template)
	}

	var wr bytes.Buffer
	if err := t.Execute(&wr, data); err != nil {
		return "", nil, fmt.Errorf("could not apply sql query data: %w", err)
	}

	query := wr.String()
	var args []interface{}
	for key, val := range data {
		if !strings.Contains(query, "@"+key) {
			continue
		}

		args = append(args, val)
		query = strings.Replace(query, "@"+key, fmt.Sprintf("$%d", len(args)), -1)
	}
	return query, args, nil
}