package tmpl

import (
	"bytes"
	"text/template"

	"github.com/Masterminds/sprig/v3"
)

func (c *Context) CreateFuncMap() template.FuncMap {
	aliased := template.FuncMap{}

	aliases := map[string]string{
		"get": "sprigGet",
	}

	funcMap := sprig.TxtFuncMap()

	for orig, alias := range aliases {
		aliased[alias] = funcMap[orig]
	}

	for name, f := range c.createFuncMap() {
		funcMap[name] = f
	}

	for name, f := range aliased {
		funcMap[name] = f
	}

	return funcMap
}

func (c *Context) newTemplate() *template.Template {
	funcMap := c.CreateFuncMap()

	tmpl := template.New("stringTemplate").Funcs(funcMap)
	if c.preRender {
		tmpl = tmpl.Option("missingkey=zero")
	} else {
		tmpl = tmpl.Option("missingkey=error")
	}
	return tmpl
}

func (c *Context) RenderTemplateToBuffer(s string, data ...any) (*bytes.Buffer, error) {
	var t, parseErr = c.newTemplate().Parse(s)
	if parseErr != nil {
		return nil, parseErr
	}

	var tplString bytes.Buffer
	var d any
	if len(data) > 0 {
		d = data[0]
	}
	var execErr = t.Execute(&tplString, d)

	if execErr != nil {
		return &tplString, execErr
	}

	return &tplString, nil
}