package html

import "html/template"

// Options are configuration options for the template service
type Options struct {
	Helpers  template.FuncMap
	PoolSize int
	DevMode  bool
}

// OptionFunc configures options for the template service
type OptionFunc func(*Options)

// WithDefaultHelpers configures the template service
// to expose the default helpers
func WithDefaultHelpers() OptionFunc {
	return func(opts *Options) {
		helpers := template.FuncMap{
			"dump":     dump,
			"ellipsis": ellipsis,
			"map":      customMap,
			"default":  defaultVal,
			"inc":      increment,
			"has":      has,
		}
		for name, fn := range helpers {
			WithHelper(name, fn)(opts)
		}
	}
}

// WithHelper configures the template service
// to expose the default helpers
func WithHelper(name string, fn interface{}) OptionFunc {
	return func(opts *Options) {
		if opts.Helpers == nil {
			opts.Helpers = make(template.FuncMap)
		}
		opts.Helpers[name] = fn
	}
}

// WithPoolSize configures the template service
// to use the given pool size
func WithPoolSize(size int) OptionFunc {
	return func(opts *Options) {
		opts.PoolSize = size
	}
}

// WithDevMode configures the template service
// to use the development mode (auto reload of templates).
func WithDevMode(enabled bool) OptionFunc {
	return func(opts *Options) {
		opts.DevMode = enabled
	}
}

func defaultOptions() *Options {
	options := &Options{}
	funcs := []OptionFunc{
		WithPoolSize(64),
		WithDefaultHelpers(),
	}
	for _, f := range funcs {
		f(options)
	}
	return options
}