Allow optional select with empty label

This is not yet necessary, but the empty label is because i do not want to select a default tax for products—at least, not without a setting for it. Since i need to add the required attribute now to select, because otherwise the browser would allow sending that empty value, i did not want to do it unconditionally, just in case.
Convert from cents to “price” and back
2023-02-05 14:06:33 +01:00 · 2023-02-05 13:55:12 +01:00
20 changed files with 341 additions and 90 deletions
--- a/deploy/parse_price.sql
+++ b/deploy/parse_price.sql
@ -0,0 +1,47 @@
+-- Deploy numerus:parse_price to pg
+-- requires: schema_public
+
+begin;
+
+set search_path to numerus, public;
+
+create or replace function parse_price(price text, decimal_digits integer) returns integer as
+$$
+declare
+	parts text[];
+	result int;
+	frac_part text;
+begin
+	parts := string_to_array(price, '.');
+	if array_length(parts, 1) > 2 then
+		raise invalid_parameter_value using message = price || ' is not a valid price representation.';	
+	end if;
+
+	result := parts[1]::integer;
+	for d in 1..decimal_digits loop
+		result := result * 10;
+	end loop;
+
+	if array_length(parts, 1) = 2 then
+		frac_part := rtrim(parts[2], '0');
+		if length(frac_part) > decimal_digits then
+			raise invalid_parameter_value using message = price || ' has too many digits in the fraction part.';	
+		end if;
+		frac_part := rpad(frac_part, decimal_digits, '0');
+		result := result + frac_part::integer;
+	end if;
+
+	return result;
+end;
+$$
+language plpgsql
+immutable;
+
+comment on function parse_price(text, integer) is
+'Converts the string representation of a price in decimal form to cents, according to the number of decimal digits passed.';
+
+revoke execute on function parse_price(text, integer) from public;
+grant execute on function parse_price(text, integer) to invoicer;
+grant execute on function parse_price(text, integer) to admin;
+
+commit;
--- a/deploy/to_price.sql
+++ b/deploy/to_price.sql
@ -0,0 +1,28 @@
+-- Deploy numerus:to_price to pg
+-- requires: schema_numerus
+
+begin;
+
+set search_path to numerus, public;
+
+create or replace function to_price(cents integer, decimal_digits integer) returns text as
+$$
+declare
+	result text;
+	scale integer := 10^decimal_digits;
+begin
+	result = cents::text;
+	return (cents / scale)::text || '.' || to_char(mod(cents, scale), rpad('FM', decimal_digits + 2, '0'));
+end;
+$$
+language plpgsql
+immutable;
+
+comment on function to_price(integer, integer) is
+'Converts the cents to a price representation, without currency and any other separater than decimal.';
+
+revoke execute on function to_price(integer, integer) from public;
+grant execute on function to_price(integer, integer) to invoicer;
+grant execute on function to_price(integer, integer) to admin;
+
+commit;
--- a/pkg/company.go
+++ b/pkg/company.go
@ -15,8 +15,10 @@ const (
 )

 type Company struct {
-	Id   int
-	Slug string
+	Id             int
+	CurrencySymbol string
+	DecimalDigits  int
+	Slug           string
 }

 func CompanyHandler(next http.Handler) httprouter.Handle {
@ -25,7 +27,7 @@ func CompanyHandler(next http.Handler) httprouter.Handle {
 			Slug: params[0].Value,
 		}
 		conn := getConn(r)
-		err := conn.QueryRow(r.Context(), "select company_id from company where slug = $1", company.Slug).Scan(&company.Id)
+		err := conn.QueryRow(r.Context(), "select company_id, currency_symbol, decimal_digits from company join currency using (currency_code) where slug = $1", company.Slug).Scan(&company.Id, &company.CurrencySymbol, &company.DecimalDigits)
 		if err != nil {
 			http.NotFound(w, r)
 			return
@ -41,6 +43,15 @@ func CompanyHandler(next http.Handler) httprouter.Handle {
 	}
 }

+func (c Company) MinCents() float64 {
+	var r float64
+	r = 1
+	for i := 0; i < c.DecimalDigits; i++ {
+		r /= 10.0
+	}
+	return r
+}
+
 func getCompany(r *http.Request) *Company {
 	company := r.Context().Value(ContextCompanyKey)
 	if company == nil {
@ -77,6 +88,7 @@ func newTaxDetailsForm(ctx context.Context, conn *Conn, locale *Locale) *taxDeta
 			Name:     "currency",
 			Label:    pgettext("input", "Currency", locale),
 			Options:  MustGetOptions(ctx, conn, "select currency_code, currency_symbol from currency order by currency_code"),
+			Required: true,
 			Selected: "EUR",
 		},
 	}
--- a/pkg/contacts.go
+++ b/pkg/contacts.go
@ -224,6 +224,7 @@ func newContactForm(ctx context.Context, conn *Conn, locale *Locale) *contactFor
 			Name:     "country",
 			Label:    pgettext("input", "Tax", locale),
 			Options:  mustGetCountryOptions(ctx, conn, locale),
+			Required: true,
 			Selected: "ES",
 			Attributes: []template.HTMLAttr{
 				`autocomplete="country"`,
--- a/pkg/form.go
+++ b/pkg/form.go
@ -61,6 +61,8 @@ type SelectField struct {
 	Selected   string
 	Options    []*SelectOption
 	Attributes []template.HTMLAttr
+	Required   bool
+	EmptyLabel string
 	Errors     []error
 }

@ -175,6 +177,11 @@ func (v *FormValidator) CheckValidInteger(field *InputField, min int, max int, m
 	return v.checkInput(field, err == nil && value >= min && value <= max, message)
 }

+func (v *FormValidator) CheckValidDecimal(field *InputField, min float64, max float64, message string) bool {
+	value, err := strconv.ParseFloat(field.Val, 64)
+	return v.checkInput(field, err == nil && value >= min && value <= max, message)
+}
+
 func (v *FormValidator) checkInput(field *InputField, ok bool, message string) bool {
 	if !ok {
 		field.Errors = append(field.Errors, errors.New(message))
--- a/pkg/products.go
+++ b/pkg/products.go
@ -2,6 +2,7 @@ package pkg

 import (
 	"context"
+	"fmt"
 	"github.com/jackc/pgx/v4"
 	"github.com/julienschmidt/httprouter"
 	"html/template"
@ -12,7 +13,7 @@ import (
 type ProductEntry struct {
 	Slug  string
 	Name  string
-	Price int
+	Price string
 }

 type productsIndexPage struct {
@ -35,11 +36,12 @@ func GetProductForm(w http.ResponseWriter, r *http.Request, params httprouter.Pa
 	form := newProductForm(r.Context(), conn, locale, company)
 	slug := params[0].Value
 	if slug == "new" {
+		form.Tax.EmptyLabel = gettext("Select a tax for this product.", locale)
 		w.WriteHeader(http.StatusOK)
 		mustRenderNewProductForm(w, r, form)
 		return
 	}
-	err := conn.QueryRow(r.Context(), "select name, description, price, tax_id from product where slug = $1", slug).Scan(form.Name, form.Description, form.Price, form.Tax)
+	err := conn.QueryRow(r.Context(), "select product.name, product.description, to_price(price, decimal_digits), tax_id from product join company using (company_id) join currency using (currency_code) where product.slug = $1", slug).Scan(form.Name, form.Description, form.Price, form.Tax)
 	if err != nil {
 		if err == pgx.ErrNoRows {
 			http.NotFound(w, r)
@ -77,7 +79,7 @@ func HandleAddProduct(w http.ResponseWriter, r *http.Request, _ httprouter.Param
 		mustRenderNewProductForm(w, r, form)
 		return
 	}
-	conn.MustExec(r.Context(), "insert into product (company_id, name, description, price, tax_id) values ($1, $2, $3, $4, $5)", company.Id, form.Name, form.Description, form.Price, form.Tax)
+	conn.MustExec(r.Context(), "insert into product (company_id, name, description, price, tax_id) select company_id, $2, $3, parse_price($4, decimal_digits), $5 from company join currency using (currency_code) where company_id = $1", company.Id, form.Name, form.Description, form.Price, form.Tax)
 	http.Redirect(w, r, companyURI(company, "/products"), http.StatusSeeOther)
 }

@ -98,7 +100,7 @@ func HandleUpdateProduct(w http.ResponseWriter, r *http.Request, params httprout
 		mustRenderEditProductForm(w, r, form)
 		return
 	}
-	slug := conn.MustGetText(r.Context(), "", "update product set name = $1, description = $2, price = $3, tax_id = $4 where slug = $5 returning slug", form.Name, form.Description, form.Price, form.Tax, params[0].Value)
+	slug := conn.MustGetText(r.Context(), "", "update product set name = $1, description = $2, price = parse_price($3, decimal_digits), tax_id = $4 from company join currency using (currency_code) where product.company_id = company.company_id and product.slug = $5 returning product.slug", form.Name, form.Description, form.Price, form.Tax, params[0].Value)
 	if slug == "" {
 		http.NotFound(w, r)
 	}
@ -106,7 +108,7 @@ func HandleUpdateProduct(w http.ResponseWriter, r *http.Request, params httprout
 }

 func mustGetProductEntries(ctx context.Context, conn *Conn, company *Company) []*ProductEntry {
-	rows, err := conn.Query(ctx, "select slug, name, price from product where company_id = $1 order by name", company.Id)
+	rows, err := conn.Query(ctx, "select product.slug, product.name, to_price(price, decimal_digits) from product join company using (company_id) join currency using (currency_code) where company_id = $1 order by name", company.Id)
 	if err != nil {
 		panic(err)
 	}
@ -130,6 +132,7 @@ func mustGetProductEntries(ctx context.Context, conn *Conn, company *Company) []

 type productForm struct {
 	locale      *Locale
+	company     *Company
 	Name        *InputField
 	Description *InputField
 	Price       *InputField
@ -138,7 +141,8 @@ type productForm struct {

 func newProductForm(ctx context.Context, conn *Conn, locale *Locale, company *Company) *productForm {
 	return &productForm{
-		locale: locale,
+		locale:  locale,
+		company: company,
 		Name: &InputField{
 			Name:     "name",
 			Label:    pgettext("input", "Name", locale),
@ -157,12 +161,14 @@ func newProductForm(ctx context.Context, conn *Conn, locale *Locale, company *Co
 			Required: true,
 			Attributes: []template.HTMLAttr{
 				`min="0"`,
+				template.HTMLAttr(fmt.Sprintf(`step="%v"`, company.MinCents())),
 			},
 		},
 		Tax: &SelectField{
-			Name:    "tax",
-			Label:   pgettext("input", "Tax", locale),
-			Options: MustGetOptions(ctx, conn, "select tax_id::text, name from tax where company_id = $1 order by name", company.Id),
+			Name:     "tax",
+			Label:    pgettext("input", "Tax", locale),
+			Required: true,
+			Options:  MustGetOptions(ctx, conn, "select tax_id::text, name from tax where company_id = $1 order by name", company.Id),
 		},
 	}
 }
@ -182,7 +188,7 @@ func (form *productForm) Validate() bool {
 	validator := newFormValidator()
 	validator.CheckRequiredInput(form.Name, gettext("Name can not be empty.", form.locale))
 	if validator.CheckRequiredInput(form.Price, gettext("Price can not be empty.", form.locale)) {
-		validator.CheckValidInteger(form.Price, 0, math.MaxInt, gettext("Price must be a number greater than zero.", form.locale))
+		validator.CheckValidDecimal(form.Price, form.company.MinCents(), math.MaxFloat64, gettext("Price must be a number greater than zero.", form.locale))
 	}
 	validator.CheckValidSelectOption(form.Tax, gettext("Selected tax is not valid.", form.locale))
 	return validator.AllOK()
--- a/pkg/profile.go
+++ b/pkg/profile.go
@ -61,9 +61,10 @@ func newProfileForm(ctx context.Context, conn *Conn, locale *Locale) *profileFor
 			},
 		},
 		Language: &SelectField{
-			Name:    "language",
-			Label:   pgettext("input", "Language", locale),
-			Options: languages,
+			Name:     "language",
+			Label:    pgettext("input", "Language", locale),
+			Options:  languages,
+			Required: true,
 			Attributes: []template.HTMLAttr{
 				`autocomplete="language"`,
 			},
--- a/pkg/template.go
+++ b/pkg/template.go
@ -2,9 +2,13 @@ package pkg

 import (
 	"fmt"
+	"golang.org/x/text/message"
+	"golang.org/x/text/number"
 	"html/template"
 	"io"
+	"math"
 	"net/http"
+	"strconv"
 )

 const overrideMethodName = "_method"
@ -27,6 +31,14 @@ func mustRenderTemplate(wr io.Writer, r *http.Request, layout string, filename s
 		"companyURI": func(uri string) string {
 			return companyURI(company, uri)
 		},
+		"formatPrice": func(price string) string {
+			p := message.NewPrinter(locale.Language)
+			f, err := strconv.ParseFloat(price, 64)
+			if err != nil {
+				f = math.NaN()
+			}
+			return p.Sprintf("%.*f", company.DecimalDigits, number.Decimal(f))
+		},
 		"csrfToken": func() template.HTML {
 			return template.HTML(fmt.Sprintf(`<input type="hidden" name="%s" value="%s">`, csrfTokenField, user.CsrfToken))
 		},
--- a/po/ca.po
+++ b/po/ca.po
@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: numerus\n"
 "Report-Msgid-Bugs-To: jordi@tandem.blog\n"
-"POT-Creation-Date: 2023-02-04 11:24+0100\n"
+"POT-Creation-Date: 2023-02-05 14:04+0100\n"
 "PO-Revision-Date: 2023-01-18 17:08+0100\n"
 "Last-Translator: jordi fita mas <jordi@tandem.blog>\n"
 "Language-Team: Catalan <ca@dodds.net>\n"
@ -238,11 +238,11 @@ msgctxt "input"
 msgid "Password"
 msgstr "Contrasenya"

-#: pkg/login.go:69 pkg/profile.go:88 pkg/contacts.go:262
+#: pkg/login.go:69 pkg/profile.go:89 pkg/contacts.go:263
 msgid "Email can not be empty."
 msgstr "No podeu deixar el correu-e en blanc."

-#: pkg/login.go:70 pkg/profile.go:89 pkg/contacts.go:263
+#: pkg/login.go:70 pkg/profile.go:90 pkg/contacts.go:264
 msgid "This value is not a valid email. It should be like name@domain.com."
 msgstr "Aquest valor no és un correu-e vàlid. Hauria de ser similar a nom@domini.cat."

@ -254,70 +254,74 @@ msgstr "No podeu deixar la contrasenya en blanc."
 msgid "Invalid user or password."
 msgstr "Nom d’usuari o contrasenya incorrectes."

-#: pkg/products.go:144
+#: pkg/products.go:39
+msgid "Select a tax for this product."
+msgstr "Escolliu un impost per aquest producte."
+
+#: pkg/products.go:148
 msgctxt "input"
 msgid "Name"
 msgstr "Nom"

-#: pkg/products.go:150
+#: pkg/products.go:154
 msgctxt "input"
 msgid "Description"
 msgstr "Descripció"

-#: pkg/products.go:155
+#: pkg/products.go:159
 msgctxt "input"
 msgid "Price"
 msgstr "Preu"

-#: pkg/products.go:164 pkg/contacts.go:225
+#: pkg/products.go:169 pkg/contacts.go:225
 msgctxt "input"
 msgid "Tax"
 msgstr "Impost"

-#: pkg/products.go:183 pkg/profile.go:91
+#: pkg/products.go:189 pkg/profile.go:92
 msgid "Name can not be empty."
 msgstr "No podeu deixar el nom en blanc."

-#: pkg/products.go:184
+#: pkg/products.go:190
 msgid "Price can not be empty."
 msgstr "No podeu deixar el preu en blanc."

-#: pkg/products.go:185
+#: pkg/products.go:191
 msgid "Price must be a number greater than zero."
 msgstr "El preu ha de ser un número major a zero."

-#: pkg/products.go:187
+#: pkg/products.go:193
 msgid "Selected tax is not valid."
 msgstr "Heu seleccionat un impost que no és vàlid."

-#: pkg/company.go:78
+#: pkg/company.go:89
 msgctxt "input"
 msgid "Currency"
 msgstr "Moneda"

-#: pkg/company.go:95
+#: pkg/company.go:107
 msgid "Selected currency is not valid."
 msgstr "Heu seleccionat una moneda que no és vàlida."

-#: pkg/company.go:217
+#: pkg/company.go:229
 msgctxt "input"
 msgid "Tax name"
 msgstr "Nom impost"

-#: pkg/company.go:223
+#: pkg/company.go:235
 msgctxt "input"
 msgid "Rate (%)"
 msgstr "Percentatge"

-#: pkg/company.go:245
+#: pkg/company.go:257
 msgid "Tax name can not be empty."
 msgstr "No podeu deixar el nom de l’impost en blanc."

-#: pkg/company.go:246
+#: pkg/company.go:258
 msgid "Tax rate can not be empty."
 msgstr "No podeu deixar percentatge en blanc."

-#: pkg/company.go:247
+#: pkg/company.go:259
 msgid "Tax rate must be an integer between -99 and 99."
 msgstr "El percentatge ha de ser entre -99 i 99."

@ -341,11 +345,11 @@ msgctxt "input"
 msgid "Language"
 msgstr "Idioma"

-#: pkg/profile.go:92
+#: pkg/profile.go:93
 msgid "Confirmation does not match password."
 msgstr "La confirmació no és igual a la contrasenya."

-#: pkg/profile.go:93
+#: pkg/profile.go:94
 msgid "Selected language is not valid."
 msgstr "Heu seleccionat un idioma que no és vàlid."

@ -394,51 +398,51 @@ msgctxt "input"
 msgid "Postal code"
 msgstr "Codi postal"

-#: pkg/contacts.go:255
+#: pkg/contacts.go:256
 msgid "Business name can not be empty."
 msgstr "No podeu deixar el nom i els cognoms en blanc."

-#: pkg/contacts.go:256
+#: pkg/contacts.go:257
 msgid "VAT number can not be empty."
 msgstr "No podeu deixar el DNI o NIF en blanc."

-#: pkg/contacts.go:257
+#: pkg/contacts.go:258
 msgid "This value is not a valid VAT number."
 msgstr "Aquest valor no és un DNI o NIF vàlid."

-#: pkg/contacts.go:259
+#: pkg/contacts.go:260
 msgid "Phone can not be empty."
 msgstr "No podeu deixar el telèfon en blanc."

-#: pkg/contacts.go:260
+#: pkg/contacts.go:261
 msgid "This value is not a valid phone number."
 msgstr "Aquest valor no és un telèfon vàlid."

-#: pkg/contacts.go:266
+#: pkg/contacts.go:267
 msgid "This value is not a valid web address. It should be like https://domain.com/."
 msgstr "Aquest valor no és una adreça web vàlida. Hauria de ser similar a https://domini.cat/."

-#: pkg/contacts.go:268
+#: pkg/contacts.go:269
 msgid "Address can not be empty."
 msgstr "No podeu deixar l’adreça en blanc."

-#: pkg/contacts.go:269
+#: pkg/contacts.go:270
 msgid "City can not be empty."
 msgstr "No podeu deixar la població en blanc."

-#: pkg/contacts.go:270
+#: pkg/contacts.go:271
 msgid "Province can not be empty."
 msgstr "No podeu deixar la província en blanc."

-#: pkg/contacts.go:271
+#: pkg/contacts.go:272
 msgid "Postal code can not be empty."
 msgstr "No podeu deixar el codi postal en blanc."

-#: pkg/contacts.go:272
+#: pkg/contacts.go:273
 msgid "This value is not a valid postal code."
 msgstr "Aquest valor no és un codi postal vàlid."

-#: pkg/contacts.go:274
+#: pkg/contacts.go:275
 msgid "Selected country is not valid."
 msgstr "Heu seleccionat un país que no és vàlid."

--- a/po/es.po
+++ b/po/es.po
@ -7,7 +7,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: numerus\n"
 "Report-Msgid-Bugs-To: jordi@tandem.blog\n"
-"POT-Creation-Date: 2023-02-04 11:24+0100\n"
+"POT-Creation-Date: 2023-02-05 14:04+0100\n"
 "PO-Revision-Date: 2023-01-18 17:45+0100\n"
 "Last-Translator: jordi fita mas <jordi@tandem.blog>\n"
 "Language-Team: Spanish <es@tp.org.es>\n"
@ -238,11 +238,11 @@ msgctxt "input"
 msgid "Password"
 msgstr "Contraseña"

-#: pkg/login.go:69 pkg/profile.go:88 pkg/contacts.go:262
+#: pkg/login.go:69 pkg/profile.go:89 pkg/contacts.go:263
 msgid "Email can not be empty."
 msgstr "No podéis dejar el correo-e en blanco."

-#: pkg/login.go:70 pkg/profile.go:89 pkg/contacts.go:263
+#: pkg/login.go:70 pkg/profile.go:90 pkg/contacts.go:264
 msgid "This value is not a valid email. It should be like name@domain.com."
 msgstr "Este valor no es un correo-e válido. Tiene que ser parecido a nombre@dominio.es."

@ -254,70 +254,74 @@ msgstr "No podéis dejar la contraseña en blanco."
 msgid "Invalid user or password."
 msgstr "Nombre de usuario o contraseña inválido."

-#: pkg/products.go:144
+#: pkg/products.go:39
+msgid "Select a tax for this product."
+msgstr "Escoged un impuesto para este producto."
+
+#: pkg/products.go:148
 msgctxt "input"
 msgid "Name"
 msgstr "Nombre"

-#: pkg/products.go:150
+#: pkg/products.go:154
 msgctxt "input"
 msgid "Description"
 msgstr "Descripción"

-#: pkg/products.go:155
+#: pkg/products.go:159
 msgctxt "input"
 msgid "Price"
 msgstr "Precio"

-#: pkg/products.go:164 pkg/contacts.go:225
+#: pkg/products.go:169 pkg/contacts.go:225
 msgctxt "input"
 msgid "Tax"
 msgstr "Impuesto"

-#: pkg/products.go:183 pkg/profile.go:91
+#: pkg/products.go:189 pkg/profile.go:92
 msgid "Name can not be empty."
 msgstr "No podéis dejar el nombre en blanco."

-#: pkg/products.go:184
+#: pkg/products.go:190
 msgid "Price can not be empty."
 msgstr "No podéis dejar el precio en blanco."

-#: pkg/products.go:185
+#: pkg/products.go:191
 msgid "Price must be a number greater than zero."
 msgstr "El precio tiene que ser un número mayor a cero."

-#: pkg/products.go:187
+#: pkg/products.go:193
 msgid "Selected tax is not valid."
 msgstr "Habéis escogido un impuesto que no es válido."

-#: pkg/company.go:78
+#: pkg/company.go:89
 msgctxt "input"
 msgid "Currency"
 msgstr "Moneda"

-#: pkg/company.go:95
+#: pkg/company.go:107
 msgid "Selected currency is not valid."
 msgstr "Habéis escogido una moneda que no es válida."

-#: pkg/company.go:217
+#: pkg/company.go:229
 msgctxt "input"
 msgid "Tax name"
 msgstr "Nombre impuesto"

-#: pkg/company.go:223
+#: pkg/company.go:235
 msgctxt "input"
 msgid "Rate (%)"
 msgstr "Porcentaje"

-#: pkg/company.go:245
+#: pkg/company.go:257
 msgid "Tax name can not be empty."
 msgstr "No podéis dejar el nombre del impuesto en blanco."

-#: pkg/company.go:246
+#: pkg/company.go:258
 msgid "Tax rate can not be empty."
 msgstr "No podéis dejar el porcentaje en blanco."

-#: pkg/company.go:247
+#: pkg/company.go:259
 msgid "Tax rate must be an integer between -99 and 99."
 msgstr "El porcentaje tiene que estar entre -99 y 99."

@ -341,11 +345,11 @@ msgctxt "input"
 msgid "Language"
 msgstr "Idioma"

-#: pkg/profile.go:92
+#: pkg/profile.go:93
 msgid "Confirmation does not match password."
 msgstr "La confirmación no corresponde con la contraseña."

-#: pkg/profile.go:93
+#: pkg/profile.go:94
 msgid "Selected language is not valid."
 msgstr "Habéis escogido un idioma que no es válido."

@ -394,51 +398,51 @@ msgctxt "input"
 msgid "Postal code"
 msgstr "Código postal"

-#: pkg/contacts.go:255
+#: pkg/contacts.go:256
 msgid "Business name can not be empty."
 msgstr "No podéis dejar el nombre y los apellidos en blanco."

-#: pkg/contacts.go:256
+#: pkg/contacts.go:257
 msgid "VAT number can not be empty."
 msgstr "No podéis dejar el DNI o NIF en blanco."

-#: pkg/contacts.go:257
+#: pkg/contacts.go:258
 msgid "This value is not a valid VAT number."
 msgstr "Este valor no es un DNI o NIF válido."

-#: pkg/contacts.go:259
+#: pkg/contacts.go:260
 msgid "Phone can not be empty."
 msgstr "No podéis dejar el teléfono en blanco."

-#: pkg/contacts.go:260
+#: pkg/contacts.go:261
 msgid "This value is not a valid phone number."
 msgstr "Este valor no es un teléfono válido."

-#: pkg/contacts.go:266
+#: pkg/contacts.go:267
 msgid "This value is not a valid web address. It should be like https://domain.com/."
 msgstr "Este valor no es una dirección web válida. Tiene que ser parecida a https://dominio.es/."

-#: pkg/contacts.go:268
+#: pkg/contacts.go:269
 msgid "Address can not be empty."
 msgstr "No podéis dejar la dirección en blanco."

-#: pkg/contacts.go:269
+#: pkg/contacts.go:270
 msgid "City can not be empty."
 msgstr "No podéis dejar la población en blanco."

-#: pkg/contacts.go:270
+#: pkg/contacts.go:271
 msgid "Province can not be empty."
 msgstr "No podéis dejar la provincia en blanco."

-#: pkg/contacts.go:271
+#: pkg/contacts.go:272
 msgid "Postal code can not be empty."
 msgstr "No podéis dejar el código postal en blanco."

-#: pkg/contacts.go:272
+#: pkg/contacts.go:273
 msgid "This value is not a valid postal code."
 msgstr "Este valor no es un código postal válido válido."

-#: pkg/contacts.go:274
+#: pkg/contacts.go:275
 msgid "Selected country is not valid."
 msgstr "Habéis escogido un país que no es válido."

--- a/revert/parse_price.sql
+++ b/revert/parse_price.sql
@ -0,0 +1,7 @@
+-- Revert numerus:parse_price from pg
+
+begin;
+
+drop function if exists numerus.parse_price(text, integer);
+
+commit;
--- a/revert/to_price.sql
+++ b/revert/to_price.sql
@ -0,0 +1,7 @@
+-- Revert numerus:to_price from pg
+
+begin;
+
+drop function if exists numerus.to_price(integer, integer);
+
+commit;
--- a/sqitch.plan
+++ b/sqitch.plan
@ -40,3 +40,5 @@ tax_rate [schema_numerus] 2023-01-28T11:33:39Z jordi fita mas <jordi@tandem.blog
 tax [schema_numerus company tax_rate] 2023-01-28T11:45:47Z jordi fita mas <jordi@tandem.blog> # Add relation for taxes
 contact [schema_numerus company extension_vat email extension_pg_libphonenumber extension_uri currency_code currency country_code country] 2023-01-29T12:59:18Z jordi fita mas <jordi@tandem.blog> # Add the relation for contacts
 product [schema_numerus company] 2023-02-04T09:17:24Z jordi fita mas <jordi@tandem.blog> # Add relation for products
+parse_price [schema_public] 2023-02-05T11:04:54Z jordi fita mas <jordi@tandem.blog> # Add function to convert from price to cents
+to_price [schema_numerus] 2023-02-05T11:46:31Z jordi fita mas <jordi@tandem.blog> # Add function to format cents to prices
--- a/test/parse_price.sql
+++ b/test/parse_price.sql
@ -0,0 +1,53 @@
+-- Test parse_price
+set client_min_messages to warning;
+create extension if not exists pgtap;
+reset client_min_messages;
+
+begin;
+
+select plan(36);
+
+set search_path to auth, numerus, public;
+
+select has_function('numerus', 'parse_price', array ['text', 'integer']);
+select function_lang_is('numerus', 'parse_price', array ['text', 'integer'], 'plpgsql');
+select function_returns('numerus', 'parse_price', array ['text', 'integer'], 'integer');
+select isnt_definer('numerus', 'parse_price', array ['text', 'integer']);
+select volatility_is('numerus', 'parse_price', array ['text', 'integer'], 'immutable');
+select function_privs_are('numerus', 'parse_price', array ['text', 'integer'], 'guest', array []::text[]);
+select function_privs_are('numerus', 'parse_price', array ['text', 'integer'], 'invoicer', array ['EXECUTE']);
+select function_privs_are('numerus', 'parse_price', array ['text', 'integer'], 'admin', array ['EXECUTE']);
+select function_privs_are('numerus', 'parse_price', array ['text', 'integer'], 'authenticator', array []::text[]);
+
+select is( parse_price('1.1', 2), 110 );
+select is( parse_price('1.1', 3), 1100 );
+select is( parse_price('0', 2), 0 );
+select is( parse_price('0', 3), 0 );
+select is( parse_price('0.01', 2), 1 );
+select is( parse_price('0.001', 3), 1 );
+select is( parse_price('0.1', 2), 10 );
+select is( parse_price('0.01', 3), 10 );
+select is( parse_price('1', 2), 100 );
+select is( parse_price('0.1', 3), 100 );
+select is( parse_price('10', 2), 1000 );
+select is( parse_price('1', 3), 1000 );
+select is( parse_price('23.23', 2), 2323 );
+select is( parse_price('23.23', 3), 23230 );
+select throws_ok( $$ select parse_price('234.234', 2) $$ );
+select is( parse_price('234.234', 3), 234234 );
+select throws_ok( $$ select parse_price('2345.2345', 2) $$ );
+select throws_ok( $$ select parse_price('2345.2345', 3) $$ );
+select is( parse_price('00000000000000001.100000000000000000000', 2), 110 );
+select is( parse_price('00000000000000001.100000000000000000000', 3), 1100 );
+select is( parse_price('00000000000000000.100000000000000000000', 2), 10 );
+select is( parse_price('00000000000000000.100000000000000000000', 3), 100 );
+select is( parse_price('00000000000123456.780000000000000000000', 2), 12345678 );
+select is( parse_price('00000000000123456.789000000000000000000', 3), 123456789 );
+select throws_ok( $$ select parse_price('1,1', 2) $$ );
+select throws_ok( $$ select parse_price('1.1.1', 2) $$ );
+select throws_ok( $$ select parse_price('a.b', 2) $$ );
+
+select *
+from finish();
+
+rollback;
--- a/test/to_price.sql
+++ b/test/to_price.sql
@ -0,0 +1,40 @@
+-- Test to_price
+set client_min_messages to warning;
+create extension if not exists pgtap;
+reset client_min_messages;
+
+begin;
+
+select plan(23);
+
+set search_path to numerus, public;
+
+select has_function('numerus', 'to_price', array ['integer', 'integer']);
+select function_lang_is('numerus', 'to_price', array ['integer', 'integer'], 'plpgsql');
+select function_returns('numerus', 'to_price', array ['integer', 'integer'], 'text');
+select isnt_definer('numerus', 'to_price', array ['integer', 'integer']);
+select volatility_is('numerus', 'to_price', array ['integer', 'integer'], 'immutable');
+select function_privs_are('numerus', 'to_price', array ['integer', 'integer'], 'guest', array []::text[]);
+select function_privs_are('numerus', 'to_price', array ['integer', 'integer'], 'invoicer', array ['EXECUTE']);
+select function_privs_are('numerus', 'to_price', array ['integer', 'integer'], 'admin', array ['EXECUTE']);
+select function_privs_are('numerus', 'to_price', array ['integer', 'integer'], 'authenticator', array []::text[]);
+
+select is( to_price(0, 2), '0.00' );
+select is( to_price(0, 3), '0.000' );
+select is( to_price(1, 2), '0.01' );
+select is( to_price(1, 3), '0.001' );
+select is( to_price(10, 2), '0.10' );
+select is( to_price(10, 3), '0.010' );
+select is( to_price(100, 2), '1.00' );
+select is( to_price(100, 3), '0.100' );
+select is( to_price(110, 2), '1.10' );
+select is( to_price(1100, 3), '1.100' );
+select is( to_price(12345678, 2), '123456.78' );
+select is( to_price(12345678, 3), '12345.678' );
+select is( to_price(12345678, 4), '1234.5678' );
+select is( to_price(12345678, 5), '123.45678' );
+
+select *
+from finish();
+
+rollback;
--- a/verify/parse_price.sql
+++ b/verify/parse_price.sql
@ -0,0 +1,7 @@
+-- Verify numerus:parse_price on pg
+
+begin;
+
+select has_function_privilege('numerus.parse_price(text, integer)', 'execute');
+
+rollback;
--- a/verify/to_price.sql
+++ b/verify/to_price.sql
@ -0,0 +1,7 @@
+-- Verify numerus:to_price on pg
+
+begin;
+
+select has_function_privilege('numerus.to_price(integer, integer)', 'execute');
+
+rollback;
--- a/web/static/numerus.css
+++ b/web/static/numerus.css
@ -342,11 +342,13 @@ input.width-2x {
    color: var(--numerus--color--red);
 }

-[lang="en"] input:not([required]) + label::after {
+[lang="en"] input:not([required]) + label::after,
+[lang="en"] select:not([required]) + label::after {
    content: " (optional)"
 }

-[lang="ca"] input:not([required]) + label::after, [lang="es"] input:not([required]) + label::after {
+[lang="ca"] input:not([required]) + label::after, [lang="es"] input:not([required]) + label::after,
+[lang="ca"] select:not([required]) + label::after, [lang="es"] select:not([required]) + label::after {
    content: " (opcional)"
 }

--- a/web/template/form.gohtml
+++ b/web/template/form.gohtml
@ -1,8 +1,8 @@
 {{ define "input-field" -}}
    <div class="input {{ if .Errors }}has-errors{{ end }}">
        <input type="{{ .Type }}" name="{{ .Name }}" id="{{ .Name }}-field"
-        {{- range $attribute := .Attributes }} {{$attribute}} {{ end }}
-        {{ if .Required }}required="required"{{ end }} value="{{ .Val }}" placeholder="{{ .Label }}">
+                {{- range $attribute := .Attributes }} {{$attribute}} {{ end }}
+                {{ if .Required }}required="required"{{ end }} value="{{ .Val }}" placeholder="{{ .Label }}">
        <label for="{{ .Name }}-field">{{ .Label }}</label>
        {{- if .Errors }}
            <ul>
@ -17,12 +17,16 @@
 {{ define "select-field" -}}
    <div class="input {{ if .Errors }}has-errors{{ end }}">
        <select id="{{ .Name }}-field" name="{{ .Name }}"
-        {{- range $attribute := .Attributes }} {{$attribute}} {{ end -}}
+                {{- range $attribute := .Attributes }} {{$attribute}} {{ end -}}
+                {{ if .Required }}required="required"{{ end }}
        >
-        {{- range $option := .Options }}
-            <option value="{{ .Value }}"
-                    {{- if eq .Value $.Selected }} selected="selected"{{ end }}>{{ .Label }}</option>
-        {{- end }}
+            {{- with .EmptyLabel }}
+                <option value="">{{ . }}</option>
+            {{- end}}
+            {{- range $option := .Options }}
+                <option value="{{ .Value }}"
+                        {{- if eq .Value $.Selected }} selected="selected"{{ end }}>{{ .Label }}</option>
+            {{- end }}
        </select>
        <label for="{{ .Name }}-field">{{ .Label }}</label>
        {{- if .Errors }}
--- a/web/template/products/index.gohtml
+++ b/web/template/products/index.gohtml
@ -29,7 +29,7 @@
                <tr>
                    <td></td>
                    <td><a href="{{ companyURI "/products/"}}{{ .Slug }}">{{ .Name }}</a></td>
-                    <td>{{ .Price }}</td>
+                    <td>{{ .Price | formatPrice }}</td>
                </tr>
            {{- end }}
        {{ else }}