Add the product filter form

I need a way to search products by name in the invoice form, when the
user adds or changes a product.  Since this is something that i have to
add too to the product list, i added it now so the function will already
be ready.

pkg/products.go

@@ -8,6 +8,7 @@ import (
 	"math"
 	"net/http"
 	"strconv"
+	"strings"
 )
 
 type ProductEntry struct {
@@ -19,14 +20,21 @@ type ProductEntry struct {
 
 type productsIndexPage struct {
 	Products []*ProductEntry
+	Filters  *productFilterForm
 }
 
 func IndexProducts(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
 	conn := getConn(r)
 	company := mustGetCompany(r)
-	tag := r.URL.Query().Get("tag")
+	locale := getLocale(r)
+	filters := newProductFilterForm(locale)
+	if err := filters.Parse(r); err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
 	page := &productsIndexPage{
-		Products: mustCollectProductEntries(r.Context(), conn, company, tag),
+		Products: mustCollectProductEntries(r.Context(), conn, company, filters),
+		Filters:  filters,
 	}
 	mustRenderMainTemplate(w, r, "products/index.gohtml", page)
 }
@@ -152,8 +160,72 @@ func HandleUpdateProduct(w http.ResponseWriter, r *http.Request, params httprout
 	}
 }
 
-func mustCollectProductEntries(ctx context.Context, conn *Conn, company *Company, tag string) []*ProductEntry {
+type productFilterForm struct {
-	rows, err := conn.Query(ctx, `
+	Name          *InputField
+	Tags          *TagsField
+	TagsCondition *ToggleField
+}
+
+func newProductFilterForm(locale *Locale) *productFilterForm {
+	return &productFilterForm{
+		Name: &InputField{
+			Name:  "number",
+			Label: pgettext("input", "Invoice Number", locale),
+			Type:  "search",
+		},
+		Tags: &TagsField{
+			Name:  "tags",
+			Label: pgettext("input", "Tags", locale),
+		},
+		TagsCondition: &ToggleField{
+			Name:     "tags_condition",
+			Label:    pgettext("input", "Tags Condition", locale),
+			Selected: "and",
+			FirstOption: &ToggleOption{
+				Value:       "and",
+				Label:       pgettext("tag condition", "All", locale),
+				Description: gettext("Invoices must have all the specified labels.", locale),
+			},
+			SecondOption: &ToggleOption{
+				Value:       "or",
+				Label:       pgettext("tag condition", "Any", locale),
+				Description: gettext("Invoices must have at least one of the specified labels.", locale),
+			},
+		},
+	}
+}
+
+func (form *productFilterForm) Parse(r *http.Request) error {
+	if err := r.ParseForm(); err != nil {
+		return err
+	}
+	form.Name.FillValue(r)
+	form.Tags.FillValue(r)
+	form.TagsCondition.FillValue(r)
+	return nil
+}
+
+func mustCollectProductEntries(ctx context.Context, conn *Conn, company *Company, filters *productFilterForm) []*ProductEntry {
+	args := []interface{}{company.Id}
+	where := []string{"product.company_id = $1"}
+	appendWhere := func(expression string, value interface{}) {
+		args = append(args, value)
+		where = append(where, fmt.Sprintf(expression, len(args)))
+	}
+	if filters != nil {
+		name := strings.TrimSpace(filters.Name.String())
+		if name != "" {
+			appendWhere("product.name ilike $%d", "%"+name+"%")
+		}
+		if len(filters.Tags.Tags) > 0 {
+			if filters.TagsCondition.Selected == "and" {
+				appendWhere("product.tags @> $%d", filters.Tags)
+			} else {
+				appendWhere("product.tags && $%d", filters.Tags)
+			}
+		}
+	}
+	rows := conn.MustQuery(ctx, fmt.Sprintf(`
 		select product.slug
 		     , product.name
 		     , to_price(price, decimal_digits)
@@ -161,19 +233,15 @@ func mustCollectProductEntries(ctx context.Context, conn *Conn, company *Company
 		from product
 		join company using (company_id)
 		join currency using (currency_code)
-		where product.company_id = $1 and (($2 = '') or (tags @> array[$2]::tag_name[]))
+		where (%s)
 		order by name
-	`, company.Id, tag)
+	`, strings.Join(where, ") AND (")), args...)
-	if err != nil {
-		panic(err)
-	}
 	defer rows.Close()
 
 	var entries []*ProductEntry
 	for rows.Next() {
 		entry := &ProductEntry{}
-		err = rows.Scan(&entry.Slug, &entry.Name, &entry.Price, &entry.Tags)
+		if err := rows.Scan(&entry.Slug, &entry.Name, &entry.Price, &entry.Tags); err != nil {
-		if err != nil {
 			panic(err)
 		}
 		entries = append(entries, entry)
@@ -281,3 +349,15 @@ func (form *productForm) MustFillFromDatabase(ctx context.Context, conn *Conn, s
 		form.Tax,
 		form.Tags))
 }
+
+func HandleProductSearch(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
+	var name string
+	query := r.URL.Query()
+	for k := range query {
+		vs := query[k]
+		if len(vs) > 0 {
+			name = vs[0]
+		}
+	}
+	w.Write([]byte(name))
+}

web/template/products/index.gohtml

@@ -19,6 +19,20 @@
 
 {{ define "content" }}
     {{- /*gotype: dev.tandem.ws/tandem/numerus/pkg.productsIndexPage*/ -}}
+    <div aria-label="{{( pgettext "Filters" "title" )}}">
+        <form method="GET" action="{{ companyURI "/products"}}"
+              data-hx-target="main"
+              data-hx-boost="true"
+              data-hx-trigger="change,search,submit"
+        >
+            {{ with .Filters }}
+                {{ template "input-field" .Name }}
+                {{ template "tags-field" .Tags | addTagsAttr (print `data-conditions="` .TagsCondition.Name  `-field"`) }}
+                {{ template "toggle-field" .TagsCondition }}
+            {{ end }}
+            <button type="submit">{{( pgettext "Filter" "action" )}}</button>
+        </form>
+    </div>
     <table>
         <thead>
         <tr>
@@ -37,7 +51,7 @@
                     <td>
                         {{- range $index, $tag := .Tags }}
                             {{- if gt $index 0 }}, {{ end -}}
-                            <a href="?tag={{ . }}" data-hx-target="main" data-hx-boost="true">{{ . }}</a>
+                            <a href="?tags={{ . }}" data-hx-target="main" data-hx-boost="true">{{ . }}</a>
                         {{- end }}
                     </td>
                     <td class="numeric">{{ .Price | formatPrice }}</td>