Added Plates and Items Models and connected them with the Frontend

internal/model/item.go

@@ -0,0 +1,25 @@
+package model
+
+import "time"
+
+// ItemSpec holds mask parameters (from template CLI).
+type ItemSpec struct {
+	SizeMM    float64 `json:"size_mm"`
+	BleedMM   float64 `json:"bleed_mm"`
+	MarginMM  float64 `json:"margin_mm"`
+	PaddingMM float64 `json:"padding_mm"`
+}
+
+// Item is a printable product type (SVG mask) placed on a plate.
+type Item struct {
+	ID          string    `json:"id"`
+	Name        string    `json:"name,omitempty"`
+	Spec        ItemSpec  `json:"spec"`
+	SVGTemplate string    `json:"svg_template"`
+	CreatedAt   time.Time `json:"created_at"`
+}
+
+// MetaFilename returns the sidecar metadata path for an SVG basename.
+func MetaFilename(svgBasename string) string {
+	return svgBasename + ".meta.json"
+}

internal/model/plate.go

@@ -0,0 +1,26 @@
+package model
+
+import "time"
+
+// Plate describes a print bed with outer dimensions and margins on each side.
+type Plate struct {
+	ID           string    `json:"id"`
+	Name         string    `json:"name,omitempty"`
+	WidthMM      float64   `json:"width_mm"`
+	HeightMM     float64   `json:"height_mm"`
+	MarginTop    float64   `json:"margin_top_mm"`
+	MarginRight  float64   `json:"margin_right_mm"`
+	MarginBottom float64   `json:"margin_bottom_mm"`
+	MarginLeft   float64   `json:"margin_left_mm"`
+	CreatedAt    time.Time `json:"created_at"`
+}
+
+// PrintableWidth returns the usable width inside the margins.
+func (p Plate) PrintableWidth() float64 {
+	return p.WidthMM - p.MarginLeft - p.MarginRight
+}
+
+// PrintableHeight returns the usable height inside the margins.
+func (p Plate) PrintableHeight() float64 {
+	return p.HeightMM - p.MarginTop - p.MarginBottom
+}