Added PDF Generation

internal/server/api/configuration.go

@@ -18,6 +18,7 @@ func registerConfigurationRoutes(mux *http.ServeMux, configs *store.Configuratio
 	mux.HandleFunc("DELETE /configurations/{id}", deleteConfiguration(configs))
 	mux.HandleFunc("GET /configurations/{id}/preview", previewConfiguration(configs, plates, items))
 	mux.HandleFunc("GET /layout/preview", layoutPreview(plates, items))
+	registerPDFRoutes(mux, configs, plates, items)
 }
 
 type configurationResponse struct {

internal/server/api/pdf.go

@@ -0,0 +1,120 @@
+package api
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+
+	"printer.backend/internal/model"
+	"printer.backend/internal/platepdf"
+	"printer.backend/internal/store"
+)
+
+func registerPDFRoutes(mux *http.ServeMux, configs *store.ConfigurationStore, plates *store.PlateStore, items *store.ItemStore) {
+	mux.HandleFunc("GET /layout/pdf", layoutPDF(plates, items))
+	mux.HandleFunc("GET /configurations/{id}/pdf", configurationPDF(configs, plates, items))
+}
+
+func layoutPDF(plates *store.PlateStore, items *store.ItemStore) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		plateID := r.URL.Query().Get("plate_id")
+		itemID := r.URL.Query().Get("item_id")
+		if plateID == "" || itemID == "" {
+			writeError(w, http.StatusBadRequest, errors.New("plate_id and item_id query params are required"))
+			return
+		}
+		spacing, err := parseSpacing(r.URL.Query().Get("spacing_mm"))
+		if err != nil {
+			writeError(w, http.StatusBadRequest, err)
+			return
+		}
+
+		plate, item, preview, svgPath, err := resolveLayoutPDF(plates, items, plateID, itemID, spacing)
+		if err != nil {
+			writeError(w, http.StatusBadRequest, err)
+			return
+		}
+
+		pdf, err := platepdf.Generate(plate, item.Spec, svgPath, preview)
+		if err != nil {
+			writeError(w, http.StatusInternalServerError, err)
+			return
+		}
+		servePDF(w, pdf, "layout-preview.pdf")
+	}
+}
+
+func configurationPDF(configs *store.ConfigurationStore, plates *store.PlateStore, items *store.ItemStore) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id := r.PathValue("id")
+		c, err := configs.Get(id)
+		if err != nil {
+			writeError(w, http.StatusNotFound, err)
+			return
+		}
+
+		plate, item, preview, svgPath, err := resolveLayoutPDF(plates, items, c.PlateID, c.ItemID, c.SpacingMM)
+		if err != nil {
+			writeError(w, http.StatusBadRequest, err)
+			return
+		}
+
+		pdf, err := platepdf.Generate(plate, item.Spec, svgPath, preview)
+		if err != nil {
+			writeError(w, http.StatusInternalServerError, err)
+			return
+		}
+		name := c.Name
+		if name == "" {
+			name = "configuration-" + id[:8]
+		}
+		servePDF(w, pdf, sanitizeFilename(name)+".pdf")
+	}
+}
+
+func resolveLayoutPDF(plates *store.PlateStore, items *store.ItemStore, plateID, itemID string, spacingMM float64) (
+	plate model.Plate, item model.Item, preview model.LayoutPreview, svgPath string, err error,
+) {
+	plate, err = findPlate(plates, plateID)
+	if err != nil {
+		return plate, item, preview, "", err
+	}
+	item, err = items.Get(itemID)
+	if err != nil {
+		return plate, item, preview, "", err
+	}
+	svgPath, err = items.SVGPath(itemID)
+	if err != nil {
+		return plate, item, preview, "", err
+	}
+	preview, err = buildPreview(plates, items, plateID, itemID, spacingMM)
+	if err != nil {
+		return plate, item, preview, "", err
+	}
+	preview.PlateID = plateID
+	preview.ItemID = itemID
+	return plate, item, preview, svgPath, nil
+}
+
+func servePDF(w http.ResponseWriter, pdf []byte, filename string) {
+	w.Header().Set("Content-Type", "application/pdf")
+	w.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, filename))
+	w.Header().Set("Cache-Control", "no-cache")
+	_, _ = w.Write(pdf)
+}
+
+func sanitizeFilename(name string) string {
+	var b []byte
+	for i := 0; i < len(name); i++ {
+		c := name[i]
+		if (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '-' || c == '_' {
+			b = append(b, c)
+		} else if c == ' ' {
+			b = append(b, '_')
+		}
+	}
+	if len(b) == 0 {
+		return "preview"
+	}
+	return string(b)
+}