Clarify we are generating PDF's

README.md

@@ -6,10 +6,10 @@ and cataloguing system to help me keep track of what was there.
 To do that I needed to print labels for boxes, and figured it might be useful
 if they also had QR codes on them.
 
-I thought there would be a simple online tool to create pages of identical 
+I thought there would be a simple online tool to create PDF pages of identical 
 QR labels, but apparently not.
 
-# installing
+# Installing
 
     go install  code.ppl.town/justin/qr_labels/cmd/qr_labels@latest
 
@@ -38,3 +38,30 @@ borders between each label:
 
 Run `qr_labels -help` for all command line parameters.
 
+```
+Usage of qr_labels:
+  -borders
+        print borders between labels
+  -code string
+        string to turn into a QR code (URL, text etc)
+  -code-is-label
+        use the -code as the -label
+  -cols uint
+        number of columns on the page (default 3)
+  -font string
+        name of the font (default "Helvetica")
+  -font-size float
+        font-size, in pts (default 24)
+  -font-style string
+        font style, combine 'B', 'U', 'S', 'I' characters
+  -label string
+        label (printed above QR code)
+  -output string
+        filename to write the PDF
+  -page-size string
+        page size (A1, A2, A3, A4, A5, A6, A7, Letter, Legal, Tabloid) (default "A4")
+  -rows uint
+        number of rows on the page (default 4)
+  -size float
+        size of the QR code (default 50)
+```

cmd/qr_labels/main.go

@@ -18,6 +18,7 @@ var flagFontStyle string
 var flagBorders bool = true
 var flagFilename string
 var flagCodeIsLabel bool
+var flagPageSize string
 
 func main() {
 
@@ -32,6 +33,7 @@ func main() {
 	flag.StringVar(&flagFontStyle, "font-style", "", "font style, combine 'B', 'U', 'S', 'I' characters")
 	flag.BoolVar(&flagBorders, "borders", false, "print borders between labels")
 	flag.StringVar(&flagFilename, "output", "", "filename to write the PDF")
+	flag.StringVar(&flagPageSize, "page-size", "A4", "page size (A1, A2, A3, A4, A5, A6, A7, Letter, Legal, Tabloid)")
 
 	flag.BoolVar(&flagCodeIsLabel, "code-is-label", false, "use the -code as the -label")
 
@@ -69,6 +71,7 @@ func main() {
 		qr_labels.WithFont(flagFont, flagFontSize, flagFontStyle),
 		qr_labels.WithBorders(flagBorders),
 		qr_labels.WithGrid(int(flagRows), int(flagCols)),
+		qr_labels.WithPageSize(flagPageSize),
 	)
 
 	if err != nil {

qr_labels/options.go

@@ -66,3 +66,17 @@ func WithGrid(rows, cols int) optWithGrid {
 		cols: cols,
 	}
 }
+
+type optWithPageSize struct {
+	size string
+}
+
+func (o optWithPageSize) apply(po *pageOptions) {
+	po.pageSize = o.size
+}
+
+func WithPageSize(size string) optWithPageSize {
+	return optWithPageSize{
+		size: size,
+	}
+}

qr_labels/qr_labels.go

@@ -18,9 +18,12 @@ type pageOptions struct {
 	font      string
 	fontStyle string
 	fontSize  float64
-	rows      int
+
-	cols      int
+	rows     int
-	borders   bool
+	cols     int
+	pageSize string
+
+	borders bool
 }
 
 func defaultPageOptions() []Option {
@@ -29,6 +32,7 @@ func defaultPageOptions() []Option {
 		WithQRSize(40),
 		WithFont("Courier", 16.0, "B"),
 		WithGrid(4, 3),
+		WithPageSize("A4"),
 	}
 }
 
@@ -93,7 +97,7 @@ func GeneratePage(w io.Writer, url, label string, opts ...Option) error {
 	}
 	// dim := qrc.Dimension()
 
-	pdf := fpdf.New("P", "mm", "A4", "")
+	pdf := fpdf.New("P", "mm", po.pageSize, "")
 	pdf.SetMargins(0, 0, 0)
 	pageWidth, pageHeight := pdf.GetPageSize()