Issue #121 Add Last Page information FooterFnc

3 files changed, 88 insertions, 3 deletions

diff --git a/def.go b/def.go
index c80eb37..ecc700b 100644
--- a/def.go
+++ b/def.go
@@ -221,6 +221,7 @@ type Fpdf struct {
 	headerFnc        func()                    // function provided by app and called to write header
 	inFooter         bool                      // flag set when processing footer
 	footerFnc        func()                    // function provided by app and called to write footer
+	footerFncLpi     func(bool)                // this same with footerFnc with additioanl info to indicates last page
 	zoomMode         string                    // zoom display mode
 	layoutMode       string                    // layout display mode
 	title            string                    // title
diff --git a/fpdf.go b/fpdf.go
index 9587e55..2c7e993 100644
--- a/fpdf.go
+++ b/fpdf.go
@@ -366,10 +366,17 @@ func (f *Fpdf) SetHeaderFunc(fnc func()) {
 // access to the Fpdf instance and other document generation variables.
 //
 // This method is demonstrated in the example for AddPage().
+// Deprecated: Use SetFooterFuncLpi instead.
 func (f *Fpdf) SetFooterFunc(fnc func()) {
 	f.footerFnc = fnc
 }
 
+// SetFooterFuncLpi work like SetFooterFnc it's just add Last Page information,
+// true mean this is the last page.
+func (f *Fpdf) SetFooterFuncLpi(fnc func(bool)) {
+	f.footerFncLpi = fnc
+}
+
 // SetTopMargin defines the top margin. The method can be called before
 // creating the first page.
 func (f *Fpdf) SetTopMargin(margin float64) {
@@ -538,11 +545,19 @@ func (f *Fpdf) Close() {
 		}
 	}
 	// Page footer
-	if f.footerFnc != nil {
+	if f.footerFnc != nil && f.footerFncLpi == nil {
 		f.inFooter = true
 		f.footerFnc()
 		f.inFooter = false
 	}
+
+	// Page footer
+	if f.footerFncLpi != nil {
+		f.inFooter = true
+		f.footerFncLpi(true) // Last Page.
+		f.inFooter = false
+	}
+
 	// Close page
 	f.endpage()
 	// Close document
@@ -592,11 +607,17 @@ func (f *Fpdf) AddPageFormat(orientationStr string, size SizeType) {
 	tc := f.color.text
 	cf := f.colorFlag
 	if f.page > 0 {
-		// Page footer
-		if f.footerFnc != nil {
+		// Page footer avoid double call on footer.
+		if f.footerFnc != nil && f.footerFncLpi == nil {
 			f.inFooter = true
 			f.footerFnc()
 			f.inFooter = false
+
+		}
+		if f.footerFncLpi != nil {
+			f.inFooter = true
+			f.footerFncLpi(false) //not last page.
+			f.inFooter = false
 		}
 		// Close page
 		f.endpage()
diff --git a/fpdf_test.go b/fpdf_test.go
index 7da45aa..f25866e 100644
--- a/fpdf_test.go
+++ b/fpdf_test.go
@@ -75,7 +75,70 @@ func TestIssue0116(t *testing.T) {
 	if pdf.Error() == nil {
 		t.Fatalf("expecting error when rendering text without having set font")
 	}
+}
+
+// Test to make sure the footer is not call twice and SetFooterFuncLpi can work
+// without SetFooterFunc.
+func TestFooterFuncLpi(t *testing.T) {
+	pdf := gofpdf.New("P", "mm", "A4", "")
+	var (
+		oldFooterFnc  = "oldFooterFnc"
+		bothPages     = "bothPages"
+		firstPageOnly = "firstPageOnly"
+		lastPageOnly  = "lastPageOnly"
+	)
 
+	// This set just for testing, only set SetFooterFuncLpi.
+	pdf.SetFooterFunc(func() {
+		pdf.SetY(-15)
+		pdf.SetFont("Arial", "I", 8)
+		pdf.CellFormat(0, 10, oldFooterFnc,
+			"", 0, "C", false, 0, "")
+	})
+	pdf.SetFooterFuncLpi(func(lastPage bool) {
+		pdf.SetY(-15)
+		pdf.SetFont("Arial", "I", 8)
+		pdf.CellFormat(0, 10, bothPages, "", 0, "L", false, 0, "")
+		if !lastPage {
+			pdf.CellFormat(0, 10, firstPageOnly, "", 0, "C", false, 0, "")
+		} else {
+			pdf.CellFormat(0, 10, lastPageOnly, "", 0, "C", false, 0, "")
+		}
+	})
+	pdf.AddPage()
+	pdf.SetFont("Arial", "B", 16)
+	for j := 1; j <= 40; j++ {
+		pdf.CellFormat(0, 10, fmt.Sprintf("Printing line number %d", j),
+			"", 1, "", false, 0, "")
+	}
+	if pdf.Error() != nil {
+		t.Fatalf("not expecting error when rendering text")
+	}
+	w := &bytes.Buffer{}
+	if err := pdf.Output(w); err != nil {
+		t.Errorf("got err:%v want nil")
+	}
+	b := w.Bytes()
+	if bytes.Contains(b, []byte(oldFooterFnc)) {
+		t.Errorf("Not expecting %s render on pdf when FooterFncLpi is set", oldFooterFnc)
+	}
+	got := bytes.Count(b, []byte("bothPages"))
+	if got != 2 {
+		t.Errorf("footer %s should render on two page got:%d", bothPages, got)
+	}
+	got = bytes.Count(b, []byte(firstPageOnly))
+	if got != 1 {
+		t.Errorf("footer %s should render only on first page got:%d", firstPageOnly, got)
+	}
+	got = bytes.Count(b, []byte(lastPageOnly))
+	if got != 1 {
+		t.Errorf("footer %s should render only on first page got:%d", lastPageOnly, got)
+	}
+	f := bytes.Index(b, []byte(firstPageOnly))
+	l := bytes.Index(b, []byte(lastPageOnly))
+	if f > l {
+		t.Errorf("index %s : %d should less than indec of %s : %d", f, l)
+	}
 }
 
 type fontResourceType struct {