Add page up/down

README.md

@@ -120,6 +120,8 @@ jid < file.json
 |`CTRL` + `K`|Scroll json buffer 1 line upwards|
 |`CTRL` + `G`|Scroll json buffer to bottom|
 |`CTRL` + `T`|Scroll json buffer to top|
+|`CTRL` + `N`|Scroll json buffer 'Page Down'|
+|`CTRL` + `P`|Scroll json buffer 'Page Up'|
 |`CTRL` + `L`|Change view mode whole json or keys (only object)|
 |`ESC`|Hide a candidate box|
 

cmd/jid/jid.go

@@ -8,7 +8,7 @@ import (
 	"github.com/simeji/jid"
 )
 
-const VERSION = "0.7.3"
+const VERSION = "0.7.5"
 
 func main() {
 	content := os.Stdin
@@ -114,6 +114,12 @@ CTRL-G
 CTRL-T
   Scroll json buffer to top
 
+CTRL-N
+  Scroll json buffer 'Page Down'
+
+CTRL-P
+  Scroll json buffer 'Page Up'
+
 CTRL-L
   Change view mode whole json or keys (only object)
 

engine.go

@@ -4,7 +4,7 @@ import (
 	"io"
 	"strings"
 
-	"github.com/nsf/termbox-go"
+	termbox "github.com/nsf/termbox-go"
 )
 
 const (
@@ -151,6 +151,12 @@ func (e *Engine) Run() EngineResultInterface {
 				e.scrollToBottom(len(contents))
 			case termbox.KeyCtrlT:
 				e.scrollToTop()
+			case termbox.KeyCtrlN:
+				_, h := termbox.Size()
+				e.scrollPageDown(len(contents), h)
+			case termbox.KeyCtrlP:
+				_, h := termbox.Size()
+				e.scrollPageUp(h)
 			case termbox.KeyCtrlL:
 				e.toggleKeymode()
 			case termbox.KeyCtrlU:
@@ -165,14 +171,14 @@ func (e *Engine) Run() EngineResultInterface {
 					var err error
 					if e.prettyResult {
 						cc, _, _, err = e.manager.GetPretty(e.query, true)
-					}else{
+					} else {
 						cc, _, _, err = e.manager.Get(e.query, true)
 					}
 
 					return &EngineResult{
-						content:       cc,
-						qs:            e.query.StringGet(),
-						err:           err,
+						content: cc,
+						qs:      e.query.StringGet(),
+						err:     err,
 					}
 				}
 				e.confirmCandidate()
@@ -253,6 +259,22 @@ func (e *Engine) scrollToTop() {
 	e.contentOffset = 0
 }
 
+func (e *Engine) scrollPageDown(rownum int, height int) {
+	co := rownum - 1
+	if o := rownum - e.contentOffset; o > height {
+		co = e.contentOffset + (height - DefaultY)
+	}
+	e.contentOffset = co
+}
+
+func (e *Engine) scrollPageUp(height int) {
+	co := 0
+	if o := e.contentOffset - (height - DefaultY); o > 0 {
+		co = o
+	}
+	e.contentOffset = co
+}
+
 func (e *Engine) toggleKeymode() {
 	e.keymode = !e.keymode
 }

engine_test.go

@@ -114,6 +114,43 @@ func TestScrollToBottomAndTop(t *testing.T) {
 	assert.Equal(0, e.contentOffset)
 }
 
+func TestScrollPageUpDown(t *testing.T) {
+	var assert = assert.New(t)
+	e := getEngine(`{"named":"go","NameTest":[1,2,3]}`, "")
+
+	cl := len(e.getContents())
+	// Then DefaultY = 1
+	e.scrollPageDown(cl, 3)
+	assert.Equal(2, e.contentOffset)
+	e.scrollPageDown(cl, 3)
+	assert.Equal(4, e.contentOffset)
+
+	e.scrollPageUp(3)
+	assert.Equal(2, e.contentOffset)
+
+	// term height changed
+	e.scrollPageDown(cl, 5)
+	assert.Equal(6, e.contentOffset)
+
+	e.scrollPageDown(cl, 5)
+	assert.Equal(7, e.contentOffset)
+
+	e.scrollPageDown(cl, 5)
+	assert.Equal(7, e.contentOffset)
+
+	e.scrollPageUp(5)
+	assert.Equal(3, e.contentOffset)
+
+	e.scrollPageUp(5)
+	assert.Equal(0, e.contentOffset)
+
+	e.scrollPageUp(5)
+	assert.Equal(0, e.contentOffset)
+
+	// term height > content size + default Y (a filter query line)
+	e.scrollPageDown(cl, 10)
+	assert.Equal(7, e.contentOffset)
+}
 func TestGetContents(t *testing.T) {
 	var assert = assert.New(t)