add csi_r (scrolling region)

[watch-my-terminal.git] / terminal.coffee

diff --git a/terminal.coffee b/terminal.coffee
index d371476..721ed80 100644 (file)
--- a/terminal.coffee
+++ b/terminal.coffee
@@ -20,10 +20,13 @@ class Terminal
                @partial = ''
                @saved_normal_screen = null
                @cursor_visible = true
+               @scroll_top = 0
+               @scroll_bottom = height - 1
                @resize width, height
 
        resize: (width, height) ->
                # FIXME: write a version that retains some of the data
+               # FIXME: clamp variables (eg x, y, saved.*, scrolling region) if getting smaller
                @width = width
                @height = height
                @text = []
@@ -54,20 +57,30 @@ class Terminal
                return
 
        add_new_line: ->
-               # clear top line
+               # clear the line at the top of the scrolling region
                for i in [0...@width]
-                       @text[0][i] = ' '
-                       @attributes[0][i] = 0x07
-               # move (newly cleared) top line to the bottom
-               tmp = @text.shift()
-               @text.push(tmp)
-               tmp = @attributes.shift()
-               @attributes.push(tmp)
+                       @text[@scroll_top][i] = ' '
+                       @attributes[@scroll_top][i] = 0x07
+
+               # move (newly cleared) top line to the bottom of the scrolling region
+               @text = [
+                       @text[0...@scroll_top]..., # up to but not including scroll top
+                       @text[@scroll_top + 1 .. @scroll_bottom]..., # scroll region except top line of it
+                       @text[@scroll_top], # top line of scroll region (already cleared)
+                       @text[@scroll_bottom + 1 ... @height]... # rest of screen
+               ]
+               @attributes = [
+                       @attributes[0...@scroll_top]..., # up to but not including scroll top
+                       @attributes[@scroll_top + 1 .. @scroll_bottom]..., # scroll region except top line of it
+                       @attributes[@scroll_top], # top line of scroll region (already cleared)
+                       @attributes[@scroll_bottom + 1 ... @height]... # rest of screen
+               ]
+
                # slide cursor up with rest of text
                @y -= 1
 
        wrap_to_next_line: ->
-               if @y is @height - 1
+               if @y is @scroll_bottom
                        @add_new_line()
                @y += 1
                @x = 0
@@ -121,6 +134,7 @@ class Terminal
                @y -= lines
                if @y < 0
                        @y = 0
+               return
 
        # move cursor down
        csi_B: (lines) ->
@@ -128,6 +142,7 @@ class Terminal
                @y += lines
                if @y >= @height
                        @y = @height - 1
+               return
 
        # move cursor right
        csi_C: (cols) ->
@@ -135,6 +150,7 @@ class Terminal
                @x += cols
                if @x >= @width
                        @x = @width - 1
+               return
 
        # move cursor left
        csi_D: (cols) ->
@@ -142,6 +158,7 @@ class Terminal
                @x -= cols
                if @x < 0
                        @x = 0
+               return
 
        # set cursor position (one based)
        csi_H: (row, column) ->
@@ -162,6 +179,7 @@ class Terminal
                #move the cursor
                @x = column
                @y = row
+               return
 
        # clear to screen edge(es)
        csi_J: (direction) ->
@@ -238,6 +256,8 @@ class Terminal
                                                        @attributes[y].push 0x07
                                else
                                        console.log "confusing arg for csiq_h: #{arg}"
+               return
+
        # unmisc
        csiq_l: ->
                args = []
@@ -257,6 +277,7 @@ class Terminal
                                        @saved_normal_screen = null
                                else
                                        console.log "confusing arg for csiq_l: #{arg}"
+               return
 
        # set color, bold, underline, etc
        csi_m: ->
@@ -398,6 +419,18 @@ class Terminal
                                        @a = 0
                return
 
+       # set scrolling region
+       csi_r: (top, bottom) ->
+               top = -1 + parseInt @fix_esc_arg top, '1'
+               bottom = -1 + parseInt @fix_esc_arg bottom, '10000'
+               if top < 0
+                       top = 0
+               if bottom >= @height
+                       bottom = @height - 1
+               @scroll_top = top
+               @scroll_bottom = bottom
+               return
+
        # str is the whole escape sequence (minus the esc[ prefix)
        update_sequence: (str) ->
                prefix = 'csi_'