From 790fe120c484c9bc3736aacc1fdaa9904177e383 Mon Sep 17 00:00:00 2001
From: Jason Woofenden <jason@jasonwoof.com>
Date: Wed, 30 Jan 2013 23:14:59 -0500
Subject: [PATCH] csiq_ prefix, alt screen flipping, clamp csi_H

---
 terminal.coffee |   64 ++++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 54 insertions(+), 10 deletions(-)

diff --git a/terminal.coffee b/terminal.coffee
index f3ed817..abc006a 100644
--- a/terminal.coffee
+++ b/terminal.coffee
@@ -18,6 +18,7 @@ class Terminal
 		@y = 0
 		@a = 0x000007 # cursor attributes
 		@partial = ''
+		@saved_normal_screen = null
 		@resize width, height
 
 	resize: (width, height) ->
@@ -113,17 +114,23 @@ class Terminal
 	csi_H: (row, column) ->
 		row = 0 + @fix_esc_arg row, 1
 		column = 0 + @fix_esc_arg column, 1
+
 		# convert to 0 base
 		column -= 1
-		if 0 <= column < @width
-			@x = column
-		else
-			console.log "tried to move cursor to invalid column: #{column}"
-		row -= 1
-		if 0 <= row < @height
-			@y = row
-		else
-			console.log "tried to move cursor to invalid row: #{row}"
+
+		#clamp values
+		if column < 0
+			column = 0
+		else if column >= @width
+			column = @width - 1
+		if row < 0
+			row = 0
+		if row >= @height
+			row = @height - 1
+
+		#move the cursor
+		@x = column
+		@y = row
 
 	# clear lines (implemented inclusive of the current line)
 	csi_J: (direction) ->
@@ -163,6 +170,39 @@ class Terminal
 					@attributes[@y][i] = @a
 			else
 				console.log "confusing arg for csi_K: #{direction}"
+	
+	# misc
+	csiq_h: ->
+		args = []
+		for i in arguments
+			switch @fix_esc_arg i, ''
+				when '1049'
+					if @saved_normal_screen?
+						console.log "ignoring request to switch to the alt screen because we're already on the alt screen"
+						return
+					@saved_normal_screen = [@x, @y, @text, @attributes]
+					@text = []
+					@attributes = []
+					for y in [0...@height]
+						@text[y] = []
+						@attributes[y] = []
+						for x in [0...@width]
+							@text[y].push ' '
+							@attributes[y].push 0
+	# unmisc
+	csiq_l: ->
+		args = []
+		for i in arguments
+			switch @fix_esc_arg i, ''
+				when '1049'
+					if not @saved_normal_screen?
+						console.log "ignoring request to switch to the normal screen because we're already on the normal screen"
+						return
+					@x = @saved_normal_screen[0]
+					@y = @saved_normal_screen[1]
+					@text = @saved_normal_screen[2]
+					@attributes = @saved_normal_screen[3]
+					@saved_normal_screen = null
 
 	# set color, bold, underline, etc
 	csi_m: ->
@@ -298,7 +338,11 @@ class Terminal
 
 	# str is the whole escape sequence (minus the esc[ prefix)
 	update_sequence: (str) ->
-		command = @["csi_#{str.substr str.length - 1}"]
+		prefix = 'csi_'
+		if str[0] is '?'
+			prefix = 'csiq_'
+			str = str.substr 1
+		command = @[prefix + str.substr(str.length - 1)]
 		if not command?
 			console.log "Unrecognized sequence: ESC[#{str}"
 			return
-- 
1.7.10.4