From 9d3defc47769f04bebdbf3f8ff5a60047be5a360 Mon Sep 17 00:00:00 2001
From: Yves Rizoud <yrizoud@gmail.com>
Date: Mon, 8 Nov 2010 01:23:11 +0000
Subject: [PATCH] Forgotten library (issue 399)

git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@1647 416bcca6-2ee7-4201-b75f-2eb2f807beb1
---
 share/grafx2/scripts/libs/memory.lua | 132 +++++++++++++++++++++++++++
 1 file changed, 132 insertions(+)
 create mode 100644 share/grafx2/scripts/libs/memory.lua

diff --git a/share/grafx2/scripts/libs/memory.lua b/share/grafx2/scripts/libs/memory.lua
new file mode 100644
index 00000000..22d1ea24
--- /dev/null
+++ b/share/grafx2/scripts/libs/memory.lua
@@ -0,0 +1,132 @@
+-- Persistence library:
+--   Memorize data for current function
+--   memory.save(tab) and tab=memory.load()
+--
+--   The data will be stored in file called
+--     ZZZ<calling_function_name>.dat
+--   in the lua directory 
+-- 
+-- Example 1:
+--
+--  -- Load initial values or set defaults
+--  arg = memory.load({picX=320,picY=200,scale=0})
+--  -- Run an inputbox
+--  OK,arg.picX,arg.picY,arg.scale = inputbox("Image Size")",
+--    "Width",    arg.picX,  1,2048,0,
+--    "Height",   arg.picY,  1,2048,0,
+--    "Scale",    arg.scale, 0,1,0);
+--  if OK == true then
+--    -- Save the selected values
+--    memory.save(arg)
+--  end
+
+-- Example 2:
+--
+--  -- Load initial values or set defaults
+--  arg = memory.load({x=320,y=200,scale=0})
+--  picX=arg.x
+--  picY=arg.y
+--  scale=arg.scale
+--  -- Run an inputbox
+--  OK,picX,picY,scale = inputbox("Image Size")",
+--    "Width",    picX,  1,2048,0,
+--    "Height",   picY,  1,2048,0,
+--    "Scale",    scale, 0,1,0);
+--  if OK == true then
+--    -- Save the selected values
+--    memory.save({x=picX,y=picY,scale=scale})
+--  end
+
+  
+memory =
+{
+  serialize = function(o)
+    if type(o) == "number" then
+      return tostring(o)
+    elseif type(o) == "string" then
+      return string.format("%q", o)
+    --elseif type(o) == "table" then
+    --  io.write("{\n")
+    --  for k,v in pairs(o) do
+    --    io.write("  ", k, " = ")
+    --    memory.serialize(v)
+    --    io.write(",\n")
+    --  end
+    --  io.write("}\n")
+    else
+      error("cannot serialize a " .. type(o))
+    end
+  end;
+  
+  -- Return a string identifying the calling function.
+  -- Pass 1 for parent, 2 for grandparent etc.
+  callername = function(level)
+    local w
+    local last_slash
+    local info = debug.getinfo(level+1,"Sn")
+    local caller=tostring(info.name)
+    -- Function name if possible
+    if (caller~="nil") then
+      return caller
+    end
+    -- Otherwise, get file name, without extension
+   
+    -- Get part after directory name
+    last_slash=0
+    while true do
+      local pos = string.find(info.short_src, "/", last_slash+1)
+      if (pos==nil) then break end
+      last_slash=pos
+    end
+    caller=string.sub(info.short_src, last_slash+1)
+
+    -- Remove file extension
+    if (string.sub(caller,-4, -1)==".lua") then
+      caller=string.sub(caller, 1, -5)
+    end
+    return caller
+  end;
+  
+  -- Memorize some parameters.
+  save = function(o)
+    local caller=memory.callername(2)
+    --for k, v in pairs(o) do
+    --    messagebox(tostring(k))
+    --    messagebox(tostring(v))
+    --end
+    local f, e = io.open("ZZZ"..caller..".dat", "w");
+    if (f ~= nil) then
+      f:write("Entry {\n")
+      for k, v in pairs(o) do
+        if (type(v)=="number") then
+          f:write("  "..k.."="..memory["serialize"](v)..",\n")
+        end
+      end
+      f:write("}\n")
+      f:close()
+    end  
+  end;
+  
+  
+  -- Recover some saved parameters.
+  load = function(o)
+    local caller=memory.callername(2)
+    local i
+
+    function Entry (b)
+      -- Adds (or replaces) values in arg with those from b
+      for k, v in pairs(b) do
+        o[k]=v
+      end
+    end
+    local f = (loadfile("ZZZ"..caller..".dat"))
+    if (f ~= nil) then
+      f()
+    end
+
+    return o
+  end;
+
+}
+
+return memory