new ipelet for pagenumbers

diff --git a/ipelets/pagenumbers/pagenumbers.lua b/ipelets/pagenumbers/pagenumbers.lua
new file mode 100644 (file)
index 0000000..9e556d3
--- /dev/null
+++ b/ipelets/pagenumbers/pagenumbers.lua
@@ -0,0 +1,158 @@
+----------------------------------------------------------------------
+-- pagenumbers ipelet
+----------------------------------------------------------------------
+label = "Pagenumbers"
+
+about = [[ blubb ]]
+
+local prefix = "pagenumbers"
+local format_layer = prefix .. "_format"
+local pagenr_layer = prefix .. "_page"
+local dont_count_layer = prefix .. "_dont_count"
+
+local page_wildcard = "%[page%]" -- ignore the %
+
+----------------------------------------------------------------------
+-- adding page numbers before every run of latex ---------------------
+
+-- saving the old function
+function _G.MODEL:pagenumbers_backup_runLatex() end
+_G.MODEL.pagenumbers_backup_runLatex = _G.MODEL.runLatex
+
+function _G.MODEL:runLatex()
+   refresh_pagenumbers(self)
+   self:pagenumbers_backup_runLatex()
+end
+
+
+----------------------------------------------------------------------
+-- refresh the page numbers ------------------------------------------
+
+function refresh_pagenumbers(model)
+   -- first find the pagenumber objects that should be printed on
+   -- every page
+   local pagenr_objects = find_pagenr_objects(model)
+
+   -- if something was found, print the page numbers on every page
+   if #pagenr_objects > 0 then
+      -- using the undo-redo construct although there is nothing to
+      -- undo (otherwise, the view does not refresh correctly)
+      local t = { label = "refresh pagenumbers (not undoable)",
+                 model = model }
+      t.redo = function (t, doc)
+        print_on_ever_page(t.model, pagenr_objects)
+      end
+      t.undo = function (t, doc)
+        -- no undo possible..
+      end
+      model:register(t)
+   end
+end
+
+----------------------------------------------------------------------
+-- find pagenumber objects -------------------------------------------
+
+function find_pagenr_objects(model)
+   res = {}
+   p1 = model.doc[1]
+   for i, obj, sel, layer in p1:objects() do
+      -- find layer called format_layer
+      if layer == format_layer then
+        if obj:type() == "text" then
+           res[#res+1] = obj
+        end
+      end
+   end
+   
+   return res
+end
+
+----------------------------------------------------------------------
+-- print given pagenumber objects on every page ----------------------
+
+function print_on_ever_page(model, pagenr_objects)
+   local doc = model.doc
+   print "copy.."
+   -- first create the clones
+   -- print "create clones"
+   local clones = {}
+   for i = 1, #doc do
+      local clone_objs = {}
+      for j, obj in ipairs(pagenr_objects) do
+        clone_objs[j] = obj:clone()
+        -- print (i, j, clone_objs[j])
+      end
+      clones[i] = clone_objs
+   end
+   
+   -- then add the clones
+   local pagenr = 0
+   for i = 1, #doc do
+      -- print("get page", i)
+      local p = doc[i]
+      
+      -- increase the pagenr, if the current page does not contain the
+      -- dont_count layer
+      if not page_has_layer(p, dont_count_layer) then
+        pagenr = pagenr + 1
+      end
+
+      -- if the layer does not exists, create it
+      -- print "create layer"
+      if not page_has_layer(p, pagenr_layer) then
+        p:addLayer(pagenr_layer)
+        make_layer_visible(p, pagenr_layer)
+      end
+      
+      -- lock the layer
+      p:setLocked(pagenr_layer, true)
+
+      -- remove all objects from the layer
+      clear_layer(p, pagenr_layer)
+
+      -- add the pagenumbers to the layer
+      -- print "add pagenumbers"
+      for j = 1, #pagenr_objects do
+        -- print (i, j, clones[i][j])
+        -- print(string.gsub(clones[i][j]:text(), page_wildcard, pagenr))
+        local repl_text = clones[i][j]:text():gsub(page_wildcard, pagenr)
+        clones[i][j]:setText(repl_text)
+        p:insert(nil, clones[i][j], nil, pagenr_layer)
+      end
+   end
+end
+
+----------------------------------------------------------------------
+-- some helper function ----------------------------------------------
+
+-- make a layer visible on all vies of a page
+function make_layer_visible(p, layer)
+   for i = 1, p:countViews() do
+      p:setVisible(i, layer, true)
+   end
+end
+
+-- remove all objects in a given layer
+function clear_layer(p, layer)
+   local i = 1
+   while i <= #p do
+      if p:layerOf(i) == layer then
+        p:remove(i)
+      else
+        i = i + 1
+      end
+   end
+end
+
+-- returns true if and only if the page p contains the given layer
+function page_has_layer(p, layer)
+   for _, layer_ in ipairs(p:layers()) do
+      if layer == layer_ then
+        return true
+      end
+   end
+   return false
+end
+
+
+----------------------------------------------------------------------