initial version

1 files changed, 129 insertions, 0 deletions

diff --git a/acf/model/node.lua b/acf/model/node.lua
new file mode 100644
index 0000000..39a0d92
--- /dev/null
+++ b/acf/model/node.lua
@@ -0,0 +1,129 @@
+--[[
+Copyright (c) 2012 Kaarle Ritvanen
+See LICENSE file for license details
+--]]
+
+module(..., package.seeall)
+
+local object = require('acf.object')
+local class = object.class
+local super = object.super
+
+local pth = require('acf.path')
+
+
+BoundField = class()
+
+function BoundField:init(parent, field)
+   local pmt = getmetatable(parent)
+   local mt = {}
+
+   function mt.__index(t, k)
+      local member = field[k]
+      if type(member) ~= 'function' then return member end
+      return function(self, ...)
+		local name
+		if field.name then name = field.name
+		else
+		   name = arg[1]
+		   table.remove(arg, 1)
+		end
+		return member(field,
+			      pmt.txn,
+			      pth.join(pmt.path, name),
+			      pmt.addr and pth.join(pmt.addr, name),
+			      unpack(arg))
+	     end
+   end
+
+   setmetatable(self, mt)
+end
+
+
+TreeNode = class()
+
+function TreeNode:init(txn, path, addr)
+   local mt = getmetatable(self)
+   mt.txn = txn
+   mt.path = path
+   mt.addr = addr
+end
+
+function TreeNode:search(path)
+   if #path == 0 then return self end
+   local next = path[1]
+   table.remove(path, 1)
+   return TreeNode.search(self[next], path)
+end
+
+
+Collection = class(TreeNode)
+
+function Collection:init(txn, path, addr, field, required)
+   super(self, Collection):init(txn, path, addr)
+
+   if required then
+      txn.validate[path] = function()
+			      if #txn:get(addr) == 0 then
+				 error('Collection cannot be empty: '..path)
+			      end
+			   end
+   end
+
+   self.init = nil
+   self.search = nil
+
+   local mt = getmetatable(self)
+
+   mt.field = BoundField(self, field)
+   mt.meta = {type='collection', members=mt.field:meta()}
+   function mt.mmeta(name) return mt.meta.members end
+   function mt.members() return txn:get(addr) or {} end
+   
+   function mt.__index(t, k) return mt.field:load(k) end
+   function mt.__newindex(t, k, v) mt.field:save(k, v) end
+end
+
+
+PrimitiveList = class(Collection)
+
+function PrimitiveList:init(txn, path, addr, field, required)
+   super(self, PrimitiveList):init(txn, path, addr, field, required)
+
+   local mt = getmetatable(self)
+   local index = mt.__index
+
+   function mt.__index(t, k)
+      if type(k) == 'number' then return index(t, k) end
+
+      for i, j in ipairs(txn:get(addr) or {}) do
+	 assert(i == tonumber(j))
+	 if mt.field:load(i) == k then return k end
+      end
+      error('Value does not exist: '..k)
+   end
+end
+
+
+-- experimental
+Mixed = class(Collection)
+
+function Mixed:init(txn, path, addr, field, required)
+   super(self, Mixed):init(txn, path, addr, field, required)
+   -- TODO dynamic meta: list non-leaf children
+   getmetatable(self).meta = {type='mixed'}
+end
+
+
+local function meta_func(attr)
+   return function(node, ...)
+	     local res = getmetatable(node)[attr]
+	     if type(res) == 'function' then return res(unpack(arg)) end
+	     return res
+	  end
+end
+
+members = meta_func('members')
+meta = meta_func('meta')
+mmeta = meta_func('mmeta')
+path = meta_func('path')