1 files changed, 120 insertions, 0 deletions
diff --git a/acf/model/field.lua b/acf/model/field.lua
new file mode 100644
index 0000000..cfa14b9
--- /dev/null
+++ b/acf/model/field.lua
@@ -0,0 +1,120 @@
+--[[
+Copyright (c) 2012 Kaarle Ritvanen
+See LICENSE file for license details
+--]]
+
+module(..., package.seeall)
+
+local node = require('acf.model.node')
+
+local object = require('acf.object')
+local class = object.class
+local super = object.super
+
+local map = require('acf.util').map
+
+
+local function contains(list, value)
+   for k, v in ipairs(list) do if v == value then return true end end
+   return false
+end
+
+local function auto_ui_name(name)
+   if not name then return end
+   return string.gsub(string.upper(string.sub(name, 1, 1))..string.sub(name, 2),
+		      '_', ' ')
+end
+
+
+Field = class()
+
+function Field:init(params)
+   for k, v in pairs(params or {}) do if not self[k] then self[k] = v end end
+
+   if self.choice and not self['ui-choice'] then
+      self['ui-choice'] = map(auto_ui_name, self.choice)
+   end
+
+   if not self.widget then
+      self.widget = self.choice and 'combobox' or 'field'
+   end
+end
+
+function Field:meta(txn, path, addr)
+   assert(self.dtype)
+   return {
+      name=self.name,
+      type=self.dtype,
+      required=self.required,
+      choice=self.choice,
+      description=self.description,
+      ['ui-name']=self['ui-name'] or auto_ui_name(self.name),
+      widget=self.widget,
+      ['ui-choice']=self['ui-choice']
+   }
+end
+
+function Field:load(txn, path, addr)
+   local value = txn:get(addr)
+   if value == nil then return self.default end
+   return value
+end
+
+function Field:_validate(txn, path, value)
+   if self.required and value == nil then
+      error('Required value not set: '..path)
+   end
+   if self.choice and value ~= nil and not contains(self.choice, value) then
+      error('Invalid value for '..path..': '..value)
+   end
+   if value ~= nil then self:validate(txn, path, value) end
+   return value
+end
+
+function Field:validate(txn, path, value) end
+
+function Field:save(txn, path, addr, value)
+   -- 2nd argument currenly not much used by backends
+   txn:set(addr, self.dtype, self:_validate(txn, path, value))
+end
+
+function Field:validate_saved(txn, path, addr)
+   self:save(txn, path, addr, self:load(txn, path, addr))
+end
+
+
+TreeNode = class(Field)
+
+function TreeNode:save(txn, path, addr, value)
+   -- TODO hack, allow preserving old instance on parent update
+   if value == path then return end
+
+   if object.isinstance(value, node.TreeNode) then
+      -- TODO clone if TreeNode has wrong path
+      assert(node.path(value) == path)
+      return
+   end
+
+   txn:set(addr)
+   if value then
+      assert(type(value) == 'table')
+      txn:set(addr, 'table')
+      local new = self:load(txn, path, addr, true)
+      for k, v in pairs(value) do new[k] = v end
+   end
+end
+
+
+Model = class(TreeNode)
+
+function Model:init(params)
+   super(self, Model):init(params)
+   assert(self.model)
+   self.dtype = 'model'
+   self.widget = self.dtype
+end
+
+function Model:load(txn, path, addr, create)
+   if not create and not txn:get(addr) then return end
+   return self.model(txn, path, addr)
+end