Implement component library

src/lua/core/component.lua

@@ -1,9 +1,124 @@
 local component = {}
 local api = {}
+local components = {}
+
 component.api = api
+component.components = components
+
+local componentCallback = {
+  __call = function(self, ...) return components[self.address].rawproxy[self.name](...) end,
+  __tostring = function(self) return (components[self.address] ~= nil and components[self.address].doc[self.name] ~= nil) and components[self.address].doc[self.name] or "function" end
+}
 
 function component.prepare()
-	print("Assembling initial component tree")
+  print("Assembling initial component tree")
+end
+
+function api.register(address, ctype, proxy, doc)
+  checkArg(2, ctype, "string")
+  checkArg(3, proxy, "table")
+  if type(address) ~= "string" then
+    address = random.uuid()
+  end
+  if components[address] ~= nil then
+    return nil, "component already at address"
+  end
+  components[address] = {address = address, type = ctype, doc = doc or {}}
+  components[address].rawproxy = proxy
+  components[address].proxy = {}
+  for k,v in pairs(proxy) do
+    if type(v) == "function" then
+      components[address].proxy = setmetatable({name=k,address=address}, componentCallback)
+    else
+      components[address].proxy = v
+    end
+  end
+  computer.pushSignal("component_added", address, ctype)
+  return true
+end
+
+function api.unregister(address)
+  checkArg(1, address, "string")
+  if components[address] == nil then
+    return nil, "no component at address"
+  end
+  local ctype = components[address].type
+  components[address] = nil
+  computer.pushSignal("component_removed", address, ctype)
+  return true
+end
+
+function api.doc(address, method)
+  checkArg(1, address, "string")
+  checkArg(2, method, "string")
+  if not components[address] then
+    error("No such component")
+  end
+  return components[address].doc[method]
+end
+
+function api.invoke(address, method, ...)
+  checkArg(1, address, "string")
+  checkArg(2, method, "string")
+  if not components[address] then
+    error("No such component")
+  end
+  if not components[address].rawproxy[method] then
+    error("No such method")
+  end
+  return components[address].rawproxy[method](...)
+end
+
+function api.list(filter, exact)
+  checkArg(1, filter, "string", "nil")
+  local list = {}
+  for addr, c in pairs(components) do
+    if not filter or ((exact and c.type or c.type:sub(1, #filter)) == filter) then
+      list[addr] = c.type
+    end
+  end
+  local key = nil
+  return setmetatable(list, {__call=function()
+        key = next(list, key)
+        if key then
+            return key, list[key]
+        end
+    end})
+end
+
+function api.methods(address)
+  checkArg(1, address, "string")
+  if not components[address] then
+    return nil, "No such component"
+  end
+  local list = {}
+  for k, v in pairs(components[address].rawproxy) do
+    if type(v) == "function" then
+      list[k] = true
+    end
+  end
+  return list
+end
+
+function api.fields(address)
+  checkArg(1, address, "string")
+  if not components[address] then
+    return nil, "No such component"
+  end
+  local list = {}
+  for k, v in pairs(components[address].rawproxy) do
+    if type(v) ~= "function" then
+      list[k] = true
+    end
+  end
+  return list
+end
+
+function api.proxy(address)
+  if not components[address] then
+    return nil, "No such component"
+  end
+  return components[address].proxy
 end
 
 return component

src/lua/core/computer.lua

@@ -1 +1,7 @@
+local computer = {}
 
+function computer.prepare( ... )
+	
+end
+
+return computer

src/lua/core/init.lua

@@ -1,3 +1,21 @@
+local function checkArg(n, have, ...)
+  have = type(have)
+  local function check(want, ...)
+    if not want then
+      return false
+    else
+      return have == want or check(...)
+    end
+  end
+  if not check(...) then
+    local msg = string.format("bad argument #%d (%s expected, got %s)",
+                              n, table.concat({...}, " or "), have)
+    error(msg, 3)
+  end
+end
+
+-------------------------------------------------------------------------------
+
 print("LuPI L1 INIT")
 modules = {}
 
@@ -8,7 +26,12 @@ local function loadModule(name)
   if not moduleCode[name] then
     error("No code for module " .. tostring(name))
   end
-  modules[name] = load(moduleCode[name])()
+  local code, reason = load(moduleCode[name])
+  if not code then
+    print("Failed loading module " .. name .. ": " .. reason)
+  else
+    modules[name] = code()
+  end
 end
 
 --Load modules
@@ -20,5 +43,6 @@ loadModule("boot")
 
 --Setup core modules
 modules.component.prepare()
+modules.computer.prepare()
 
 modules.boot.boot()