Return outcomes through ActionFacade

1 files changed, 67 insertions, 0 deletions

diff --git a/lua/clever_f/action_facade.lua b/lua/clever_f/action_facade.lua
new file mode 100644
index 0000000..5d8da67
--- /dev/null
+++ b/lua/clever_f/action_facade.lua
@@ -0,0 +1,67 @@
+local domain = require("clever_f.domain")
+local sequence_coordinator = require("clever_f.sequence_coordinator")
+
+local M = {}
+local ActionFacade = {}
+ActionFacade.__index = ActionFacade
+M.ActionFacade = ActionFacade
+
+local facade_records = setmetatable({}, { __mode = "k" })
+
+local function fail(message, level)
+  error(message, (level or 1) + 1)
+end
+
+function ActionFacade.new(options)
+  if ActionFacade.is(options) then
+    return options
+  end
+  local coordinator
+  if sequence_coordinator.SequenceCoordinator.is(options) then
+    coordinator = options
+  elseif type(options) == "table" then
+    coordinator = options.coordinator
+      or options.sequence_coordinator
+      or sequence_coordinator.new(options)
+  else
+    fail("ActionFacade options must be a table", 2)
+  end
+  if not sequence_coordinator.SequenceCoordinator.is(coordinator) then
+    fail("ActionFacade requires a SequenceCoordinator", 2)
+  end
+
+  local facade = setmetatable({}, ActionFacade)
+  facade_records[facade] = { coordinator = coordinator }
+  return facade
+end
+
+function ActionFacade.is(value)
+  return type(value) == "table" and facade_records[value] ~= nil
+end
+
+function ActionFacade:coordinator()
+  return facade_records[self].coordinator
+end
+
+function ActionFacade:primary(descriptor)
+  local outcome = self:coordinator():primary(descriptor)
+  if not domain.ActionOutcome.is(outcome) then
+    fail("SequenceCoordinator must return an ActionOutcome", 2)
+  end
+  return outcome
+end
+
+ActionFacade.invoke_primary = ActionFacade.primary
+ActionFacade.start = ActionFacade.primary
+
+function M.new(options)
+  return ActionFacade.new(options)
+end
+
+setmetatable(M, {
+  __call = function(_, options)
+    return ActionFacade.new(options)
+  end,
+})
+
+return M