1 files changed, 122 insertions, 0 deletions
diff --git a/lua/clever_f/motion_plan.lua b/lua/clever_f/motion_plan.lua
new file mode 100644
index 0000000..362b978
--- /dev/null
+++ b/lua/clever_f/motion_plan.lua
@@ -0,0 +1,122 @@
+local domain = require("clever_f.domain")
+
+local M = {}
+local MotionPlanFactory = {}
+M.MotionPlanFactory = MotionPlanFactory
+
+local factory_records = setmetatable({}, { __mode = "k" })
+
+local function fail(message, level)
+  error(message, (level or 1) + 1)
+end
+
+local function normalize_options(options)
+  if options == nil then
+    return {}
+  end
+  if type(options) == "table" and type(options.sample_search) == "function" then
+    return { policy = options }
+  end
+  if type(options) ~= "table" then
+    fail("MotionPlanFactory options must be a table", 3)
+  end
+  return options
+end
+
+local function require_policy(service)
+  if service ~= nil and (type(service) ~= "table"
+      or type(service.sample_search) ~= "function")
+  then
+    fail("MotionPlanFactory policy must provide sample_search", 3)
+  end
+  return service
+end
+
+local factory_metatable = {
+  __index = MotionPlanFactory,
+  __newindex = function()
+    fail("MotionPlanFactory values are immutable", 2)
+  end,
+  __tostring = function()
+    return "motion-plan-factory"
+  end,
+  __metatable = "clever_f.motion_plan.MotionPlanFactory",
+}
+
+function MotionPlanFactory.new(options)
+  if MotionPlanFactory.is(options) then
+    return options
+  end
+  options = normalize_options(options)
+  local factory = setmetatable({}, factory_metatable)
+  factory_records[factory] = {
+    policy = require_policy(options.policy or options.policy_service),
+  }
+  return factory
+end
+
+function MotionPlanFactory.is(value)
+  return type(value) == "table" and factory_records[value] ~= nil
+end
+
+local function resolved_scope(factory, search_scope)
+  if search_scope == nil then
+    local policy = factory_records[factory].policy
+    if policy ~= nil then
+      search_scope = policy:sample_search().search_scope
+    else
+      search_scope = domain.SearchScope.BUFFER
+    end
+  elseif search_scope == "line" then
+    search_scope = domain.SearchScope.CURRENT_LINE
+  end
+  return domain.SearchScope.from_string(search_scope)
+end
+
+function MotionPlanFactory:build(
+  target_plan,
+  effective_descriptor,
+  search_scope,
+  endpoint_policy
+)
+  if not domain.TargetPlan.is(target_plan) then
+    fail("motion target plan must be a TargetPlan", 2)
+  end
+
+  return domain.ResolvedMotionPlan.new({
+    target_plan = target_plan,
+    descriptor = effective_descriptor,
+    search_scope = resolved_scope(self, search_scope),
+    endpoint_policy = endpoint_policy or domain.EndpointPolicy.REGULAR,
+  })
+end
+
+function M.new(options)
+  return MotionPlanFactory.new(options)
+end
+
+function M.build(
+  target_plan,
+  effective_descriptor,
+  search_scope,
+  endpoint_policy,
+  options
+)
+  return MotionPlanFactory.new(options):build(
+    target_plan,
+    effective_descriptor,
+    search_scope,
+    endpoint_policy
+  )
+end
+
+M.create = M.build
+M.resolve = M.build
+
+setmetatable(M, {
+  __call = function(_, options)
+    return MotionPlanFactory.new(options)
+  end,
+})
+
+return M