oda in lua?

scripts/0-rds2_oda.lua

@@ -0,0 +1,57 @@
+local RDS2_ODA = { aid = 0, data = 0, handler = false }
+
+function RDS2_ODA.new(aid, data, handler)
+    local instance = { aid = aid or 0, data = data or 0, handler = handler or false }
+    setmetatable(instance, { __index = RDS2_ODA })
+    return instance
+end
+
+local RDS2_ODAs = {}
+local RDS2_ODA_aid = true
+local RDS2_ODA_pointer = 1
+
+---This function is defined externally
+---@param aid integer
+---@param data integer
+---@return integer oda_id
+function register_oda_rds2(aid, data)
+    local oda = RDS2_ODA.new(aid, data, false)
+    table.insert(RDS2_ODAs, oda)
+    return #RDS2_ODAs
+end
+
+---This function is defined externally
+---@param oda_id integer
+---@param data integer
+function set_oda_id_data_rds2(oda_id, data)
+    if oda_id > #RDS2_ODAs then return end
+    RDS2_ODAs[oda_id].data = data
+end
+
+---This function is defined externally
+---@param oda_id integer
+---@param func RDS2_ODAHandler
+function set_oda_handler_rds2(oda_id, func)
+    if oda_id > #RDS2_ODAs then return end
+    RDS2_ODAs[oda_id].handler = func
+end
+
+function rds2_group(stream)
+    if #RDS2_ODAs == 0 then return false, 0, 0, 0, 0 end
+    if RDS2_ODA_pointer > #RDS2_ODAs then RDS2_ODA_pointer = 1 end
+    local oda = RDS2_ODAs[RDS2_ODA_pointer]
+    local channel = (RDS2_ODA_pointer & 0x40) << 8
+    RDS2_ODA_pointer = RDS2_ODA_pointer + 1
+    if RDS2_ODA_aid then
+        -- TODO: add support for the multi aid thing (page 49)
+        RDS2_ODA_aid = not RDS2_ODA_aid
+        return true, 1 << 15 | channel, oda.aid, (oda.data & 0xffff0000) >> 16, (oda.data & 0xffff)
+    else
+        RDS2_ODA_aid = not RDS2_ODA_aid
+        if oda.handler then
+            local generated, a, b, c, d = oda.handler(stream)
+            return generated, 1 << 14 | channel | a, b, c, d
+        end
+        return true, 1 << 15 | channel, oda.aid, (oda.data & 0xffff0000) >> 16, (oda.data & 0xffff)
+    end
+end