restructuring

util/persistence.lua

@@ -0,0 +1,144 @@
+local private, public = {}, {}
+Aux.persistence = public
+
+aux_datasets = {}
+
+function public.on_load()
+    Aux.control.as_soon_as(function() private.faction = UnitFactionGroup('player') return private.faction end, Aux.util.pass)
+    private.realm = GetCVar('realmName')
+end
+
+function private.get_dataset_key()
+	return private.realm..'|'..private.faction
+end
+
+function public.load_dataset()
+    local dataset_key = private.get_dataset_key()
+    aux_datasets[dataset_key] = aux_datasets[dataset_key] or {}
+    return aux_datasets[dataset_key]
+end
+
+function public.read(schema, str)
+    if schema == 'string' then
+        return str
+    elseif schema == 'boolean' then
+        return str == '1'
+    elseif schema == 'number' then
+        return tonumber(str)
+    elseif type(schema) == 'table' and schema[1] == 'list' then
+        return public.read_list(schema, str)
+    elseif type(schema) == 'table' and schema[1] == 'record' then
+        return public.read_record(schema, str)
+    else
+        error('Unknown schema.')
+    end
+end
+
+function public.write(schema, obj)
+    if schema == 'string' then
+        return obj or ''
+    elseif schema == 'boolean' then
+        return obj and '1' or '0'
+    elseif schema == 'number' then
+        return obj and tostring(obj) or ''
+    elseif type(schema) == 'table' and schema[1] == 'list' then
+        return public.write_list(schema, obj)
+    elseif type(schema) == 'table' and schema[1] == 'record' then
+        return public.write_record(schema, obj)
+    else
+        error('Unknown schema.')
+    end
+end
+
+function public.read_list(schema, str)
+    if str == '' then
+        return {}
+    end
+
+    local separator = schema[2]
+    local element_type = schema[3]
+    local parts = Aux.util.split(str, separator)
+    return Aux.util.map(parts, function(part)
+        return public.read(element_type, part)
+    end)
+end
+
+function public.write_list(schema, list)
+    local separator = schema[2]
+    local element_type = schema[3]
+    local parts = Aux.util.map(list, function(element)
+        return public.write(element_type, element)
+    end)
+    return Aux.util.join(parts, separator)
+end
+
+function public.read_record(schema, str)
+    local separator = schema[2]
+    local record = {}
+    local parts = Aux.util.split(str, separator)
+    for i=3,getn(schema) do
+        local key, type = next(schema[i])
+        record[key] = public.read(type, parts[i - 2])
+    end
+    return record
+end
+
+function public.write_record(schema, record)
+    local separator = schema[2]
+    local parts = {}
+    for i=3,getn(schema) do
+        local key, type = next(schema[i])
+        tinsert(parts, public.write(type, record[key]))
+    end
+    return Aux.util.join(parts, separator)
+end
+
+function public.serialize(data, separator, compactor)
+
+    local data_string = ''
+    local i = 1
+    while i <= getn(data) do
+        local element, count = data[i], 1
+        while compactor and data[i + 1] == element do
+            count = count + 1
+            i = i + 1
+        end
+        local part = count > 1 and element..compactor..count or element
+        data_string = data_string..(i == 1 and '' or separator)..part
+        i = i + 1
+    end
+
+    return data_string
+end
+
+function public.deserialize(data_string, separator, compactor)
+    if not data_string or data_string == '' then
+        return {}
+    end
+
+    local data = {}
+    while true do
+        local start_index, _ = strfind(data_string, separator, 1, true)
+
+        local part
+        if start_index then
+            part = strsub(data_string, 1, start_index - 1)
+            data_string = strsub(data_string, start_index + 1)
+        else
+            part = strsub(data_string, 1)
+        end
+
+        if compactor and strfind(part, compactor, 1, true) then
+            local compactor_index, _ = strfind(part, compactor, 1, true)
+            for i=1, tonumber(strsub(part, compactor_index + 1)) do
+               tinsert(data, strsub(part, 1, compactor_index - 1))
+            end
+        else
+            tinsert(data, part)
+        end
+
+        if not start_index then
+            return data
+        end
+    end
+end