Add custom function option for UUID generation (#194)

* add custom function option for UUID generation

* add docs for new UUID custom function option

README.md

@@ -302,7 +302,12 @@ require('telekasten').setup({
     -- "uuid-title" - Prefix title by uuid
     -- "title-uuid" - Suffix title with uuid
     new_note_filename = "title",
-    -- file uuid type ("rand" or input for os.date()")
+
+    --[[ file UUID type
+        - "rand"
+        - string input for os.date()
+        - or custom lua function that returns a string
+    --]]
     uuid_type = "%Y%m%d%H%M",
     -- UUID separator
     uuid_sep = "-",

doc/telekasten.txt

@@ -243,8 +243,9 @@ telekasten.setup({opts})
 
                                            *telekasten.settings.uuid_type*
     uuid_type: ~
-        Type of UUID. Could be 'rand' for a random 6 character string, or a
-        time format to input in os.date() such as %Y%m%d%H%M.
+        Type of UUID. Could be 'rand' for a random 6 character string, a
+        time format to input in os.date() such as '%Y%m%d%H%M', or any lua
+        function like os.time() that returns a string.
 
         Default: '%Y%m%d%H%M'
 

lua/telekasten.lua

@@ -64,7 +64,12 @@ local function defaultConfig(home)
         -- "uuid-title" - Prefix title by uuid
         -- "title-uuid" - Suffix title with uuid
         new_note_filename = "title",
-        -- file uuid type ("rand" or input for os.date()")
+
+        --[[ file UUID type
+           - "rand"
+           - string input for os.date()
+           - or custom lua function that returns a string
+        --]]
         uuid_type = "%Y%m%d%H%M",
         -- UUID separator
         uuid_sep = "-",
@@ -208,10 +213,12 @@ local function get_uuid(opts)
     opts.uuid_type = opts.uuid_type or M.Cfg.uuid_type
 
     local uuid
-    if opts.uuid_type ~= "rand" then
-        uuid = os.date(opts.uuid_type)
-    else
+    if opts.uuid_type == "rand" then
         uuid = random_variable(6)
+    elseif type(opts.uuid_type) == "function" then
+        uuid = opts.uuid_type()
+    else
+        uuid = os.date(opts.uuid_type)
     end
     return uuid
 end