folds + very basic indentation

lua/perga/init.lua

@@ -1,11 +1,38 @@
 local M = {}
 
+local function get_indent(lnum)
+    local prev_line = vim.fn.getline(lnum - 1)
+    local curr_line = vim.fn.getline(lnum)
+    
+    local prev_indent = vim.fn.indent(lnum - 1)
+    local shiftwidth = vim.bo.shiftwidth
+    
+    if prev_line:match(';') then
+        return 0
+    end
+
+    if prev_line:match(':=') then
+        return prev_indent + shiftwidth
+    end
+    
+    return prev_indent
+end
+
 function M.setup(opts)
     vim.filetype.add({
         extension = { pg = 'perga' }
     })
 
-    vim.opt.commentstring = '-- %s'
+    vim.api.nvim_create_autocmd("FileType", {
+        pattern = "perga",
+        callback = function()
+            _G.get_perga_indent = get_indent
+            
+            vim.bo.indentexpr = 'v:lua.get_perga_indent(v:lnum)'
+            vim.bo.indentkeys = '0{,0},0),0],!^F,o,O,e,:,='
+            vim.opt_local.commentstring = '-- %s'
+        end
+    })
 
     local parser_config = require 'nvim-treesitter.parsers'.get_parser_configs()
     parser_config.perga = {

queries/perga/folds.scm

@@ -0,0 +1,6 @@
+[
+    (definition)
+    (block_comment)
+    (labs)
+    (pabs)
+] @fold

queries/perga/highlights.scm

@@ -6,6 +6,7 @@
 [(star) (square)] @constant.builtin
 
 (comment) @comment
+(block_comment) @comment
 
 [ "(" ")" ] @punctuation.bracket
 
@@ -17,3 +18,6 @@
 
 (param_block
   type: (expr) @type)
+
+(ascription
+  type: (expr) @type)