feat: auto-uppercase keywords and auto-semicolon for END_* keywords

- Auto-uppercase SCL keywords (IF, CASE, FOR, NOT, AND, etc.) when typing space
- Auto-add semicolon after END_* keywords (END_IF, END_FOR, etc.) when:
  - Leaving insert mode on a line ending with END_*
  - Pressing Enter after typing END_*
- Added complete keyword list including TYPE, STRUCT, DATA_BLOCK, etc.
- Works for .scl, .udt, and .db files

lua/scl/auto_prefix.lua

@@ -33,9 +33,24 @@ local keywords = {
   "ORGANIZATION_BLOCK", "END_ORGANIZATION_BLOCK",
   "FUNCTION_BLOCK", "END_FUNCTION_BLOCK",
   "FUNCTION", "END_FUNCTION",
-  "RETURN",
+  "RETURN", "TYPE", "END_TYPE", "STRUCT", "END_STRUCT",
+  "DATA_BLOCK", "END_DATA_BLOCK",
+  "CONSTANT", "RETAIN", "NON_RETAIN",
 }
 
+-- Keywords that need semicolon after them (when at end of statement)
+local end_keywords = {
+  "END_IF", "END_FOR", "END_WHILE", "END_REPEAT", "END_CASE",
+  "END_VAR", "END_FUNCTION", "END_FUNCTION_BLOCK", "END_ORGANIZATION_BLOCK",
+  "END_TYPE", "END_STRUCT", "END_DATA_BLOCK", "END_REGION",
+}
+
+-- Map lowercase to uppercase for auto-conversion
+local keyword_map = {}
+for _, kw in ipairs(keywords) do
+  keyword_map[kw:lower()] = kw
+end
+
 -- Check if word is a keyword
 local function is_keyword(word)
   for _, kw in ipairs(keywords) do
@@ -393,6 +408,74 @@ local function on_dot_typed()
   end
 end
 
+-- Auto-uppercase keywords when typing space
+local function auto_uppercase_keyword()
+  -- Only in SCL files
+  local ft = vim.bo.filetype
+  if ft ~= "scl" and ft ~= "udt" and ft ~= "db" then
+    return
+  end
+
+  local bufnr = vim.api.nvim_get_current_buf()
+  local row = vim.api.nvim_win_get_cursor(0)[1]
+  local col = vim.api.nvim_win_get_cursor(0)[2]
+  local line = vim.api.nvim_buf_get_lines(bufnr, row - 1, row, false)[1]
+
+  -- Check if we just typed a space
+  if col < 1 or line:sub(col, col) ~= " " then
+    return
+  end
+
+  -- Find word before the space
+  local word_end = col - 1
+  local word_start = word_end
+  while word_start > 0 and line:sub(word_start, word_start):match("[%w_]") do
+    word_start = word_start - 1
+  end
+  word_start = word_start + 1
+
+  if word_start > word_end then
+    return
+  end
+
+  local word = line:sub(word_start, word_end)
+  local lower_word = word:lower()
+
+  -- Check if it's a keyword that needs uppercase
+  if keyword_map[lower_word] and word ~= keyword_map[lower_word] then
+    local upper_word = keyword_map[lower_word]
+    vim.api.nvim_buf_set_text(bufnr, row - 1, word_start - 1, row - 1, word_end, { upper_word })
+  end
+end
+
+-- Auto-add semicolon after END_* keywords
+local function auto_add_semicolon()
+  -- Only in SCL files
+  local ft = vim.bo.filetype
+  if ft ~= "scl" and ft ~= "udt" and ft ~= "db" then
+    return
+  end
+
+  local bufnr = vim.api.nvim_get_current_buf()
+  local row = vim.api.nvim_win_get_cursor(0)[1]
+  local line = vim.api.nvim_buf_get_lines(bufnr, row - 1, row, false)[1]
+  local trimmed = line:match("^%s*(.-)%s*$")
+
+  -- Check if line ends with an END_* keyword (without semicolon)
+  for _, end_kw in ipairs(end_keywords) do
+    if trimmed:upper() == end_kw then
+      -- Check if already has semicolon
+      if not line:match(";%s*$") then
+        local new_line = line .. ";"
+        vim.api.nvim_buf_set_lines(bufnr, row - 1, row, false, { new_line })
+        -- Move cursor to end of line
+        vim.api.nvim_win_set_cursor(0, { row, #new_line })
+      end
+      break
+    end
+  end
+end
+
 -- Setup auto-prefixing on specific triggers
 function M.setup()
   local augroup = vim.api.nvim_create_augroup("SCLAutoPrefix", { clear = true })
@@ -414,9 +497,15 @@ function M.setup()
   vim.api.nvim_create_autocmd("InsertLeave", {
     group = augroup,
     callback = function()
-      if vim.bo.filetype == "scl" then
+      local ft = vim.bo.filetype
+      if ft == "scl" or ft == "udt" or ft == "db" then
+        -- Auto-add semicolon after END_* keywords
+        auto_add_semicolon()
+        -- Variable prefixing (only for scl)
+        if ft == "scl" then
           auto_prefix_current_line()
         end
+      end
     end,
   })
 
@@ -424,14 +513,20 @@ function M.setup()
   vim.api.nvim_create_autocmd("TextChangedI", {
     group = augroup,
     callback = function()
-      if vim.bo.filetype == "scl" then
+      local ft = vim.bo.filetype
+      if ft == "scl" or ft == "udt" or ft == "db" then
         local line = vim.api.nvim_get_current_line()
         local cursor_col = vim.api.nvim_win_get_cursor(0)[2]
 
         if cursor_col > 0 and line:sub(cursor_col, cursor_col) == " " then
+          -- Auto-uppercase keywords
+          auto_uppercase_keyword()
+          -- Variable prefixing (only for scl)
+          if ft == "scl" then
             auto_prefix_current_line()
           end
         end
+      end
     end,
   })
 
@@ -484,6 +579,38 @@ function M.setup()
       end
     end,
   })
+
+  -- Auto-add semicolon when pressing Enter after END_* keyword
+  vim.api.nvim_create_autocmd("TextChangedI", {
+    group = augroup,
+    callback = function()
+      local ft = vim.bo.filetype
+      if ft ~= "scl" and ft ~= "udt" and ft ~= "db" then
+        return
+      end
+
+      local bufnr = vim.api.nvim_get_current_buf()
+      local row = vim.api.nvim_win_get_cursor(0)[1]
+      local line = vim.api.nvim_buf_get_lines(bufnr, row - 1, row, false)[1]
+
+      -- Check if we're on a new/empty line (Enter was pressed)
+      if line and line:match("^%s*$") and row > 1 then
+        local prev_line = vim.api.nvim_buf_get_lines(bufnr, row - 2, row - 1, false)[1]
+        if prev_line then
+          local trimmed = prev_line:match("^%s*(.-)%s*$")
+          -- Check if previous line is an END_* keyword without semicolon
+          for _, end_kw in ipairs(end_keywords) do
+            if trimmed:upper() == end_kw and not prev_line:match(";%s*$") then
+              -- Add semicolon to previous line
+              local new_prev = prev_line .. ";"
+              vim.api.nvim_buf_set_lines(bufnr, row - 2, row - 1, false, { new_prev })
+              break
+            end
+          end
+        end
+      end
+    end,
+  })
 end
 
 -- Manual trigger function