fix(formatter): Fix multi-line condition and END_IF indentation

- Multi-line IF conditions: continuation lines at +1 from IF
- END_IF now decreases indent (reverted previous wrong change)
- Track multi-line condition state separately from THEN tracking
- Now matches TIA Portal expected format

src/formatter.lua

@@ -67,7 +67,7 @@ function M.format_document(content, options)
   local in_var_section = false
   local in_code_section = false
   local prev_line_keyword = nil
-  local prev_line_had_then = true  -- Track if previous line had THEN
+  local in_multi_line_condition = false  -- Track if we're in multi-line IF condition
   
   -- FB call continuation tracking
   local in_fb_call = false
@@ -286,11 +286,7 @@ function M.format_document(content, options)
           if_base_level = nil
         end
         in_fb_call = false  -- Reset FB call state
-        -- Don't decrease indent for END_IF - it stays at same level as content (per TIA Portal)
-        -- Only decrease for other enders like END_REGION, END_CASE, END_FOR, etc.
-        if kw ~= "END_IF" then
-          indent_level = math.max(0, indent_level - 1)
-        end
+        indent_level = math.max(0, indent_level - 1)
         if needs_semicolon(trimmed) then
           formatted_line = formatted_line .. ";"
         end
@@ -322,25 +318,40 @@ function M.format_document(content, options)
           -- Check if THEN is on the same line
           if trimmed:match("THEN%s*$") then
             if_base_level = indent_level
-            prev_line_had_then = true
+            in_multi_line_condition = false
             indent_level = indent_level + 1
           else
             -- THEN on separate line, don't increase yet
             if_base_level = indent_level
-            prev_line_had_then = false
+            in_multi_line_condition = true
           end
         elseif kw == "THEN" then
-          -- THEN on its own line, increase for content
-          prev_line_had_then = true
+          -- THEN on its own line, increase for content and exit multi-line condition
+          in_multi_line_condition = false
           indent_level = indent_level + 1
         else
           -- For other block starters (FOR, WHILE, REGION, CASE), always increase
-          prev_line_had_then = true
+          in_multi_line_condition = false
           indent_level = indent_level + 1
         end
         table.insert(formatted_lines, formatted_line)
       -- Regular line
       else
+        -- Handle multi-line condition continuation
+        local use_multi_line_indent = false
+        if in_multi_line_condition and kw ~= "THEN" then
+          -- This is a continuation of a multi-line IF condition
+          -- Use +1 indent from IF level
+          use_multi_line_indent = true
+          in_multi_line_condition = false  -- Exit multi-line mode after first continuation
+        end
+        
+        if use_multi_line_indent then
+          formatted_line = string.rep(indent_char, (indent_level + 1) * indent_size) .. trimmed
+        else
+          formatted_line = get_indent() .. trimmed
+        end
+        
         if needs_semicolon(trimmed) and not in_fb_call then
           formatted_line = formatted_line .. ";"
         end
@@ -349,10 +360,6 @@ function M.format_document(content, options)
     end
 
     prev_line_keyword = kw
-    -- Reset THEN tracking for next iteration (unless current line has THEN)
-    if kw ~= "THEN" then
-      prev_line_had_then = true
-    end
   end
 
   local result = table.concat(formatted_lines, "\n")