fix: correctly indent IF/ELSIF condition continuations

- Add in_condition state to track when inside IF/ELSIF condition (before THEN)
- Use condition_indent for continuation lines in conditions
- Fixes multiline IF/ELSIF conditions being incorrectly indented

src/formatter.lua

@@ -316,6 +316,8 @@ function M.format_document(content, options)
   
   local in_assignment = false
   local assignment_continuation_indent = ""
+  local in_condition = false
+  local condition_indent = ""
 
   for line_num, line in ipairs(lines) do
     local trimmed = line:gsub("^%s+", ""):gsub("%s+$", "")
@@ -337,6 +339,21 @@ function M.format_document(content, options)
     -- Check if this line ends an assignment (has := and ends with ;)
     local ends_assignment = trimmed:match(":=") and trimmed:match(";%s*$")
 
+    -- Check if continuing condition (IF/ELSIF condition before THEN)
+    if in_condition and not ends_assignment then
+      local starts_with_operator = is_assignment_continuation(trimmed)
+      local first_word = trimmed:match("^([%w_]+)")
+      local is_then = first_word and first_word:upper() == "THEN"
+      if starts_with_operator or is_then then
+        table.insert(formatted_lines, condition_indent .. trimmed)
+        if is_then then
+          in_condition = false
+        end
+        goto continue
+      end
+      in_condition = false
+    end
+
     -- Check if continuing assignment
     -- Continuation if: in assignment AND (starts with operator OR doesn't start new statement)
     -- BUT NOT if this line ends an assignment OR starts a new assignment (contains :=) OR starts with block ender
@@ -471,6 +488,7 @@ function M.format_document(content, options)
         end
         table.insert(formatted_lines, formatted)
         table.insert(stack, { type = "THEN_CONTENT", indent = #stack, no_indent = true })
+        in_condition = false
       elseif kw == "ELSE" or kw == "ELSIF" then
         if #stack > 0 and stack[#stack].type == "THEN_CONTENT" then
           table.remove(stack)
@@ -521,6 +539,10 @@ function M.format_document(content, options)
       local formatted = string.rep(indent_char, current_level) .. trimmed
       table.insert(formatted_lines, formatted)
       table.insert(stack, { type = kw, indent = current_level })
+      if kw == "IF" or kw == "ELSIF" then
+        in_condition = true
+        condition_indent = string.rep(indent_char, current_level)
+      end
       goto continue
     end