Support table and table column sizing

lib/notare/width_parser.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module Notare
+  module WidthParser
+    TWIPS_PER_INCH = 1440
+    TWIPS_PER_CM = 567
+    PCT_MULTIPLIER = 50
+
+    ParsedWidth = Struct.new(:value, :type, keyword_init: true)
+
+    def self.parse(value)
+      case value
+      when :auto, nil
+        ParsedWidth.new(value: 0, type: "auto")
+      when Integer
+        ParsedWidth.new(value: value, type: "dxa")
+      when /\A(\d+(?:\.\d+)?)\s*in\z/i
+        twips = (::Regexp.last_match(1).to_f * TWIPS_PER_INCH).to_i
+        ParsedWidth.new(value: twips, type: "dxa")
+      when /\A(\d+(?:\.\d+)?)\s*cm\z/i
+        twips = (::Regexp.last_match(1).to_f * TWIPS_PER_CM).to_i
+        ParsedWidth.new(value: twips, type: "dxa")
+      when /\A(\d+(?:\.\d+)?)\s*%\z/
+        pct = (::Regexp.last_match(1).to_f * PCT_MULTIPLIER).to_i
+        ParsedWidth.new(value: pct, type: "pct")
+      else
+        raise ArgumentError, "Invalid width: #{value}. Use '2in', '5cm', '50%', :auto, or integer twips."
+      end
+    end
+  end
+end