window.rb in ruco-0.0.41

- old
+ new

@@ -1,35 +1,56 @@
 module Ruco
   class Window
     OFFSET = 5
 
-    attr_accessor :position, :lines, :columns, :top, :left
-    attr_reader :cursor
+    attr_accessor :lines, :columns, :left
+    attr_reader :cursor, :top
 
-    def initialize(lines, columns)
+    def initialize(lines, columns, options={})
+      @options = options
+
+      @options[:line_scroll_threshold] ||= 1
+      @options[:line_scroll_offset] ||= 1
+      @options[:column_scroll_threshold] ||= 1
+      @options[:column_scroll_offset] ||= 5
+
       @lines = lines
       @columns = columns
       @top = 0
       @left = 0
       @cursor = Position.new(0,0)
     end
 
-    def crop(content)
-      lines = content[visible_lines] || []
-      lines[@lines-1] ||= nil
-      lines.map do |line|
+    def position=(x)
+      set_position(x)
+    end
+
+    def set_position(position, options={})
+      scroll_line_into_view position.line, (options[:max_lines] || 9999)
+      scroll_column_into_view position.column
+      @cursor = Position.new(position.line - @top, position.column - @left)
+    end
+
+    def crop(lines)
+      lines_to_display = lines[visible_lines] || []
+      lines_to_display[@lines-1] ||= nil
+      lines_to_display.map do |line|
         line ||= ''
         line[visible_columns] || ''
       end
     end
 
-    def position=(pos)
-      self.top = pos.line - line_offset unless visible_lines.include?(pos.line)
-      self.left = pos.column - column_offset  unless visible_columns.include?(pos.column)
-      @cursor = Position.new(pos.line - @top, pos.column - @left)
+    def scroll_line_into_view(line, total_lines)
+      result = adjustment(line, visible_lines, @options[:line_scroll_threshold], @options[:line_scroll_offset])
+      set_top result, total_lines if result
     end
 
+    def scroll_column_into_view(column)
+      result = adjustment(column, visible_columns, @options[:column_scroll_threshold], @options[:column_scroll_offset])
+      self.left = result if result
+    end
+
     def color_mask(selection)
       mask = Array.new(lines)
       return mask unless selection
 
       mask.map_with_index do |_,line|
@@ -44,33 +65,35 @@
           [last[1]-left, Curses::A_NORMAL]
         ]
       end
     end
 
-    def top=(x)
-      @top = [x,0].max
-    end
-
     def left=(x)
       @left = [x,0].max
     end
 
+    def set_top(line, total_lines)
+      max_top = total_lines - lines + 1 + @options[:line_scroll_offset]
+      @top = [[line, max_top].min, 0].max
+    end
+
     private
 
+    def adjustment(current, allowed, threshold, offset)
+      if current < (allowed.first + threshold)
+        current - offset
+      elsif current > (allowed.last - threshold)
+        size = allowed.last - allowed.first + 1
+        current - size + 1 + offset
+      end
+    end
+
     def visible_area(line)
       line += @top
       start_of_line = [line, @left]
       last_visible_column = @left + @columns
       end_of_line = [line, last_visible_column]
       start_of_line..end_of_line
-    end
-
-    def line_offset
-      @lines / 2
-    end
-
-    def column_offset
-      @columns / 2
     end
 
     def visible_lines
       @top..(@top+@lines-1)
     end
\ No newline at end of file