Resizable window - just patch existing code, Linux

I need you to enhance FluxBox window manager for Linux to make windows resizable by dragging borders. Currently fluxbox already allows resizing of windows by dragging grip elements which are at the bottom of the window (in left and right corner). I need you to extend this functionality, to code support for window resizing when window border is dragged. Your task will be split into several sub-goals: goal 1: show proper resize-cursors when mouse is over the edge (window border), depending on if mouse is over left/right border, top/bottom border, or corners. goal 2: dragging to actually resize If you have questions, feel free to PM me. Thank you