A window manager takes care of the details of creating, displaying, moving, and resizing a collection of windows in a graphical user interface. It also handles input events (like mouse clicks) related to these window management tasks. Your project is to write a WIndow Manager Program (WIMP). The WIMP controls a screen of size 1024 × 1024 (measured in pixels), with the upper left-hand pixel at (0, 0). The x-coordinates range from 0 at the left edge of the screen to 1023 at the right edge, and the y-coordinates range from 0 at the top of the screen to 1023 at the bottom. All coordinates are integers. The user can create and manipulate rectangular windows by moving the mouse and clicking the mouse button. A window has 4 distinct areas: Area Close box Zoom box Motion bar Data area Location and Size upper left hand corner of the window (25 × 25 pixels) upper right hand corner of the window (25 × 25 pixels) fills the top 25 pixels of the window, excluding zoom and close boxes remainder of the window A window will always be at least 51 × 26 so that all four areas are nonempty. Each window is assigned a unique integer identifier, starting at 0 (the first window created has id 0, the second one created has id 1, and so on). Identifiers are not reused. The WIMP accepts the following events: Event Meaning user pressed mouse button at location (x, y) user released mouse button at location (x, y) user moved mouse to location (x, y) create new window with positions left, top, right, and bottom redraw all windows from back to front exit the WIMP DN UP AT CR RE ZZ The values x, The CR event event they must be redrawn from back (least recently on top) to front (most recently on top). This ensures that they appear correctly overlapped to the user. It is the job of the WIMP to keep track of all windows, even if some are overlapping. The rules it uses are:
2/3 5. Zooming is a toggle that either makes the window occupy the entire screen, or returns the window to its initial size. 6. A DN event in the motion bar allows the window to be relocated. The motion stops with an UP event. The window moves the same distance and direction that the mouse moved between the DN and UP events. 7. AT events while moving a window must output the window’s current position. AT events at any other time do not generate any output. 8. Windows occupying the full screen cannot be moved. 9. Windows can partially move off the visible screen. 10. AT events happen. Input The input file contains one or more lines, each of which contains a single event. A ZZ event signals the end of the input. The events are all part of the same session. Output For each user action, output the corresponding message. On an RE event, the location of all windows must be output from back-to-front using the format shown. Action Message Create window ‘Created window n at l, t, r, b’ Sample Input CR 0 0 200 200 CR 50 50 250 250 RE DN 195 5 AT 50 50 UP 198 6 AT 100 100 AT 1000 1000 DN 1020 10 UP 1020 10 RE DN 100 100 UP 800 0 DN 0 700 UP 1023 1023 DN 50 10 AT 70 70 UP 100 100 Select window Close window Move window Zoom window Redraw ‘Selected window n’ ‘Closed window n’ ‘Moved window n to l, t, r, b’ ‘Resized window n to l, t, r, b’ ‘Window n at l, t, r, b’
3/3 DN 60 60 UP 60 60 RE ZZ Sample Output Created window 0 at 0, 0, 200, 200 Created window 1 at 50, 50, 250, 250 Window 0 at 0, 0, 200, 200 Window 1 at 50, 50, 250, 250 Selected window 0 Resized window 0 to 0, 0, 1023, 1023 Selected window 0 Resized window 0 to 0, 0, 200, 200 Window 1 at 50, 50, 250, 250 Window 0 at 0, 0, 200, 200 Selected window 0 Selected window 0 Moved window 0 to 20, 60, 220, 260 Moved window 0 to 50, 90, 250, 290 Selected window 1 Closed window 1 Window 0 at 50, 90, 250, 290