Solve the klotski (sliding block) puzzle by moving the red block to the marked area.
Released under MIT license. You know, because I didn't invent klotski.
Status : /web/client_server - inactive (80%) /web/standalone_js - complete
standalone_js: open /web/standalone_js/klotski.html , play.
client_server: Compile and run jar from /src (server runs the game), open /web/client_server/drawKlot.html (client presents the game) , play. build.gradle included for your convenience.
Dependencies - TooTallNate websockets 1.3 and Gson 2.8
W A S D or arrow keys to move the cursor. Hold down shift to move the shape beneath it, when the way is clear.
Tests
Virtually nothing tests itself or is tested. Partly this stems from a non-functional orientation. Nevertheless, Board - serialize, deserialize, in_goal_area, swap_block, try_cursor, try_block, and all the internal functions still need confirming tests. Screen, mercifully, seems testable by eye.
Invalid move
It could be cool to show when the cursor is trying to move in a direction it can't. I considered drawing a red bar that fades with a timer. But then I'd have to figure out the edge of the shape it's under in that direction.
Wiki
I like the idea of literate programming. But, it is only appropriate after the program is done. I could enliterate this, but would probably refactor it again before I did.
Hint system
I think there's one way of solving the puzzle, with symmetric variations. So, it is possible to have a solver calculate the moves (pdf) via a depth-first search. Then it could make a suggestion for the next move or something. What would be really fancy is a segmented arrow showing a four move path or something. Both sound like a lot of work.