#!/usr/bin/clisp
;;;;
;;;; Terra Nostra is a Minecraft-like survival game for the commandline.
;;;; 
;;;; (c) 2018 Daniel Vedder
;;;;

;;(load "util.lisp") ;; I want to avoid using this if possible

(defvar *world* NIL)

(defstruct patch
	(pos '(0 0)) ;position
	(alt 0) ;altitude
	(streams-in NIL)
	(streams-out NIL))

(defun init-matrix (size)
	"Create a square matrix of empty patches"
	(do ((y 0 (1+ y)) (world NIL) (row NIL NIL))
		((= y size) world)
		(dotimes (x size)
			(setf row (append row (list (make-patch :pos (list x y))))))
		(setf world (append world (list row)))))

(defun coord (x y &optional (world *world*))
	"Return the patch at the given coordinates or NIL if out of bounds"
	(unless (or (< x 0) (< y 0) (> x (length world)) (> y (length world)))
		(nth x (nth y world))))

(defun save-topography (file-name &optional (world *world*))
	"Save the world topography as a csv file"
	(with-open-file (tf file-name :direction :output)
		(dolist (row world)
			;; XXX This would be quicker with (string-from-list), but I
			;; don't want to use util.lisp just yet
			(do ((x 0 (1+ x)) (xstr ""))
				((= x (length world)) (format tf "~&~S~%" xstr))
				(setf xstr (concatenate 'string xstr (unless (= x 0) ",")
							   (format NIL "~S" (patch-alt (nth x row)))))))))

(defun create-mountains (world &optional (montaneity 2))
	"Create mountains and hills. Montaneity determines their number and height."
	)

(defun create-valleys (world &optional (aqueousness 5))
	"Create valleys through streams. Aqueousness determines their number."
	)