From 540b6b763a3639fb85451b3c500f271fca54ba6c Mon Sep 17 00:00:00 2001
From: Todd Kaiser <marvin826@comcast.net>
Date: Sun, 7 Mar 2021 18:31:24 -0700
Subject: [PATCH] Initial version of the salvo.py program. Added initial user
 input functions for ship coordinates.

---
 77 Salvo/python/salvo.py | 82 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 77 Salvo/python/salvo.py

diff --git a/77 Salvo/python/salvo.py b/77 Salvo/python/salvo.py
new file mode 100644
index 00000000..3d36dcbd
--- /dev/null
+++ b/77 Salvo/python/salvo.py	
@@ -0,0 +1,82 @@
+import re
+
+# declare static variables
+BOARD_WIDTH = 10
+BOARD_HEIGHT = 10
+
+SHIPS = [("BATTLESHIP", 5),
+         ("CRUISER", 3),
+         ("DESTROYER<A>", 2),
+         ("DESTROYER<B>", 2)]
+
+VALID_MOVES = [[-1, 0],
+               [-1, 1],
+               [0, 1],
+               [1, 1],
+               [1, 0],
+               [1, -1],
+               [0, -1],
+               [1, -1]]
+
+COORD_REGEX = '[ \t]{0,}(-?[0-9]{1,3})[ \t]{0,},[ \t]{0,}(-?[0-9]{1,2})'
+
+
+# input_coord
+#
+# ask user for single (x,y) coordinate
+# validate the coordinates are within the bounds
+# of the board width and height. mimic the behavior
+# of the original program which exited with error
+# messages if coordinates where outside of array bounds.
+# if input is not numeric, print error out to user and
+# let them try again.
+def input_coord():
+    match = None
+    while not match:
+        coords = input("? ")
+        match = re.match(COORD_REGEX, coords)
+        if not match:
+            print("!NUMBER EXPECTED - RETRY INPUT LINE")
+    x = int(match.group(1))
+    y = int(match.group(2))
+
+    if x > BOARD_HEIGHT or y > BOARD_WIDTH:
+        print("!OUT OF ARRAY BOUNDS IN LINE 1540")
+        exit()
+
+    if x <= 0 or y <= 0:
+        print("!NEGATIVE ARRAY DIM IN LINE 1540")
+        exit()
+
+    return x, y
+
+
+# input_ship_coords
+#
+# ask the user for coordinates for each
+# ship on their board. uses input_coord()
+# to read each coord.
+# returns an array of arrays, one array for
+# each ship's coordinates, which is an array 
+# of (x,y) sets.
+def input_ship_coords():
+    print("ENTER COORDINATES FOR...")
+
+    coords = []
+    for ship in SHIPS:
+        print(ship[0])
+        list = []
+        for i in range(ship[1]):
+            x, y = input_coord()
+            list.append((x, y))
+        coords.append(list)
+    return coords
+
+
+# print out the title 'screen'
+print('{0:>38}'.format("SALVO"))
+print('{0:>57s}'.format("CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY"))
+print('\n\n')
+
+# ask the user for ship coordinates
+coords = input_ship_coords()