{
 "metadata": {
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.7.3-final"
  },
  "orig_nbformat": 2,
  "kernelspec": {
   "name": "python3",
   "display_name": "Python 3.7.3 64-bit ('python': venv)",
   "metadata": {
    "interpreter": {
     "hash": "d99f099520c2505e9f745916a84fcd3ec6a6f02f993bb8e12b586a85fced6daa"
    }
   }
  }
 },
 "nbformat": 4,
 "nbformat_minor": 2,
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import random"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "random.seed()\n",
    "\n",
    "BOARD_WIDTH = 10\n",
    "BOARD_HEIGHT = 10\n",
    "\n",
    "def random_x_y():\n",
    "    x = random.randrange(1,BOARD_WIDTH+1)\n",
    "    y = random.randrange(1,BOARD_HEIGHT+1)\n",
    "    return (x,y)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "5 2\n"
     ]
    }
   ],
   "source": [
    "x,y = random_x_y()\n",
    "print (x,y)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [],
   "source": [
    "def random_direction(valid_directions):\n",
    "    idx = random.ran range(len(valid_directions))\n",
    "    return valid_directions[idx]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "1\n"
     ]
    }
   ],
   "source": [
    "print(random_direction([0,1,2]))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [],
   "source": [
    "SHIPS = [ (\"BATTLESHIP\", 5),\n",
    "          (\"CRUISER\", 3),\n",
    "          (\"DESTROYER<A>\", 2),\n",
    "          (\"DESTROYER<B>\", 2) ]\n",
    "\n",
    "# given a coordinate (x,y) and a ship type,\n",
    "# determine which directions from the coordinate \n",
    "# a ship could be placed. Directions are numbered\n",
    "# starting at 0 for up, 1 for up/right, 2 for right, \n",
    "# etc., clockwise from zero (12 o'clock position)\n",
    "# returns a vector of direction numbers where\n",
    "# a ship can be placed, starting at one end of the\n",
    "# ship to its length\n",
    "def get_possible_directions(x,y,ship):\n",
    "    ship_len = SHIPS[ship][1] - 1\n",
    "    dirs = [False for x in range(8)]\n",
    "    dirs[0] = (x - ship_len) >=1\n",
    "    dirs[2] = (y + ship_len) <= BOARD_WIDTH\n",
    "    dirs[1] = dirs[0] and dirs[2]\n",
    "    dirs[4] = (x + ship_len) <= BOARD_HEIGHT\n",
    "    dirs[3] = dirs[2] and dirs[4]\n",
    "    dirs[6] = (y - ship_len) >= 1\n",
    "    dirs[5] = dirs[4] and dirs[6]\n",
    "    dirs[7] = dirs[6] and dirs[0]\n",
    "\n",
    "    return [x for x in range(len(dirs)) if dirs[x]]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "Boundary Conditions\n( 5, 5): [0, 1, 2, 3, 4, 5, 6, 7]\n( 1, 1): [2, 3, 4]\n( 1,10): [4, 5, 6]\n(10,10): [0, 6, 7]\n(10, 1): [0, 1, 2]\n"
     ]
    }
   ],
   "source": [
    "print(\"Boundary Conditions\")\n",
    "print(\"( 5, 5):\",get_possible_directions(5,5,0))\n",
    "print(\"( 1, 1):\",get_possible_directions(1,1,0))\n",
    "print(\"( 1,10):\",get_possible_directions(1,10,0))\n",
    "print(\"(10,10):\",get_possible_directions(10,10,0))\n",
    "print(\"(10, 1):\",get_possible_directions(10,1,0))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "VALID_MOVES = [[-1, 0],\n",
    "               [-1, 1],\n",
    "               [ 0, 1],\n",
    "               [ 1, 1],\n",
    "               [ 1, 0],\n",
    "               [ 1,-1],\n",
    "               [ 0,-1],\n",
    "               [-1,-1]]\n",
    "\n",
    "\n",
    "def generate_ship_coordinates(x_start,y_start,direction,ship):\n",
    "    ship_len = SHIPS[ship][1] - 1\n",
    "    d_x = VALID_MOVES[direction][0]\n",
    "    d_y = VALID_MOVES[direction][1]\n",
    "\n",
    "    coords = [(x_start,y_start)]\n",
    "    x_coord = x_start\n",
    "    y_coord = y_start\n",
    "    for i in range(ship_len):\n",
    "        x_coord = x_coord + d_x\n",
    "        y_coord = y_coord + d_y\n",
    "        coords.append((x_coord,y_coord))\n",
    "    return coords"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "('BATTLESHIP', 5) 5 7 6 [(5, 7), (5, 6), (5, 5), (5, 4), (5, 3)]\n('CRUISER', 3) 1 3 3 [(1, 3), (2, 4), (3, 5)]\n('DESTROYER<A>', 2) 5 9 6 [(5, 9), (5, 8)]\n('DESTROYER<B>', 2) 3 4 3 [(3, 4), (4, 5)]\n"
     ]
    }
   ],
   "source": [
    "\n",
    "for ship in range(len(SHIPS)):\n",
    "    x,y = random_x_y()\n",
    "    directions = get_possible_directions(x,y,ship)\n",
    "    direction = random_direction(directions)\n",
    "    coords = generate_ship_coordinates(x,y,direction,ship)\n",
    "    print(SHIPS[ship],x,y,direction,coords)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
 ]
}