from random import *
from os import system, name

def clear():
    if name == 'nt':
        _ = system('cls')
    else:
        _ = system('clear')

class Square:
    def __init__(self, location, name):
        self.location = location #where the square is as an [x,y] pair
        self.x = location[0]
        self.y = location[1]
        self.state = "empty" #behind the scenes data
        self.display = " "   #what the user will see
        self.name = name     #There's gotta be a better way!

#The names of the squares are according to chess convention,
#but the coordinates are according to usual matrix notation.
a1 = Square([0,3], "a1")
a2 = Square([0,2], "a2")
a3 = Square([0,1], "a3")
a4 = Square([0,0], "a4")
b1 = Square([1,3], "b1")
b2 = Square([1,2], "b2")
b3 = Square([1,1], "b3")
b4 = Square([1,0], "b4")
c1 = Square([2,3], "c1")
c2 = Square([2,2], "c2")
c3 = Square([2,1], "c3")
c4 = Square([2,0], "c4")
d1 = Square([3,3], "d1")
d2 = Square([3,2], "d2")
d3 = Square([3,1], "d3")
d4 = Square([3,0], "d4")

board=[a1,a2,a3,a4,b1,b2,b3,b4,c1,c2,c3,c4,d1,d2,d3,d4]

setup_seed = sample(board, 4) #We pick four squares for initial amazon placement

setup_seed[0].state = "ba1" #black amazon 1
setup_seed[1].state = "ba2" #black amazon 2
setup_seed[2].state = "wa1" #white amazon 1
setup_seed[3].state = "wa2" #white amazon 2

turn = "w"  #White moves first.
turn_counter = 1

def display():   #This interprets the states of the squares for display
    global turn, turn_counter, board
    for box in board:
        if box.state == "empty":
            box.display = " "
        if box.state == "ba1":
            box.display = "B"
        if box.state == "ba2":
            box.display = "B"
        if box.state == "wa1":
            box.display = "W"
        if box.state == "wa2":
            box.display = "W"
        if box.state == "fire":
            box.display = "X"

def gui():  #This displays the board state to the user
    global turn, turn_counter, board
    clear()
    display()
    print("  a b c d")
    print("4 "+a4.display+" "+b4.display+" "+c4.display+" "+d4.display)
    print("3 "+a3.display+" "+b3.display+" "+c3.display+" "+d3.display)
    print("2 "+a2.display+" "+b2.display+" "+c2.display+" "+d2.display)
    print("1 "+a1.display+" "+b1.display+" "+c1.display+" "+d1.display)
    if turn_counter%2 == 0:
        print("It's black's turn.")
    else:
        print("It's white's turn.")

def choice_translate(box):  #Takes the string inputs of the user and outputs corresponding square
    global turn, turn_counter, board
    if box == "a1":
        return a1
    if box == "a2":
        return a2
    if box == "a3":
        return a3
    if box == "a4":
        return a4
    if box == "b1":
        return b1
    if box == "b2":
        return b2
    if box == "b3":
        return b3
    if box == "b4":
        return b4
    if box == "c1":
        return c1
    if box == "c2":
        return c2
    if box == "c3":
        return c3
    if box == "c4":
        return c4
    if box == "d1":
        return d1
    if box == "d2":
        return d2
    if box == "d3":
        return d3
    if box == "d4":
        return d4
    else:
        return False

def valid_move(start, end): #Checks to see if a mvoe is valid (for both amazons and arrows)
    global turn, turn_counter, board

    test_set=[] #This will be the set of squares between the start and end of the move.
    #For reasons unknown, the test set always finds each eligible square twice. How to fix?

    #There are three reasons to immediately reject a move:
    if end.state != "empty": #If the ending square isn't empty
        return False
    if start == end: #If the ending square is the starting square
        return False
    #If the start and end aren't in the same row, column, or diagonal.
    if (start.x != end.x) and (start.y != end.y) and (abs(start.x - end.x) != abs(start.y - end.y)):
        return False

    #If they are in the same column...
    if start.x == end.x:
        if start.y > end.y: #If we are going down....
            for box in board:  #...find the squares...
                if box.x == start.x:  #...in that column...
                    for i in range(1, abs(start.y-end.y)):  #... between the start and end...
                        if box.y == start.y-i:
                            test_set.append(box)  #... and add it to the list.
        if start.y < end.y: #If we are going up... etc...
            for box in board:
                if box.x == start.x:
                    for i in range(1, abs(start.y-end.y)):
                        if box.y == start.y+i:
                            test_set.append(box)

    #If they are in the same row...
    if start.y == end.y:
        if start.x > end.x: #going right....
            for box in board:
                if box.y == start.y:
                    for i in range(1, abs(start.x-end.x)):
                        if box.x == start.x-i:
                            test_set.append(box)
        if start.x < end.x: #going left...
            for box in board:
                if box.y == start.y:
                    for i in range(1, abs(start.x-end.x)):
                        if box.x == start.x+i:
                            test_set.append(box)

    #If they are on the same diagonal
    if abs(start.x - end.x) == abs(start.y - end.y):
        if (start.x < end.x) and (start.y < end.y): #going up and right
            for box in board:
                for i in range(1, abs(start.x-end.x)):
                    if ((box.x == start.x+i) and (box.y == start.y+i)):
                        test_set.append(box)
        if (start.x > end.x) and (start.y > end.y): #going down and left
            for box in board:
                for i in range(1, abs(start.x-end.x)):
                    if ((box.x == start.x-i) and (box.y == start.y-i)):
                        test_set.append(box)
        if (start.x > end.x) and (start.y < end.y): #going up and left
            for box in board:
                for i in range(1, abs(start.x-end.x)):
                    if ((box.x == start.x-i) and (box.y == start.y+i)):
                        test_set.append(box)
        if (start.x < end.x) and (start.y > end.y): #going down and right
            for box in board:
                for i in range(1, abs(start.x-end.x)):
                    if ((box.x == start.x+i) and (box.y == start.y-i)):
                        test_set.append(box)

    for test in test_set: #now make sure all of the squares we've selected are indeed empty
        if test.state != "empty":
            return False
    return True

def possible_moves(amazon):  #outputs a list of squares that can be reached by an amazon
    moves=[]
    for box in board:
        if valid_move(amazon, box):
            moves.append(box)
    return(moves)

def play():
    global turn, turn_counter, board
    gui()

    #We check which amazons can legally move
    movable_amazons=[]
    for box in board:
        if box.state == turn+"a1":
            if len(possible_moves(box)) != 0:
                movable_amazons.append(box.name)
        if box.state == turn+"a2":
            if len(possible_moves(box)) != 0:
                movable_amazons.append(box.name)

    #If none can move, then the game is over!
    if len(movable_amazons)==0:
        if turn_counter%2 == 0:
            input("White wins!")
            exit(0)
        if turn_counter%2 == 1:
            input("Black wins!")
            exit(0)

    #Otherwise, the player chooses an amazon to move
    if len(movable_amazons) == 2: #If both can move they have a choice
        amazon_choice = input("Choose a square containing one of your amazons, either "+movable_amazons[0]+" or "+movable_amazons[1]+": ")
        while amazon_choice not in movable_amazons:
            amazon_choice = input("That's not one of the options. Try again: ")
    if len(movable_amazons) == 1: #If only one can move, they have no choice
        amazon_choice = movable_amazons[0]
    gui()

    #The player chooses a square to move to
    print("You must move the amazon on "+amazon_choice+". Choose the square you want to move to.")
    print("Which of the following would you like to move to?")
    amazon_choice = choice_translate(amazon_choice)
    choices = []  #We have a list to display to the user...
    for option in possible_moves(amazon_choice):  #...consisting of their possible moves.
        choices.append(option.name)
    move_choice = choice_translate(input(choices))

    #The following three while statements only catch exemptions if made in this order.
    #So if the user first inputs a square correctly, but it's not a possible move,
    #and then they enter in gibberish, it wigs out. How to fix?
    while move_choice == False: #choice_translate outputs False when the input isn't a square name
        move_choice = choice_translate(input("That's not a valid move. Try again: "))
    while move_choice.name not in choices:
        move_choice = choice_translate(input("That's not an option. Try again: "))
    while valid_move(amazon_choice, move_choice) == False:
        move_choice = choice_translate(input("That amazon can't move there. Try again: "))

    #If all goes well, we make the move by changing the states of the squares.
    if valid_move(amazon_choice, move_choice):
        move_choice.state = amazon_choice.state
        amazon_choice.state = "empty"
    gui()

    #The player chooses a square to shoot
    choices = []
    for option in possible_moves(move_choice):
        choices.append(option.name)
    print("Choose the square you want to set aflame: ")
    burn_choice = choice_translate(input(choices))

    #These three statements have the same problem as those above.
    while burn_choice == False:
        burn_choice = choice_translate(input("That's not the name of any square. Try again: "))
    while burn_choice.state != "empty":
        burn_choice = choice_translate(input("That's square isn't empty. Try again: "))
    while valid_move(move_choice, burn_choice) == False:
        burn_choice = choice_translate(input("You can't shoot there. Try again: "))
    burn_choice.state = "fire"

    #Bookkeepping for turn taking
    turn_counter+=1
    if turn_counter%2 == 0:
        turn = "b"
    if turn_counter%2 == 1:
        turn = "w"

while True:
    play()


#Next Steps:
    #have students change the abilities of the amazons, size of the board, etc.
    #Add a class to record game state!?!?!?