#!/usr/bin/python3

import curses
import math
import os
import signal
import time


def set_window_geometries():

    def set_window_size():
        win["size"], win["start"] = [0, 0], [0, 0]
        win["size"][0] = win["config"][0]
        if (win["config"][0] == 0):
            win["size"][0] = screen_size[0] - sep_size
        elif (win["config"][0] < 0):
            win["size"][0] = screen_size[0] + win["config"][0] - sep_size
        win["size"][1] = win["config"][1]
        if (win["config"][1] == 0):
            win["size"][1] = screen_size[1]
        elif (win["config"][1] < 0):
            win["size"][1] = screen_size[1] + win["config"][1]

    def place_window():
        win_i = windows.index(win)

        # If win is first window, it goes into the top left corner.
        win["start"][0] = 0 + sep_size
        win["start"][1] = 0
        if (win_i > 0):

            # If not, get win's closest predecessor starting a new stack on the
            # screen top,fit win's top left to that win_top's top right corner.
            win_top = None
            for i in range(win_i - 1, -1, -1):
                win_top = windows[i]
                if (win_top["start"][0] == 0 + sep_size):
                    break
            win["start"][1] = win_top["start"][1] + win_top["size"][1] \
                + sep_size

            # If enough space is found below win's predecessor, fit win's top
            # left corner to that predecessor's bottom left corner.
            win_prev = windows[win_i - 1]
            next_free_y = win_prev["start"][0] + win_prev["size"][0] + sep_size
            if (win["size"][1] <= win_prev["size"][1] and
                    win["size"][0] <= screen_size[0] - next_free_y):
                win["start"][1] = win_prev["start"][1]
                win["start"][0] = next_free_y

            # If that fails, try to fit win's top left corner to the top right
            # corner of its closest predecessor win_test 1) below win_top (see
            # above) 2) and with enough space open to its right between its
            # right edge and the lower edge of a win_high located directly
            # above win_test to fit win there (without growing further to the
            # right than win_high does or surpassing the screen's lower edge).
            else:
                win_test = win_prev
                win_high = None
                while (win_test != win_top):
                    for i in range(win_i - 2, -1, -1):
                        win_high = windows[i]
                        if win_test["start"][0] > win_high["start"][0]:
                            break
                    next_free_y = win_high["start"][0] + win_high["size"][0] \
                        + sep_size
                    first_free_x = win_test["start"][1] + win_test["size"][1] \
                        + sep_size
                    last_free_x = win_high["start"][1] + win_high["size"][1]
                    if (win["size"][0] <= screen_size[0] - next_free_y and
                            win["size"][1] <= last_free_x - first_free_x):
                        win["start"][1] = first_free_x
                        win["start"][0] = next_free_y
                        break
                    win_test = win_high

    global screen_size, stdscr
    curses.endwin()
    stdscr = curses.initscr()
    screen_size = stdscr.getmaxyx()
    for win in windows:
        set_window_size()
        place_window()
    cursed_main.redraw = True


def draw_screen():

    def healthy_addch(y, x, char, attr=0):
        """Workaround for <http://stackoverflow.com/questions/7063128/>."""
        if y == screen_size[0] - 1 and x == screen_size[1] - 1:
            char_before = stdscr.inch(y, x - 1)
            stdscr.addch(y, x - 1, char, attr)
            stdscr.insstr(y, x - 1, " ")
            stdscr.addch(y, x - 1, char_before)
        else:
            stdscr.addch(y, x, char, attr)

    def draw_window_border_lines():
        for win in windows:
            for k in range(2):
                j = win["start"][int(k == 0)] - sep_size
                if (j >= 0 and j < screen_size[int(k == 0)]):
                    start = win["start"][k]
                    end = win["start"][k] + win["size"][k]
                    end = end if end < screen_size[k] else screen_size[k]
                    if k:
                        [healthy_addch(j, i, '-') for i in range(start, end)]
                    else:
                        [healthy_addch(i, j, '|') for i in range(start, end)]

    def draw_window_border_corners():
        for win in windows:
            up = win["start"][0] - sep_size
            down = win["start"][0] + win["size"][0]
            left = win["start"][1] - sep_size
            right = win["start"][1] + win["size"][1]
            if (up >= 0 and up < screen_size[0]):
                if (left >= 0 and left < screen_size[1]):
                    healthy_addch(up, left, '+')
                if (right >= 0 and right < screen_size[1]):
                    healthy_addch(up, right, '+')
            if (down >= 0 and down < screen_size[0]):
                if (left >= 0 and left < screen_size[1]):
                    healthy_addch(down, left, '+')
                if (right >= 0 and right < screen_size[1]):
                    healthy_addch(down, right, '+')

    def draw_window_titles():
        for win in windows:
            title = " " + win["title"] + " "
            if len(title) <= win["size"][1]:
                y = win["start"][0] - 1
                start_x = win["start"][1] + int((win["size"][1] \
                    - len(title))/2)
                for x in range(len(title)):
                    healthy_addch(y, start_x + x, title[x])

    def draw_window_contents():
        def draw_winmap():
            """Draw winmap in area delimited by offset, winmap_size.

            The individuall cell of a winmap is interpreted as either a single
            character element, or as a tuple of character and attribute,
            depending on the size len(cell) spits out.
            """
            stop = [0, 0]
            for i in range(2):
                stop[i] = win["size"][i] + offset[i]
                if stop[i] >= winmap_size[i]:
                    stop[i] = winmap_size[i]
            for y in range(offset[0], stop[0]):
                for x in range(offset[1], stop[1]):
                    cell = winmap[y * winmap_size[1] + x]
                    attr = 0
                    if len(cell) > 1:
                        attr = cell[1]
                        cell = cell[0]
                    y_in_screen = win["start"][0] + (y - offset[0])
                    x_in_screen = win["start"][1] + (x - offset[1])
                    if (y_in_screen < screen_size[0]
                            and x_in_screen < screen_size[1]):
                        healthy_addch(y_in_screen, x_in_screen, cell, attr)
        def draw_scroll_hints():
            def draw_scroll_string(n_lines_outside):
                hint = ' ' + str(n_lines_outside + 1) + ' more ' + unit + ' '
                if len(hint) <= win["size"][ni]:
                    non_hint_space = win["size"][ni] - len(hint)
                    hint_offset = int(non_hint_space / 2)
                    for j in range(win["size"][ni] - non_hint_space):
                        pos_2 = win["start"][ni] + hint_offset + j
                        x, y = (pos_2, pos_1) if ni else (pos_1, pos_2)
                        healthy_addch(y, x, hint[j], curses.A_REVERSE)
            def draw_scroll_arrows(ar1, ar2):
                for j in range(win["size"][ni]):
                    pos_2 = win["start"][ni] + j
                    x, y = (pos_2, pos_1) if ni else (pos_1, pos_2)
                    healthy_addch(y, x, ar1 if ni else ar2, curses.A_REVERSE)
            for i in range(2):
                ni = int(i == 0)
                unit = 'rows' if ni else 'columns'
                if (offset[i] > 0):
                    pos_1 = win["start"][i]
                    draw_scroll_arrows('^', '<')
                    draw_scroll_string(offset[i])
                if (winmap_size[i] > offset[i] + win["size"][i]):
                    pos_1 = win["start"][i] + win["size"][i] - 1
                    draw_scroll_arrows('v', '>')
                    draw_scroll_string(winmap_size[i] - offset[i]
                        - win["size"][i])
        for win in windows:
            offset, winmap_size, winmap = win["func"]()
            draw_winmap()
            draw_scroll_hints()

    stdscr.erase()
    draw_window_border_lines()
    draw_window_border_corners()
    draw_window_titles()
    draw_window_contents()
    stdscr.refresh()


def read_worldstate():
    if not os.access(io["path_worldstate"], os.F_OK):
        msg = "No world state file found at " + io["path_worldstate"] + "."
        raise SystemExit(msg)
    read_anew = False
    worldstate_file = open(io["path_worldstate"], "r")
    turn_string = worldstate_file.readline()
    if int(turn_string) != world_data["turn"]:
        read_anew = True
    if not read_anew: # In rare cases, world may change, but not turn number.
        mtime = os.stat(io["path_worldstate"])
        if mtime != read_worldstate.last_checked_mtime:
            read_worldstate.last_checked_mtime = mtime
            read_anew = True
    if read_anew:
        cursed_main.redraw = True
        world_data["turn"] = int(turn_string)
        world_data["lifepoints"] = int(worldstate_file.readline())
        world_data["satiation"] = int(worldstate_file.readline())
        world_data["inventory"] = []
        while True:
            line = worldstate_file.readline().replace("\n", "")
            if line == '%':
                break
            world_data["inventory"] += [line]
        world_data["avatar_position"][0] = int(worldstate_file.readline())
        world_data["avatar_position"][1] = int(worldstate_file.readline())
        if not world_data["look_mode"]:
            world_data["map_center"][0] = world_data["avatar_position"][0]
            world_data["map_center"][1] = world_data["avatar_position"][1]
        world_data["map_size"] = int(worldstate_file.readline())
        world_data["fov_map"] = ""
        for i in range(world_data["map_size"]):
            line = worldstate_file.readline().replace("\n", "")
            world_data["fov_map"] += line
        world_data["mem_map"] = ""
        for i in range(world_data["map_size"]):
            line = worldstate_file.readline().replace("\n", "")
            world_data["mem_map"] += line
    worldstate_file.close()
read_worldstate.last_checked_mtime = -1


def read_message_queue():
    while (len(message_queue["messages"]) > 1
        or (len(message_queue["messages"]) == 1
            and not message_queue["open_end"])):
        message = message_queue["messages"].pop(0)
        if message == "THINGS_HERE START":
            read_message_queue.parse_thingshere = True
            world_data["look"] = []
        elif message == "THINGS_HERE END":
            read_message_queue.parse_thingshere = False
            if world_data["look"] == []:
                world_data["look"] = ["(none known)"]
            cursed_main.redraw = True
        elif read_message_queue.parse_thingshere:
            world_data["look"] += [message]
        elif message[0:4] == "LOG ":
            world_data["log"] += [message[4:]]
            cursed_main.redraw = True
        elif message == "WORLD_UPDATED":
            query_mapcell()
read_message_queue.parse_thingshere = False


def query_mapcell():
   command_sender("THINGS_HERE " + str(world_data["map_center"][0]) + " "
        + str(world_data["map_center"][1]))()
   world_data["look"] = ["(polling)"]


def cursed_main(stdscr):

    def ping_test():
        half_wait_time = 5
        if len(new_data_from_server) > 0:
            ping_test.sent = False
        elif ping_test.wait_start + half_wait_time < time.time():
            if not ping_test.sent:
                io["file_out"].write("PING\n")
                io["file_out"].flush()
                ping_test.sent = True
                ping_test.wait_start = time.time()
            elif ping_test.sent:
                raise SystemExit("Server not answering anymore.")
    ping_test.wait_start = 0

    def read_into_message_queue():
        if new_data_from_server == "":
            return
        new_open_end = False
        if new_data_from_server[-1] is not "\n":
            new_open_end = True
        new_messages = new_data_from_server.splitlines()
        if message_queue["open_end"]:
            message_queue["messages"][-1] += new_messages[0]
            del new_messages[0]
        message_queue["messages"] += new_messages
        if new_open_end:
            message_queue["open_end"] = True

    curses.noecho()
    curses.curs_set(False)
    signal.signal(signal.SIGWINCH,
        lambda ignore_1, ignore_2: set_window_geometries())
    set_window_geometries()
    delay = 1
    while True:
        stdscr.timeout(int(delay))
        delay = delay * 1.1 if delay < 1000 else delay
        if cursed_main.redraw:
            delay = 1
            draw_screen()
            cursed_main.redraw = False
        char = stdscr.getch()
        if char >= 0:
            char = chr(char)
            if char in commands:
                if len(commands[char]) == 1 or not world_data["look_mode"]:
                    commands[char][0]()
                    cursed_main.redraw = True
                else:
                    commands[char][1]()
                    cursed_main.redraw = True
        new_data_from_server = io["file_in"].read()
        ping_test()
        read_into_message_queue()
        read_worldstate()
        read_message_queue()


def win_map():
    win_size = next(win["size"] for win in windows if win["func"] == win_map)
    offset = [0, 0]
    for i in range(2):
        if world_data["map_center"][i] * (i + 1) > win_size[i] / 2 and \
                win_size[i] < world_data["map_size"] * (i + 1):
            if world_data["map_center"][i] * (i + 1) \
                < world_data["map_size"] * (i + 1) - win_size[i] / 2:
                offset[i] = world_data["map_center"][i] * (i + 1) \
                    - int(win_size[i] / 2)
                if i == 1:
                    offset[1] = offset[1] + world_data["map_center"][0] % 2
            else:
                offset[i] = world_data["map_size"] * (i + 1) - win_size[i] + i
    winmap_size = [world_data["map_size"], world_data["map_size"] * 2 + 1]
    winmap = []
    curses.init_pair(1, curses.COLOR_WHITE, curses.COLOR_BLUE)
    curses.init_pair(2, curses.COLOR_BLUE, curses.COLOR_BLACK)
    for y in range(world_data["map_size"]):
        for x in range(world_data["map_size"]):
            char = world_data["fov_map"][y * world_data["map_size"] + x]
            if world_data["look_mode"] and y == world_data["map_center"][0] \
                    and x == world_data["map_center"][1]:
                if char == " ":
                    char = \
                        world_data["mem_map"][y * world_data["map_size"] + x]
                winmap += [(char, curses.A_REVERSE), (" ", curses.A_REVERSE)]
                continue
            if char == " ":
                char = world_data["mem_map"][y * world_data["map_size"] + x]
                attribute = curses.color_pair(1) if char == " " \
                    else curses.color_pair(2)
                winmap += [(char, attribute), (" ", attribute)]
            else:
                winmap += char + " "
        if y % 2 == 0:
            winmap += "  "
    return offset, winmap_size, winmap


def win_inventory():
    win_size = next(win["size"] for win in windows
                                if win["func"] == win_inventory)
    winmap = []
    winmap_size = [0, win_size[1]]
    for line in world_data["inventory"]:
        winmap_size[1] = winmap_size[1] if len(line) <= winmap_size[1] \
            else len(line)
    count = 0
    for line in world_data["inventory"]:
        padding_size = winmap_size[1] - len(line)
        line += (" " * padding_size)
        if count == world_data["inventory_selection"]:
            line_new = []
            for x in range(len(line)):
                line_new += [(line[x], curses.A_REVERSE)]
            line = line_new
        winmap += line
        winmap_size[0] = winmap_size[0] + 1
        count += 1
    offset = [0, 0]
    if world_data["inventory_selection"] > win_size[0]/2:
        if world_data["inventory_selection"] < len(world_data["inventory"]) \
            - win_size[0]/2:
            offset[0] = world_data["inventory_selection"] - int(win_size[0]/2)
        else:
            offset[0] = len(world_data["inventory"]) - win_size[0]
    return offset, winmap_size, winmap


def win_look():
    winmap = ""
    winmap_size = [0, 0]
    for line in world_data["look"]:
        winmap_size[1] = winmap_size[1] if len(line) <= winmap_size[1] \
            else len(line)
    for line in world_data["look"]:
        padding_size = winmap_size[1] - len(line)
        winmap += line + (" " * padding_size)
        winmap_size[0] = winmap_size[0] + 1
    offset = [world_data["look_scroll"], 0]
    return offset, winmap_size, winmap


def win_info():
    winmap = "T: " + str(world_data["turn"]) \
        + " H: " + str(world_data["lifepoints"]) \
        + " S: " + str(world_data["satiation"])
    winmap_size = [1, len(winmap)]
    offset = [0, 0]
    return offset, winmap_size, winmap


def win_log():
    win_size = next(win["size"] for win in windows if win["func"] == win_log)
    offset = [0, 0]
    winmap = ""
    number_of_lines = 0
    for line in world_data["log"]:
        number_of_lines += math.ceil(len(line) / win_size[1])
        padding_size = win_size[1] - (len(line) % win_size[1])
        winmap += line + (padding_size * " ")
    if number_of_lines < win_size[0]:
        winmap = (" " * win_size[1] * (win_size[0] - number_of_lines)) + winmap
        number_of_lines = win_size[0]
    elif number_of_lines > win_size[0]:
        offset[0] = number_of_lines - win_size[0]
    winmap_size = [number_of_lines, win_size[1]]
    return offset, winmap_size, winmap


def command_quit():
    command_sender("QUIT")()
    raise SystemExit("Received QUIT command, forwarded to server, leaving.")


def command_toggle_look_mode():
    if not world_data["look_mode"]:
        world_data["look_mode"] = True
    else:
        world_data["look_mode"] = False
        world_data["map_center"] = world_data["avatar_position"]
        query_mapcell()


def command_sender(string, int_field=None):
    def command_send():
        int_string = ""
        if int_field:
            int_string = " " + str(world_data[int_field])
        io["file_out"].write(string + int_string + "\n")
        io["file_out"].flush()
    return command_send


def command_looker(string):
    def command_look():
        if string == "west" \
                and world_data["map_center"][1] > 0:
            world_data["map_center"][1] -= 1
        elif string == "east" \
                and world_data["map_center"][1] < world_data["map_size"] - 1:
            world_data["map_center"][1] += 1
        else:
            y_unevenness = world_data["map_center"][0] % 2
            y_evenness = int(not(y_unevenness))
            if string[6:] == "west" and \
                    world_data["map_center"][1] > -y_unevenness:
                if string[:5] == "north" and world_data["map_center"][0] > 0:
                    world_data["map_center"][0] -= 1
                    world_data["map_center"][1] -= y_evenness
                if string[:5] == "south" and world_data["map_center"][0] \
                        < world_data["map_size"] - 1:
                    world_data["map_center"][0] += 1
                    world_data["map_center"][1] -= y_evenness
            elif string[6:] == "east" and world_data["map_center"][1] \
                    < world_data["map_size"] - y_unevenness:
                if string[:5] == "north" and world_data["map_center"][0] > 0:
                    world_data["map_center"][0] -= 1
                    world_data["map_center"][1] += y_unevenness
                if string[:5] == "south" and world_data["map_center"][0] \
                        < world_data["map_size"] - 1:
                    world_data["map_center"][0] += 1
                    world_data["map_center"][1] += y_unevenness
        query_mapcell()
    return command_look


def command_look_scroller(string):
    def command_look_scroll():
        win_size = next(win["size"] for win in windows
                                    if win["func"] == win_look)
        if string == "up" and world_data["look_scroll"] > 0:
            world_data["look_scroll"] -= 1
        elif string == "down" and world_data["look_scroll"] \
                < len(world_data["look"]) - win_size[0]:
            world_data["look_scroll"] += 1
    return command_look_scroll


def command_inventory_selector(string):
    def command_inventory_select():
        if string == "up" and world_data["inventory_selection"] > 0:
            world_data["inventory_selection"] -= 1
        elif string == "down" and world_data["inventory_selection"] \
                < len(world_data["inventory"]) - 1:
            world_data["inventory_selection"] += 1
    return command_inventory_select


windows = [
    {"config": [1, 33], "func": win_info, "title": "Info"},
    {"config": [-7, 33], "func": win_log, "title": "Log"},
    {"config": [4, 16], "func": win_inventory, "title": "Inventory"},
    {"config": [4, 16], "func": win_look, "title": "Things here"},
    {"config": [0, -34], "func": win_map, "title": "Map"}
]
io = {
    "path_out": "server/in",
    "path_in": "server/out",
    "path_worldstate": "server/worldstate"
}
commands = {
    "A": (command_sender("ai"),),
    "D": (command_sender("drop", "inventory_selection"),),
    "J": (command_look_scroller("down"),),
    "K": (command_look_scroller("up"),),
    "P": (command_sender("pick_up"),),
    "Q": (command_quit,),
    "U": (command_sender("use", "inventory_selection"),),
    "W": (command_sender("wait"),),
    "c": (command_sender("move south-east"), command_looker("south-east")),
    "d": (command_sender("move east"), command_looker("east")),
    "e": (command_sender("move north-east"), command_looker("north-east")),
    "j": (command_inventory_selector("down"),),
    "k": (command_inventory_selector("up"),),
    "l": (command_toggle_look_mode,),
    "s": (command_sender("move west"), command_looker("west")),
    "w": (command_sender("move north-west"), command_looker("north-west")),
    "x": (command_sender("move south-west"), command_looker("south-west")),
}
message_queue = {
    "open_end": False,
    "messages": []
}
world_data = {
    "avatar_position": [-1, -1],
    "fov_map": "",
    "inventory": [],
    "inventory_selection": 0,
    "lifepoints": -1,
    "look": [],
    "look_mode": False,
    "look_scroll": 0,
    "log": [
"QUICK COMMAND OVERVIEW: "
"Move through map with 'w', 'e', 's', 'd', 'x', 'c'. "
"Pick up things with 'P', drop a thing selected from the inventory with 'D' "
"or use it with 'P'. "
"Move through inventory selection with 'j' and 'k'. "
"Toggle looking around mode with 'l'. "
"Scroll 'Things here' window with 'J' and 'K'. "
"Let AI decide next move with 'A'. "
"Quit with 'Q'. ",
"STATS OVERVIEW: "
"'T': Turn; 'H': Health (the higher, the better); "
"'S': Satiation (the closer to zero, the better).",
"See README file for more help."
],
    "map_center": [-1, -1],
    "map_size": 0,
    "mem_map": "",
    "satiation": -1,
    "turn": -1
}
sep_size = 1  # Width of inter-window borders and title bars.
stdscr = None
screen_size = [0,0]


try:
    if (not os.access(io["path_out"], os.F_OK)):
        msg = "No server input file found at " + io["path_out"] + "."
        raise SystemExit(msg)
    io["file_out"] = open(io["path_out"], "a")
    io["file_in"] = open(io["path_in"], "r")
    curses.wrapper(cursed_main)
except SystemExit as exit:
    print("ABORTING: " + exit.args[0])
except:
    print("SOMETHING WENT WRONG IN UNEXPECTED WAYS")
    raise
finally:
    if "file_out" in io:
        io["file_out"].close()
    if "file_in" in io:
        io["file_in"].close()