import fxconv
import re
import os.path

def convert(input, output, params, target):
    if params["type"] == "map":
        convert_map(input, output, params, target)
    else:
        raise fxconv.FxconvError(f"unknown conversion {params['type']}")
        sys.exit(1)

def convert_map(input, output, params, target):
    TILE_AIR   = 0
    TILE_WALL  = 1
    TILE_START = 2
    TILE_END   = 3
    TILE_KEY   = 16
    TILE_VDOOR = 24
    TILE_HDOOR = 32

    # Read input file

    with open(input, "r") as fp:
        tiles, cycles = fp.read().split("\n\n")
        tiles = tiles.split("\n")
        cycle_texts = [c for c in cycles.split("\n") if c]

    w = max(len(t) for t in tiles)
    h = len(tiles)
    fog = 0

    filename = os.path.splitext(os.path.basename(input))[0]

    # Generate map contents

    encoded_tiles = bytearray(w * h)
    for (y, t) in enumerate(tiles):
        for (x, c) in enumerate(t):
            if c == " ":
                tile = TILE_AIR
            elif c == "#":
                tile = TILE_WALL
            elif c == "~":
                tile = TILE_START
            elif c == "@":
                tile = TILE_END
            elif ord("0") <= ord(c) <= ord("9"):
                tile = TILE_KEY + int(c)
            elif ord("a") <= ord(c) <= ord("z"):
                tile = TILE_VDOOR + (ord(c) - ord("a"))
            elif ord("A") <= ord(c) <= ord("Z"):
                tile = TILE_HDOOR + (ord(c) - ord("A"))
            else:
                raise fxconv.FxconvError(f"unknown tile character {c}")

            encoded_tiles[y*w + x] = tile

    # Parse door cycles

    RE_CYCLE = re.compile(r'^([a-zA-Z]):\s*([#.]+)$')
    cycles = dict()

    for c in cycle_texts:
        m = re.match(RE_CYCLE, c)
        if not m:
            raise fxconv.FxconvError(f"cannot parse door cycle '{c}'")
        cycles[m[1]] = m[2].encode("utf-8")

    # Generate door cycle data

    door_cycle = b""
    door_cycle_index = bytearray(16)

    for index, letter in enumerate("abcdefghABCDEFGH"):
        door_cycle_index[index] = len(door_cycle)
        if letter in cycles:
            door_cycle += cycles[letter] + b" "

    door_cycle = door_cycle + bytes(128 - len(door_cycle))

    # Generate the structure

    o = fxconv.ObjectData()
    o += fxconv.u32(w) + fxconv.u32(h) + fxconv.u32(fog)
    o += door_cycle + door_cycle_index
    o += fxconv.ref(f"img_{filename}")
    o += fxconv.ref(encoded_tiles)

    fxconv.elf(o, output, "_" + params["name"], **target)