#!/usr/bin/env python3

from glob import glob
from pathlib import Path
import os
import itertools
import hashlib
import subprocess
import sys
from datetime import datetime
from string import StringFileConverter
from tm_tutor import TMDataBuilder, TutorDataBuilder

if sys.platform.startswith('win'):
    PathVar = os.environ.get('Path')
    Paths = PathVar.split(';')
    PATH = ''
    for candidatePath in Paths:
        if 'devkitARM' in candidatePath:
            PATH = candidatePath
            break
    if PATH == '':
        print('DevKit does not exist in your Path variable.\nChecking default location.')
        PATH = 'C://devkitPro//devkitARM//bin'
        if os.path.isdir(PATH) is False:
            print('...\nDevkit not found.')
            sys.exit(1)
        else:
            print('Devkit found.')

    PREFIX = '/arm-none-eabi-'
    AS = PATH + PREFIX + 'as'
    CC = PATH + PREFIX + 'gcc'
    LD = PATH + PREFIX + 'ld'
    GR = 'deps/grit.exe'
    WAV2AGB = 'deps/wav2agb.exe'
    MID2AGB = 'deps/mid2agb.exe'
    OBJCOPY = PATH + PREFIX + 'objcopy'

else:  # Linux, OSX, etc.
    PREFIX = 'arm-none-eabi-'
    AS = PREFIX + 'as'
    CC = PREFIX + 'gcc'
    LD = PREFIX + 'ld'
    GR = "grit"
    WAV2AGB = 'wav2agb'
    MID2AGB = 'mid2agb'
    OBJCOPY = PREFIX + 'objcopy'

SRC = './src'
GRAPHICS = './graphics'
ASSEMBLY = './assembly'
STRINGS = './strings'
AUDIO = './audio'
BUILD = './build'
IMAGES = './Images'
ASFLAGS = ['-mthumb', '-I', ASSEMBLY]
LDFLAGS = ['BPRE.ld', '-T', 'linker.ld']
CFLAGS = ['-mthumb', '-mno-thumb-interwork', '-mcpu=arm7tdmi', '-mtune=arm7tdmi',
          '-mno-long-calls', '-march=armv4t', '-Wall', '-Wextra', '-Os', '-fira-loop-pressure', '-fipa-pta']


class Master:
    @staticmethod
    def init():
        Master.printedCompilingImages = False
        Master.printedCompilingAudio = False
        Master.printedCompilingMusic = False

    @staticmethod
    def printCompilingImages():
        if not Master.printedCompilingImages:
            # Used to tell the script whether or not the string 'Compiling Images' has been printed
            Master.printedCompilingImages = True
            print('Compiling Images')

    @staticmethod
    def printCompilingAudio():
        if not Master.printedCompilingAudio:
            # Used to tell the script whether or not the string 'Compiling Audio' has been printed
            Master.printedCompilingAudio = True
            print('Compiling Audio')

    @staticmethod
    def printCompilingMusic():
        if not Master.printedCompilingMusic:
            # Used to tell the script whether or not the string 'Compiling Music' has been printed
            Master.printedCompilingMusic = True
            print('Compiling Music')


def RunCommand(cmd: [str]):
    """Runs the command line command."""
    try:
        subprocess.check_output(cmd)
    except subprocess.CalledProcessError as e:
        try:
            print(e.output.decode(), file=sys.stderr)
        except:
            print(e)
        sys.exit(1)


def CreateOutputFile(fileName: str, newFileName: str) -> [str, bool]:
    """Helper function to produce object file output."""
    if not os.path.isfile(fileName):
        return [newFileName, False]

    fileExists = os.path.isfile(newFileName)

    # If the object file was created after the file was last modified
    if fileExists and os.path.getmtime(newFileName) > os.path.getmtime(fileName):
        return [newFileName, False]

    return [newFileName, True]


def MakeGeneralOutputFile(fileName: str) -> [str, bool]:
    """Return hash of filename to use as object filename."""
    m = hashlib.md5()
    m.update(fileName.encode())
    newFileName = os.path.join(BUILD, m.hexdigest() + '.o')

    return CreateOutputFile(fileName, newFileName)


def MakeOutputImageFile(assemblyFile: str) -> [str, bool]:
    """Return 'IMG_' + hash of filename to use as object filename."""
    m = hashlib.md5()
    m.update(assemblyFile.encode())
    objectFile = os.path.join(BUILD, 'IMG_' + m.hexdigest() + '.o')

    return CreateOutputFile(assemblyFile, objectFile)


def MakeOutputAudioFile(assemblyFile: str) -> [str, bool]:
    """Return "SND_" + hash of filename to use as object filename."""
    objectFile = os.path.join(BUILD, 'SND_' + assemblyFile.split("gCry")[1].split(".s")[0] + '.o')
    return CreateOutputFile(assemblyFile, objectFile)


def MakeOutputMusicFile(assemblyFile: str) -> [str, bool]:
    """Return "MUS_" + hash of filename to use as object filename."""
    if sys.platform.startswith('win'):  # Windows
        objectFile = os.path.join(BUILD, 'MUS_'
                                  + assemblyFile.split('\\')[len(assemblyFile.split('\\')) - 1].split(".s")[0] + '.o')
    else:  # Linux, OSX, etc.
        objectFile = os.path.join(BUILD, 'MUS_'
                                  + assemblyFile.split('/')[len(assemblyFile.split('/')) - 1].split(".s")[0] + '.o')

    return CreateOutputFile(assemblyFile, objectFile)


def DoMiddleManAssembly(originalFile: str, assemblyFile: str, flagFile: str, flags: [str],
                        cmd: [str], func, printingFunc, isMusic: bool) -> str:
    """Process assembly files generated by things like grit, wav2agb, or mid2agb."""
    objectFile = func(assemblyFile)[0]
    fileExists = os.path.isfile(objectFile)
    flagFileExists = os.path.isfile(flagFile)

    if fileExists \
            and os.path.getmtime(objectFile) > os.path.getmtime(originalFile) \
            and (not flagFileExists or os.path.getmtime(objectFile) > os.path.getmtime(flagFile)):
        # If the .o file was created after the original and flag file were last modified
        return objectFile
    else:  # The original file or the flag file were modified recently
        printingFunc()
        RunCommand(cmd)

    if isMusic:  # Try to update the voicegroup manually
        counter = 0
        lineToChange = ''
        with open(assemblyFile, 'r') as file:
            for line in file:
                counter += 1
                if '_grp,' in line:
                    lineToChange = line.split('voicegroup')[0]
                    break

        if flags != [] and lineToChange != '' and '-G' in flags:
            ChangeFileLine(assemblyFile, counter, lineToChange + flags[flags.index('-G') + 1] + '\n')

    regenerateObjectFile = func(assemblyFile)[1]
    if regenerateObjectFile is False:
        os.remove(assemblyFile)
        return objectFile  # No point in recompiling file

    cmd = [AS] + ASFLAGS + ['-c', assemblyFile, '-o', objectFile]
    RunCommand(cmd)
    os.remove(assemblyFile)
    return objectFile


def ProcessAssembly(assemblyFile: str) -> str:
    """Assemble."""
    objectFile, regenerateObjectFile = MakeGeneralOutputFile(assemblyFile)
    if regenerateObjectFile is False:
        return objectFile  # No point in recompiling file

    try:
        print('Assembling %s' % assemblyFile)
        cmd = [AS] + ASFLAGS + ['-c', assemblyFile, '-o', objectFile]
        RunCommand(cmd)

    except FileNotFoundError:
        print('Error! The assembler could not be located.\n'
              + 'Are you sure you set up your path to devkitPro/devkitARM/bin correctly?')
        sys.exit(1)

    return objectFile


def ProcessC(cFile: str) -> str:
    """Compile C."""
    objectFile, regenerateObjectFile = MakeGeneralOutputFile(cFile)
    if regenerateObjectFile is False:
        return objectFile  # No point in recompiling file

    try:
        print('Compiling %s' % cFile)
        cmd = [CC] + CFLAGS + ['-c', cFile, '-o', objectFile]
        RunCommand(cmd)

    except FileNotFoundError:
        print('Error! The C compiler could not be located.\n'
              + 'Are you sure you set up your path to devkitPro/devkitARM/bin correctly?')
        sys.exit(1)

    return objectFile


def ProcessString(stringFile: str) -> str:
    """Build and assemble strings."""
    assemblyFile = stringFile.split('.string')[0] + '.s'
    objectFile = MakeGeneralOutputFile(assemblyFile)[0]
    fileExists = os.path.isfile(objectFile)

    if fileExists and os.path.getmtime(objectFile) > os.path.getmtime(stringFile):
        # If the .o file was created after the string file was last modified
        return objectFile

    print('Building Strings %s' % stringFile)
    StringFileConverter(stringFile)

    cmd = [AS] + ASFLAGS + ['-c', assemblyFile, '-o', objectFile]
    RunCommand(cmd)
    os.remove(assemblyFile)
    return objectFile


def GetFlagsFromFlagFile(filePath: str) -> [str]:
    try:
        with open(filePath, "r") as file:
            line = file.readline()  # Only needs the first line
            flags = line.split()
    except FileNotFoundError:
        print('"{}" could not be found.'.format(filePath))
        sys.exit(1)

    return flags


def ProcessSpriteSet(fileListing: [str], flags: [str], outputFile: str, title: str):
    assembledFile = os.path.join(ASSEMBLY, 'generated', outputFile)
    if (not os.path.isfile(assembledFile)
            or max(list(map(os.path.getmtime, fileListing))) > os.path.getmtime(assembledFile)):  # If a sprite has been modified
        print("Processing {}.".format(title))
        combinedFile = open(assembledFile, 'w')
        combinedFile.write('@THIS IS A GENERATED FILE! DO NOT MODIFY IT!\n')
        for sprite in fileListing:
            assembled = sprite.split('.png')[0] + '.s'

            if (not os.path.isfile(assembled)
                    or os.path.getmtime(sprite) > os.path.getmtime(assembled)):
                RunCommand([GR, sprite] + flags + ['-o', assembled])

            with open(assembled, 'r') as tempFile:
                combinedFile.write(tempFile.read())
        combinedFile.close()


def ProcessSpriteGraphics():
    frontFlags = GetFlagsFromFlagFile(GRAPHICS + "/frontspriteflags.grit")
    backFlags = GetFlagsFromFlagFile(GRAPHICS + "/backspriteflags.grit")
    iconFlags = GetFlagsFromFlagFile(GRAPHICS + "/iconspriteflags.grit")
    castformFlags = GetFlagsFromFlagFile(GRAPHICS + "/castform/gritflags.txt")

    backsprites = [file for file in glob(GRAPHICS + "/backspr" + "**/*.png", recursive=True)]
    frontsprites = [file for file in glob(GRAPHICS + "/frontspr" + "**/*.png", recursive=True)]
    iconsprites = [file for file in glob(GRAPHICS + "/pokeicon" + "**/*.png", recursive=True)]
    castformsprites = [file for file in glob(GRAPHICS + "/castform" + "**/*.png", recursive=True)]

    ProcessSpriteSet(frontsprites, frontFlags, 'frontsprites.s', "Front Sprites")
    ProcessSpriteSet(backsprites, backFlags, 'backsprites.s', "Back Sprites")
    ProcessSpriteSet(iconsprites, iconFlags, 'iconsprites.s', "Icon Sprites")
    ProcessSpriteSet(castformsprites, castformFlags, 'castformsprites.s', "Castform Sprites")


def ProcessAudio(audioFile: str) -> str:
    """Compile audio."""
    assemblyFile = audioFile.split('.wav')[0] + '.s'

    flags = []
    flagFile = audioFile.split('.wav')[0] + '_flags.txt'

    try:
        with open(flagFile, 'r') as file:
            line = file.readline()  # Only needs the first line
            flags = line.strip().split()
    except FileNotFoundError:
        pass

    cmd = [WAV2AGB, audioFile, assemblyFile] + flags

    return DoMiddleManAssembly(audioFile, assemblyFile, flagFile, flags, cmd,
                               MakeOutputAudioFile, Master.printCompilingAudio, False)


def ProcessMusic(midiFile: str) -> str:
    """Compile audio."""
    assemblyFile = midiFile.split('.mid')[0] + '.s'

    flags = []
    flagFile = midiFile.split('.mid')[0] + '_flags.txt'

    try:
        with open(flagFile, 'r') as file:
            line = file.readline()  # Only needs the first line
            flags = line.strip().split()
    except FileNotFoundError:
        pass

    cmd = [MID2AGB, midiFile, assemblyFile] + flags

    return DoMiddleManAssembly(midiFile, assemblyFile, flagFile, flags, cmd,
                               MakeOutputMusicFile, Master.printCompilingMusic, True)


def LinkObjects(objects: itertools.chain) -> str:
    """Link objects into one binary."""
    linked = 'build/linked.o'
    cmd = [LD] + LDFLAGS + ['-o', linked] + list(objects)
    RunCommand(cmd)
    return linked


def Objcopy(binary: str):
    """Run the objcopy."""
    cmd = [OBJCOPY, '-O', 'binary', binary, 'build/output.bin']
    RunCommand(cmd)


def RunGlob(globString: str, fn) -> map:
    """Glob recursively and run the processor function on each file in result."""
    if globString == '**/*.png' or globString == '**/*.bmp':  # Search the GRAPHICS location
        directory = GRAPHICS
    elif globString == '**/*.s':
        directory = ASSEMBLY
    elif globString == '**/*.string':
        directory = STRINGS
    elif globString == '**/*.wav' or globString == '**/*.mid':
        directory = AUDIO
    else:
        directory = SRC

    if sys.version_info > (3, 4):
        try:
            files = glob(os.path.join(directory, globString), recursive=True)
            return map(fn, files)

        except TypeError:
            print('Error compiling. Please make sure Python has been updated to the latest version.')
            sys.exit(1)
    else:
        files = Path(directory).glob(globString)
        return map(fn, map(str, files))


def main():
    Master.init()
    startTime = datetime.now()
    globs = {
        '**/*.s': ProcessAssembly,
        '**/*.c': ProcessC,
        '**/*.string': ProcessString,
        # '**/*.png': ProcessImage,
        # '**/*.bmp': ProcessImage,
        '**/*.wav': ProcessAudio,
        '**/*.mid': ProcessMusic,
    }

    if sys.version_info.major >= 3 and sys.version_info.minor >= 8:
        print("Warning! Python 3.8 may not be able to build this engine.\nPlease downgrade to Python 3.7.4")

    # Create output directory
    try:
        os.makedirs(BUILD)
    except FileExistsError:
        pass

    try:
        try:
            os.makedirs(ASSEMBLY + "/generated")
        except FileExistsError:
            pass

        ProcessSpriteGraphics()
        TMDataBuilder()
        TutorDataBuilder()

        # Gather source files and process them
        objects = itertools.starmap(RunGlob, globs.items())

        # Link and extract raw binary
        linked = LinkObjects(itertools.chain.from_iterable(objects))
        Objcopy(linked)

    except Exception as e:
        print("There was an error compiling the engine: {}".format(e))
        sys.exit(1)

    # Build special_inserts.asm
    if os.path.isfile('special_inserts.asm'):
        if not os.path.isfile('build/special_inserts.bin') \
                or os.path.getmtime('build/special_inserts.bin') < os.path.getmtime('special_inserts.asm'):
            print('Assembling special_inserts.asm')
            cmd = [AS] + ASFLAGS + ['-c', 'special_inserts.asm', '-o', 'build/special_inserts.o']
            RunCommand(cmd)

            cmd = [OBJCOPY, '-O', 'binary', 'build/special_inserts.o', 'build/special_inserts.bin']
            RunCommand(cmd)

    print('Built in ' + str(datetime.now() - startTime) + '.')


if __name__ == '__main__':
    main()