import os
import re
from datetime import datetime
from pathlib import Path

MIN_AGE = datetime.now().timestamp() - 12 * 60 * 60


def csv_cleanup(dirname: str = "misc/data"):
    if Path(dirname).is_file():
        csv_cleanup_file(Path(dirname))
    else:
        for csv_file in Path(dirname).glob("*.csv"):
            csv_cleanup_file(csv_file)


def csv_cleanup_file(csv_file: Path):
    temp_file = Path(str(csv_file) + ".tmp")
    error_file = Path(str(csv_file) + ".err")
    file_mtime = csv_file.stat().st_mtime
    if file_mtime < MIN_AGE:
        return
    print(csv_file.name)
    with open(csv_file, "r", encoding="latin-1", errors="ignore") as frh:
        with open(temp_file, "w", encoding="latin-1") as fwh:
            with open(error_file, "w", encoding="latin-1") as ewh:
                header = frh.readline()
                fwh.write(header)
                ewh.write(header)
                sep_count = header.count(";")

                buffer = ""
                buffer_count = 0
                solved_count = 0
                error_count = 0

                for line in frh.readlines():
                    line = line.replace("\t", "")
                    current_count = line.count(";")
                    if buffer_count + current_count == sep_count:
                        if buffer == "":
                            fwh.write(line)
                            continue
                        fwh.write(buffer + line)
                        print("*", end="")
                        solved_count += 1
                        buffer = ""
                        buffer_count = 0
                    elif buffer_count + current_count < sep_count:
                        buffer += re.subn(r"[\r\n]+", "", line)[0]
                        buffer_count = buffer.count(";")
                    else:
                        line2 = cleanup_line(buffer + line)
                        if line2.count(";") == sep_count:
                            fwh.write(line2)
                        else:
                            ewh.write(line2)
                            print("-", end="")
                            error_count += 1
                        buffer = ""
                        buffer_count = 0
                if error_count + solved_count > 0:
                    print("")

    os.utime(temp_file, (file_mtime, file_mtime))
    if solved_count > 0:
        print(f"Zeilenverschiebungen behoben: {solved_count}")

    if error_count == 0:
        error_file.unlink()
    else:
        print(f"!! Anzahl Fehler in '{csv_file.name}': {error_count} !!")
    csv_file.unlink()
    temp_file.rename(csv_file)


def cleanup_line(line):
    res = []
    buffer = ""

    line_iter = iter(line.strip("\r\n").split(";"))

    for col in line_iter:
        if '"' not in col:
            # no string
            res.append(col)
            continue

        buffer = col
        while buffer == '"' or buffer[-1] != '"':
            buffer += next(line_iter)
        res.append(buffer)

    return ";".join(res) + "\n"