from csv import reader
from difflib import ndiff
from importlib import reload
from os import path

import scriptshifter.tables

from scriptshifter.trans import transliterate


TEST_DIR = path.dirname(path.realpath(__file__))
TEST_DATA_DIR = path.join(TEST_DIR, "data")


def reload_tables():
    reload(scriptshifter.tables)  # Reload new config dir.
    from scriptshifter import tables
    tables.list_tables.cache_clear()
    tables.load_table.cache_clear()

    return tables


def test_sample(dset):
    """
    Test an individual sample set and produce a human-readable report.

    Used outside of automated tests.

    @param dset (str): sample set name (without the .csv extension) found in
    the `data/script_samples` directory.
    """
    deltas = []
    dset_fpath = path.join(TEST_DATA_DIR, "script_samples", dset + ".csv")
    log_fpath = path.join(TEST_DATA_DIR, f"test_{dset}.log")

    with open(dset_fpath, newline="") as fh:
        csv = reader(fh)
        for row in csv:
            lang, script, rom = row[:3]
            opts = row[3] if len(row) > 3 and row[3] else {}
            trans, warnings = transliterate(script, lang, "s2r", opts)
            if (trans == rom):
                print(".", end="")
            else:
                print("F", end="")
                deltas.append((script, ndiff([trans], [rom])))

    with open(log_fpath, "w") as fh:
        # If no deltas, just truncate the file.
        for script, delta in deltas:
            fh.write(f"Original: {script}\n")
            for dline in delta:
                fh.write(dline.strip() + "\n")
            fh.write("\n\n")

    ct = len(deltas)
    if ct > 0:
        print(f"{ct} failed tests. See report at {log_fpath}")
    else:
        print("All tests passed.")