import os
from pathlib import Path

# Presence of these means we should keep
EXCLUSIONS = {"LIBTBX", "FIXME", "DIALS", "pytest"}

EXCLUDE_FILES = {
    "conftest.py",
    "util/image_viewer/slip_viewer/frame.py",
    "util/installer.py",
}


def should_remove_line(filename, line):
    if any(x in str(filename) for x in EXCLUDE_FILES):
        return False
    if not line.strip():
        return True
    if line.startswith("#!") and (
        "command_line" in str(filename)
        or "setup.py" in str(filename)
        or "show_version.py" in str(filename)
    ):
        return False
    if "coding:" in line:
        return False
    if line.startswith("#") and any(x in line for x in EXCLUSIONS):
        return False
    if line.startswith("#"):
        return True


def filter_lines(filename, lines):
    lout = []
    line_pos = 0
    while lines and (not lines[line_pos].strip() or lines[line_pos].startswith("#")):
        #        if "coding" in lines[line_pos]:
        #            breakpoint()
        if not should_remove_line(filename, lines[line_pos]):
            if "coding" in lines[line_pos]:
                lout.append("# coding: utf-8\n")
            else:
                lout.append(lines[line_pos])
        line_pos += 1
    # If a block ended with newline, we might still have contents, so keep newline
    # Black will remove if was only file
    if line_pos > 0 and not lines[line_pos - 1].strip():
        lout.append(lines[line_pos - 1])
    lout.extend(lines[line_pos:])
    return lout


headers = []
for (path, dirs, files) in os.walk("."):
    for fname in files:
        if not fname.endswith(".py"):
            continue
        fullpath = Path(path) / fname
        lines = []
        with open(fullpath) as f:
            lines = f.readlines()

        lines_out = filter_lines(fullpath, lines)

        if not lines_out == lines:
            with open(fullpath, "w") as f:
                f.write("".join(lines_out))