from pathlib import Path
import re
import sys

errors = []


def find_all(a_str, sub):
    for i, line in enumerate(a_str.splitlines()):
        column = 0
        while True:
            column = line.find(sub, column)
            if column == -1:
                break
            yield i, column
            column += len(sub)


section_regex = re.compile(r'^(=+|-+|\*+|~+)$')
directive_regex = re.compile(r'^(\s*)\.\. (.*)::.*$')
directive_arg_regex = re.compile(r'^(\s+):.*:\s*.*$')
esphome_io_regex = re.compile(r'https://esphome.io/')


for f in sorted(Path('.').glob('**/*.rst')):
    try:
        content = f.read_text('utf-8')
    except UnicodeDecodeError:
        errors.append("File {} is not readable as UTF-8. Please set your editor to UTF-8 mode."
                      "".format(f))
        continue

    if not content.endswith('\n'):
        errors.append("Newline at end of file missing. Please insert an empty line at end "
                      "of file {}".format(f))

    # Check tab character
    for line, col in find_all(content, '\t'):
        errors.append("File {} contains tab character on line {}:{}. "
                      "Please convert tabs to spaces.".format(f, line + 1, col))
    # Check windows newline
    for line, col in find_all(content, '\r'):
        errors.append("File {} contains windows newline on line {}:{}. "
                      "Please set your editor to unix newline mode.".format(f, line + 1, col))

    lines = content.splitlines(keepends=False)

    for i, line in enumerate(lines):
        if i == 0:
            continue

        if not section_regex.match(line):
            continue
        line_above = lines[i - 1]
        if len(line_above) != len(line):
            errors.append("The title length must match the bar length below it. See {}:{}"
                          "".format(f, i+1))
        if i + 1 < len(lines) and lines[i + 1]:
            errors.append("Empty line after heading is missing. Please insert an "
                          "empty line. See {}:{}".format(f, i+1))

    for i, line in enumerate(lines):
        m = directive_regex.match(line)
        if m is None:
            continue
        base_indentation = len(m.group(1))
        directive_name = m.group(2)
        if directive_name.startswith('|') or directive_name == 'seo':
            continue
        # Match directive args
        for j in range(i + 1, len(lines)):
            if not directive_arg_regex.match(lines[j]):
                break
        else:
            # Reached end of file
            continue

        # Empty line must follow
        if lines[j]:
            errors.append("Directive '{}' is not followed by an empty line. Please insert an "
                          "empty line after {}:{}".format(directive_name, f, j))
            continue

        k = j + 1
        for j in range(k, len(lines)):
            if not lines[j]:
                # Ignore Empty lines
                continue

            num_spaces = len(lines[j]) - len(lines[j].lstrip())
            if num_spaces <= base_indentation:
                # Finished with this directive
                break
            num_indent = num_spaces - base_indentation
            if j == k and num_indent != 4:
                errors.append("Directive '{}' must be indented with 4 spaces, not {}. See "
                              "{}:{}".format(directive_name, num_indent, f, j+1))
                break

    for i, line in enumerate(lines):
        if esphome_io_regex.search(line):
            if 'privacy.rst' in str(f) or 'web_server.rst' in str(f):
                continue
            errors.append("All links to esphome.io should be relative, please remove esphome.io "
                          "from URL. See {}:{}".format(f, i+1))


for error in errors:
    print(error)

sys.exit(len(errors))