"""

@relation(SDOC-SRS-157, scope=file)

"""

from typing import Optional

def get_color(ratio: float) -> str:

    """

    Returns a hex color string representing the coverage level.

    - 0% coverage → light red (#ffaaaa)

    - 50% coverage → yellow (#ffffaa)

    - 100% coverage → light green (#aaffaa)

    """

    assert isinstance(ratio, float) and 0 <= ratio <= 1

    lightness = 0xAA

    red = (0xFF, lightness, lightness)

    yellow = (0xFF, 0xFF, lightness)

    green = (lightness, 0xFF, lightness)

    if ratio < 0.5:

        # Interpolate between red and yellow.

        t = ratio / 0.5

        r = int(red[0] + (yellow[0] - red[0]) * t)

        g = int(red[1] + (yellow[1] - red[1]) * t)

        b = int(red[2] + (yellow[2] - red[2]) * t)

    else:

        # Interpolate between yellow and green.

        t = (ratio - 0.5) / 0.5

        r = int(yellow[0] + (green[0] - yellow[0]) * t)

        g = int(yellow[1] + (green[1] - yellow[1]) * t)

        b = int(yellow[2] + (green[2] - yellow[2]) * t)

    return f"#{r:02x}{g:02x}{b:02x}"

def split_into_max_n_lines(

    text: Optional[str], max_lines: int = 3, min_line_len: int = 42

) -> str:

    if not text:

        return ""

    total_len = len(text)

    ideal_len = total_len // max_lines

    lines = []

    start = 0

    n = len(text)

    for _ in range(max_lines - 1):

        # Stop splitting if the remaining text is short enough

        if n - start <= min_line_len:

            break

        end = start + ideal_len

        if end >= n:

            break

        # Move forward until the next space

        while end < n and text[end] != " ":

            end += 1

        # Append line and skip space

        lines.append(text[start:end].strip())

        start = end + 1  # skip space

    # Append the remaining text as the last line

    lines.append(text[start:].strip())

    return "<br>".join(lines)