[WIP] Fix exif text overlap with color palette in border

[Copilot]

• Add max_width parameter to draw_exif in border.py to shrink fonts when text would overlap the palette
• Update main.py to calculate palette position/size before calling draw_exif, compute exif_max_width, and pass it to draw_exif
• Run validation

Original prompt

Problem

When using --border_type m (medium) with both --exif and --palette flags, the exif data text is drawn over the color palette instead of shrinking to fit the available space.

Root cause:

• draw_exif in border.py draws text horizontally (left-to-right) for non-centered border types (small, medium).
• The font size is only scaled to fit the height of the border, with no constraint on width.
• The color palette is placed in the bottom-right of the border, but draw_exif has no knowledge of how much horizontal space the palette occupies.
• As a result, the exif text can extend into and over the palette region.

Fix

1. border.py — Add max_width parameter to draw_exif

Add an optional max_width parameter to draw_exif. When provided (and the layout is non-centered), iteratively reduce the font sizes until all exif text lines fit within max_width.

def draw_exif(img: Image, exif: dict, border: Border, fontpath: str, boldfontpath: str, max_width: int = None) -> Image:
    centered = border.border_type in (BorderType.POLAROID, BorderType.LARGE, BorderType.INSTAGRAM)
    multiplier = 0.2 if centered else 0.5
    font_size = tm.get_optimal_font_size("Test string", border.bottom * multiplier, fontpath)
    heading_font_size = tm.get_optimal_font_size("Test string", border.bottom * (multiplier + 0.02), boldfontpath)

    # If a max_width is set (e.g. palette is present), shrink fonts until all exif lines fit
    if max_width and not centered:
        from PIL import ImageFont, ImageDraw
        exif_lines = [
            f"{exif['Make']} {exif['Model']}",
            f"{exif['LensMake']} {exif['LensModel']}",
            f"{exif['FocalLength']}  {exif['FNumber']}  {exif['ISOSpeedRatings']}  {exif['ExposureTime']}",
        ]
        while font_size > 1:
            test_heading = ImageFont.truetype(boldfontpath, heading_font_size)
            test_font = ImageFont.truetype(fontpath, font_size)
            dummy = ImageDraw.Draw(img)
            widths = [dummy.textlength(exif_lines[0], font=test_heading)] + \
                     [dummy.textlength(line, font=test_font) for line in exif_lines[1:]]
            if max(widths) <= max_width:
                break
            font_size -= 1
            heading_font_size = max(1, heading_font_size - 1)

    font = tm.create_font(font_size, fontpath)
    heading_font = tm.create_font(heading_font_size, boldfontpath)
    # ... rest of function unchanged

2. main.py — Calculate palette width before calling draw_exif, pass max_width

• Move the palette size and position calculation to before the exif drawing step.
• Compute exif_max_width = palette_x - border.left (the horizontal space available for text).
• Pass max_width=exif_max_width into draw_exif.
• Keep the actual overlay_palette call after exif drawing (order of image compositing unchanged).

exif_max_width = None

if add_palette:
    palette_size = round(border.bottom / 3)
    color_palette = load_image_color_palette(img, palette_size)
    palette_x = img_with_border.width - border.right - color_palette.width
    palette_y = img_with_border.height - round(border.bottom / 2) - round(color_palette.height / 2)
    exif_max_width = palette_x - border.left  # space available for exif text

if add_exif:
    exif = get_exif(img)
    if exif:
        ...
        img_with_border = draw_exif(img_with_border, exif, border, font_path, bold_font_path, max_width=exif_max_width)
        save_as = f'{save_as}_exif'

if add_palette:
    img_with_border = overlay_palette(img=img_with_border,
                                      color_palette=color_palette,
                                      offset=(palette_x, palette_y))
    save_as = f'{save_as}_palette'

Files to change

• border.py — draw_exif function
• main.py — process_image function

The following is the prior conversation context from the user's chat exploration (may be truncated):

User: when using the environment variable medium with exif data and color palette, sometimes the exif data prints over the color palette rather than shrinking further.

Assistant: Now I have a clear picture of the bug. Here's the root cause and fix:

---

Root Cause

When using --border_type m (medium) with both --exif and --palette:

1. draw_exif draws text horizontally (left-to-right) starting at x = border.left, because medium is not in the centered list (POLAROID, LARGE, INSTAGRAM). The font multiplier is 0.5 of border.bottom — larger than for centered layouts.
2. load_image_color_palette + overlay_palette then places a color palette in the bottom-right of the border.
3. The exif text is drawn before the palette and has no knowledge of how much horizontal space the palette will occupy — so it can extend into (and over) the palette region.

The exif drawing code in border.py (draw_exif) has no max_width constraint, and t...

This pull request was created from Copilot chat.