from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import letter
from reportlab.lib.units import inch
from reportlab.pdfbase.pdfmetrics import stringWidth

OUT_PATH = r"C:\Users\jhodgkin\Pictures\Dearest Mother I Love You - Initials.pdf"

LINES = [
    "Gentle words I hear you say.",
    "Your kind hands help me each day.",
    "You're my mother kind and true;",
    "Dearest mother, I love you.",
]

W, H = letter
MARGIN = 0.5 * inch
FONT = "Helvetica-Bold"

def first_letters(line):
    return "  ".join(word[0].upper() for word in line.split())

def fit_font_size(c, text, max_width, start=200):
    size = start
    while size > 1:
        if stringWidth(text, FONT, size) <= max_width:
            return size
        size -= 1
    return size

def make_pdf():
    c = canvas.Canvas(OUT_PATH, pagesize=letter)

    initials = [first_letters(line) for line in LINES]
    max_w = W - 2 * MARGIN

    # Find a single font size that fits all lines
    size = min(fit_font_size(c, line, max_w) for line in initials)

    # Distribute lines evenly across the page height
    usable_h = H - 2 * MARGIN
    slot = usable_h / len(initials)

    for i, text in enumerate(initials):
        # Center vertically within each slot
        y = H - MARGIN - (i + 0.65) * slot
        c.setFont(FONT, size)
        c.drawCentredString(W / 2, y, text)

    c.save()
    print(f"Saved: {OUT_PATH}")
    print(f"Font size: {size}pt")
    for line, init in zip(LINES, initials):
        print(f"  {line!r} -> {init!r}")

make_pdf()