app.py

#!/usr/bin/env python3
"""Gradio web UI for pdfclean — drag-and-drop PDF watermark/footer removal."""
import os
import tempfile
import zipfile
import gradio as gr
from pdfclean import clean_pdf_headless, extract_title

# ─── Theme ───────────────────────────────────────────────────────────────────
# Dark charcoal + bone-white. Calm, soothing, confident.

CHARCOAL = "#141414"         # background — uniform dark
CHARCOAL_LIGHT = "#141414"   # cards, panels — same as bg (no two-tone)
CHARCOAL_MID = "#1E1E1E"     # inputs, elevated surfaces
CHARCOAL_SOFT = "#2A2A2A"    # borders, dividers
BONE = "#E4E4E4"             # primary text
BONE_DIM = "#8A8A8A"         # secondary text, labels
BONE_FAINT = "#5A5A5A"       # placeholders, muted
ACCENT = "#E4E4E4"           # white accent (buttons)
ACCENT_HOVER = "#FFFFFF"

theme = gr.themes.Base(
    primary_hue=gr.themes.Color(
        c50=ACCENT, c100=ACCENT, c200=ACCENT, c300=ACCENT,
        c400=ACCENT, c500=ACCENT, c600=ACCENT, c700=ACCENT,
        c800=ACCENT, c900=ACCENT, c950=ACCENT,
    ),
    neutral_hue=gr.themes.Color(
        c50=BONE, c100="#e8e4dc", c200="#d0ccc4", c300=BONE_DIM,
        c400=BONE_FAINT, c500="#5c5954", c600=CHARCOAL_SOFT,
        c700=CHARCOAL_MID, c800=CHARCOAL_LIGHT, c900=CHARCOAL,
        c950="#111111",
    ),
    font=[gr.themes.GoogleFont("Instrument Sans"), "Helvetica", "Arial", "sans-serif"],
    font_mono=[gr.themes.GoogleFont("JetBrains Mono"), "monospace"],
).set(
    # Body
    body_background_fill=CHARCOAL,
    body_background_fill_dark=CHARCOAL,
    body_text_color=BONE,
    body_text_color_dark=BONE,
    body_text_color_subdued=BONE_DIM,
    body_text_color_subdued_dark=BONE_DIM,

    # Blocks (panels, cards)
    block_background_fill=CHARCOAL_LIGHT,
    block_background_fill_dark=CHARCOAL_LIGHT,
    block_border_color=CHARCOAL_SOFT,
    block_border_color_dark=CHARCOAL_SOFT,
    block_label_text_color=BONE_DIM,
    block_label_text_color_dark=BONE_DIM,
    block_label_background_fill=CHARCOAL_MID,
    block_label_background_fill_dark=CHARCOAL_MID,
    block_title_text_color=BONE,
    block_title_text_color_dark=BONE,

    # Inputs
    input_background_fill=CHARCOAL_MID,
    input_background_fill_dark=CHARCOAL_MID,
    input_border_color=CHARCOAL_SOFT,
    input_border_color_dark=CHARCOAL_SOFT,
    input_border_color_focus=ACCENT,
    input_border_color_focus_dark=ACCENT,
    input_placeholder_color=BONE_FAINT,
    input_placeholder_color_dark=BONE_FAINT,

    # Buttons
    button_primary_background_fill=ACCENT,
    button_primary_background_fill_dark=ACCENT,
    button_primary_background_fill_hover=ACCENT_HOVER,
    button_primary_background_fill_hover_dark=ACCENT_HOVER,
    button_primary_text_color=CHARCOAL,
    button_primary_text_color_dark=CHARCOAL,
    button_secondary_background_fill=CHARCOAL_MID,
    button_secondary_background_fill_dark=CHARCOAL_MID,
    button_secondary_text_color=BONE,
    button_secondary_text_color_dark=BONE,
    button_secondary_border_color=CHARCOAL_SOFT,
    button_secondary_border_color_dark=CHARCOAL_SOFT,

    # Checkbox
    checkbox_background_color=CHARCOAL_MID,
    checkbox_background_color_dark=CHARCOAL_MID,
    checkbox_background_color_selected=ACCENT,
    checkbox_background_color_selected_dark=ACCENT,
    checkbox_border_color=CHARCOAL_SOFT,
    checkbox_border_color_dark=CHARCOAL_SOFT,
    checkbox_border_color_selected=ACCENT,
    checkbox_border_color_selected_dark=ACCENT,
    checkbox_label_text_color=BONE,
    checkbox_label_text_color_dark=BONE,

    # Panels
    panel_background_fill=CHARCOAL_LIGHT,
    panel_background_fill_dark=CHARCOAL_LIGHT,
    panel_border_color=CHARCOAL_SOFT,
    panel_border_color_dark=CHARCOAL_SOFT,

    # Borders
    border_color_primary=CHARCOAL_SOFT,
    border_color_primary_dark=CHARCOAL_SOFT,
    border_color_accent=ACCENT,
    border_color_accent_dark=ACCENT,

    # Loader
    loader_color=ACCENT,
    loader_color_dark=ACCENT,

    # Shadow
    button_primary_shadow="none",
    button_primary_shadow_dark="none",
    button_primary_shadow_hover="none",
    button_primary_shadow_hover_dark="none",
    button_primary_shadow_active="none",
    button_primary_shadow_active_dark="none",
)

CUSTOM_CSS = """
.gradio-container { max-width: 960px !important; margin: 0 auto !important; }
.prose h1 { color: #E4E4E4 !important; font-weight: 600 !important; letter-spacing: -0.02em; }
.prose h3 { color: #8A8A8A !important; font-weight: 500 !important; }
.prose p, .prose li { color: #8A8A8A !important; }
.prose strong { color: #E4E4E4 !important; }
.prose code { color: #E4E4E4 !important; background: #1E1E1E !important; }
footer { display: none !important; }
"""


# ─── Helpers ─────────────────────────────────────────────────────────────────

def make_zip(file_paths):
    """Bundle multiple files into a single ZIP for easy download."""
    tmp = tempfile.NamedTemporaryFile(suffix=".zip", delete=False)
    with zipfile.ZipFile(tmp.name, "w", zipfile.ZIP_DEFLATED) as zf:
        for path in file_paths:
            zf.write(path, os.path.basename(path))
    return tmp.name


# ─── Processing ──────────────────────────────────────────────────────────────

def process_pdfs(pdf_files, export_markdown):
    """Clean multiple PDFs and return results."""
    if not pdf_files:
        raise gr.Error("Please upload at least one PDF file.")

    output_files = []
    all_status = []

    for pdf_file in pdf_files:
        input_path = pdf_file if isinstance(pdf_file, str) else pdf_file.name
        basename = os.path.basename(input_path)

        # Generate output path
        title_slug = extract_title(input_path)
        tmp_dir = tempfile.mkdtemp()
        if title_slug:
            out_name = f"{title_slug}.pdf"
        else:
            out_name = os.path.splitext(basename)[0] + "-clean.pdf"
        output_path = os.path.join(tmp_dir, out_name)

        # Clean
        success, messages, md_path = clean_pdf_headless(
            input_path, output_path, export_md=export_markdown
        )

        output_files.append(output_path)
        if md_path:
            output_files.append(md_path)

        # Status
        icon = "✓" if success else "⚠"
        all_status.append(f"{icon}  {basename} → {out_name}\n   " + "\n   ".join(messages))

    # ZIP if multiple outputs
    if len(output_files) > 1:
        output_files.append(make_zip(output_files))

    status_text = "\n\n".join(all_status)
    return output_files, status_text


# ─── UI ──────────────────────────────────────────────────────────────────────

with gr.Blocks(title="pdfclean", theme=theme, css=CUSTOM_CSS) as app:

    gr.Markdown(
        "# pdfclean\n"
        "### Remove watermarks and footers from academic PDFs\n\n"
        "Upload one or more PDFs — watermarks like *\"Do Not Copy or Post\"* and "
        "repeating footer lines (authorization notices, phone numbers, copyright) "
        "are detected automatically and removed. "
        "You can also export to clean **Markdown**.\n\n"
        "**How it works:** Watermarks are detected by their rotation and size. "
        "Footers are detected by repetition — text at the same position on most pages. "
        "Body text, tables, footnotes, and page numbers are preserved."
    )

    with gr.Row():
        with gr.Column(scale=1):
            pdf_input = gr.File(
                label="Upload PDFs",
                file_types=[".pdf"],
                file_count="multiple",
            )
            md_toggle = gr.Checkbox(label="Export markdown", value=True)
            btn = gr.Button("Clean PDFs", variant="primary", size="lg")

        with gr.Column(scale=1):
            output_files = gr.File(label="Download results", file_count="multiple")
            status = gr.Textbox(label="Status", interactive=False, lines=6)

    btn.click(
        fn=process_pdfs,
        inputs=[pdf_input, md_toggle],
        outputs=[output_files, status],
    )

    # Example file (if present)
    if os.path.exists("example.pdf"):
        gr.Examples(
            examples=[["example.pdf"]],
            inputs=[pdf_input],
            label="Try an example",
        )

app.launch(
    auth=("user", "welovecollective"),
    auth_message="Username: user",
    ssr_mode=False,
)