from fasthtml.common import *
from PyPDF2 import PdfReader, PdfWriter, PdfMerger
import os, io, uuid, platform, subprocess

# 1. Setup 'static' folder (FastHTML auto-serves this directory)
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
UPLOAD_DIR = os.path.join(BASE_DIR, "pdf_outputs")

if not os.path.exists(UPLOAD_DIR):
    os.makedirs(UPLOAD_DIR)

# 2. FastHTML App Setup
app, rt = fast_app(
    hdrs=(
        Link(rel="stylesheet", href="https://cdn.jsdelivr.net/npm/@picocss/pico@2/css/pico.min.css"),
        Style("""
            :root { --pico-font-size: 90%; } /* Shrinks everything by 10% */
            h4 { margin-bottom: 0.5rem; font-size: 1.1rem; } /* Slims down card titles */
            .card { padding: 1rem; } /* Reduces internal card spacing */
            button { padding: 0.5rem 1rem; font-size: 0.9rem; } /* Slimmer buttons */
        """)
    ),
    live=False
)

@rt("/")
def get():
    return Titled("Modern PDF Toolbox",
        Container(
            P("Upload your PDFs and choose an operation."),
            Grid(
                Card(H4("Split PDF"),
                    Form(Input(type="file", name="file", accept=".pdf", required=True),
                         Button("Split into Pages", cls="secondary"),
                         hx_post="/split", hx_target="#result", enctype="multipart/form-data")),
                Card(H4("Merge PDFs"),
                    Form(Input(type="file", name="files", accept=".pdf", multiple=True, required=True),
                         Button("Merge Files"),
                         hx_post="/merge", hx_target="#result", enctype="multipart/form-data")),
            ),
            Grid(
                Card(H4("Rotate PDF"),
                    Form(Input(type="file", name="file", accept=".pdf", required=True),
                        Group(                     
                            Button("90° CW", name="angle", value="90", cls="outline"),
                            Button("180°", name="angle", value="180", cls="outline"),
                            Button("270° CW", name="angle", value="270", cls="outline"),
                        ),
                        hx_post="/rotate", hx_target="#result", enctype="multipart/form-data")),
                Card(H4("Extract Range"),
                    Form(Input(type="file", name="file", accept=".pdf", required=True),
                         Group(Input(type="number", name="start", placeholder="Start"),
                               Input(type="number", name="end", placeholder="End")),
                         Button("Extract", cls="secondary"),
                         hx_post="/extract", hx_target="#result", enctype="multipart/form-data")),
            ),
            Hr(),
            Section(id="result"), 
            Hr(),
            # --- Utility Section with the new button ---
            Div(
                Group(
                    Button("List Cached Files", hx_post="/open_folder", hx_target="#result", cls="outline"),
                    Button("Clear Cache", hx_post="/clear_cache", hx_target="#result", cls="contrast outline"),
                ),
                style="margin-top: 20px;"
            )
        )
    )

# --- UTILITY ROUTES ---

@rt("/open_folder")
def post():
    files = os.listdir(UPLOAD_DIR)
    if not files:
        return P("The cache is currently empty.", style="color: gray;")
    
    # Create a list of links for every file in the folder
    item_list = []
    for f in files:
        item_list.append(
            Li(
                A(f, href=f"/get-file/{f}", target="_blank"),
                style="font-size: 0.85rem;"
            )
        )
        
    return Div(
        H5("Files in Cache:"),
        Ul(*item_list),
        style="border: 1px solid #ccc; padding: 1rem; border-radius: 8px; margin-top: 1rem;"
    )

@rt("/clear_cache")
def post():
    files_deleted = 0
    for f in os.listdir(UPLOAD_DIR):
        file_path = os.path.join(UPLOAD_DIR, f)
        if os.path.isfile(file_path):
            os.remove(file_path)
            files_deleted += 1
    return Div(f"🧹 Cache cleared! {files_deleted} files removed.", cls="pico-color-green-500", style="font-weight: bold;")

# --- PDF OPERATION ROUTES ---

@rt("/split")
async def post(file: UploadFile):
    reader = PdfReader(io.BytesIO(await file.read()))
    sid = uuid.uuid4().hex[:6]
    links = []
    for i, page in enumerate(reader.pages):
        writer = PdfWriter()
        writer.add_page(page)
        fname = f"{sid}_p{i+1}.pdf"
        with open(os.path.join(UPLOAD_DIR, fname), "wb") as f:
            writer.write(f)
        links.append(Li(A(f"Download Page {i+1}", href=f"/pdf_outputs/{fname}", target="_blank")))
    return Div(H3(f"Split Complete ({len(reader.pages)} pages)"), Ul(*links))

@rt("/merge")
async def post(files: list[UploadFile]):
    merger = PdfMerger()
    for f in files: merger.append(io.BytesIO(await f.read()))
    fname = f"merged_{uuid.uuid4().hex[:6]}.pdf"
    with open(os.path.join(UPLOAD_DIR, fname), "wb") as f: merger.write(f)
    return Div(H3("Merge Complete!"), A("Download Combined PDF", href=f"/pdf_outputs/{fname}", role="button", target="_blank"))

@rt("/rotate")
async def post(file: UploadFile, angle: int):
    reader = PdfReader(io.BytesIO(await file.read()))
    writer = PdfWriter()
    for page in reader.pages:
        page.rotate(angle)
        writer.add_page(page)
    fname = f"rotated_{uuid.uuid4().hex[:6]}.pdf"
    with open(os.path.join(UPLOAD_DIR, fname), "wb") as f: writer.write(f)
    return Div(H3("Rotation Complete!"), A(f"View Rotated PDF", href=f"/pdf_outputs/{fname}", role="button", target="_blank"))

@rt("/extract")
async def post(file: UploadFile, start: int, end: int):
    reader = PdfReader(io.BytesIO(await file.read()))
    writer = PdfWriter()
    for i in range(max(0, start-1), min(end, len(reader.pages))): writer.add_page(reader.pages[i])
    fname = f"extract_{uuid.uuid4().hex[:6]}.pdf"
    with open(os.path.join(UPLOAD_DIR, fname), "wb") as f: writer.write(f)
    return Div(H3("Extraction Complete!"), A("Download Segment", href=f"/pdf_outputs/{fname}", role="button", target="_blank"))

if __name__ == "__main__":
    import uvicorn
    # The '0.0.0.0' tells the server to listen to the outside world
    uvicorn.run(app, host="0.0.0.0", port=int(os.getenv("PORT", 7860)))