main.py

from fastapi import FastAPI, UploadFile, File, Request, Depends, HTTPException, APIRouter
from fastapi.responses import JSONResponse, FileResponse
from fastapi.middleware.cors import CORSMiddleware
from huggingface_hub import HfApi
from io import BytesIO
import re
import docx
from pathlib import Path
from docx.enum.text import WD_COLOR_INDEX
from PyPDF2 import PdfReader
from fastapi import FastAPI, UploadFile, File, Form
from fastapi.responses import JSONResponse
from Ai_rewriter.rewriter_fixed import rewrite_text
import uuid
import stripe
from pydantic import BaseModel
from supabase import create_client, Client
from dotenv import load_dotenv
import subprocess
import tempfile
import os
import shlex
load_dotenv()


# === CONFIG ===
HF_TOKEN = os.environ.get("HF_TOKEN")
HF_DATASET_REPO = "AlyanAkram/StealthReports"
CORS_ORIGINS = ["http://localhost:5173", "https://stealth-writer.vercel.app/"]

stripe.api_key = os.getenv("STRIPE_SECRET_KEY")
print("🔑 Stripe key loaded:", stripe.api_key, len(stripe.api_key))



supabase: Client | None = None
PRICE_MAP = {
    "basic":   "price_1RyxK4KiaPeHFPzzwBG5C5Rf",
    "premium": "price_1RyxKBKiaPeHFPzz5oDy6m2c",
}

# === FastAPI app setup ===
app = FastAPI(docs_url="/docs", redoc_url="/redoc", openapi_url="/openapi.json")

app.add_middleware(
    CORSMiddleware,
    allow_origins=CORS_ORIGINS,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# === Load model on startup ===
analyze_text = None
generate_pdf_report = None

@app.on_event("startup")
async def load_model():
    global analyze_text, generate_pdf_report, supabase
    from detector.custom_model import analyze_text as at, generate_pdf_report as gpr
    analyze_text = at
    generate_pdf_report = gpr

    supabase = create_client(
        os.getenv("SUPABASE_URL"),
        os.getenv("SUPABASE_KEY")
    )

# === Utils ===
def extract_text(file: UploadFile, ext: str) -> str:
    content = file.file.read()
    file_bytes = BytesIO(content)

    if ext == ".txt":
        return content.decode("utf-8", errors="ignore")
    elif ext == ".pdf":
        reader = PdfReader(file_bytes)
        return "".join([page.extract_text() or "" for page in reader.pages])
    elif ext == ".docx":
        doc = docx.Document(file_bytes)
        return "\n".join([para.text for para in doc.paragraphs])
    else:
        raise ValueError("Unsupported file type")

def sanitize_filename(name):
    return re.sub(r"[^\w\-_.]", "_", name)

def upload_to_dataset(path: str, content: BytesIO, token: str) -> str:
    api = HfApi()
    api.upload_file(
        path_or_fileobj=content,
        path_in_repo=path,
        repo_id=HF_DATASET_REPO,
        repo_type="dataset",
        token=token,
    )
    return f"https://huggingface.co/datasets/{HF_DATASET_REPO}/resolve/main/{path}"

# === Main endpoint ===
@app.post("/api/detect")
async def detect(file: UploadFile = File(...)):
    try:
        ext = os.path.splitext(file.filename)[1].lower()
        if ext not in [".txt", ".pdf", ".docx"]:
            raise ValueError("Unsupported file format")

        text = extract_text(file, ext)
        result = analyze_text(text)

        filename_base = sanitize_filename(os.path.splitext(file.filename)[0]) + "_" + str(uuid.uuid4())[:8]
        docx_buffer = BytesIO()
        doc = docx.Document()
        doc.add_heading("AI Detection Summary", level=1)
        doc.add_paragraph(f"Overall AI %: {result['overall_ai_percent']}%")
        doc.add_paragraph(f"Total Sentences: {result['total_sentences']}")
        doc.add_paragraph(f"AI Sentences: {result['ai_sentences']}")
        doc.add_paragraph("Sentences detected as AI are highlighted in cyan.\n")
        doc.add_heading("Sentence Analysis", level=2)

        paragraph = doc.add_paragraph()
        for para in result["results"]:
            for sentence, is_ai, _ in para:
                if not isinstance(sentence, str) or not sentence.strip():
                    continue
                run = paragraph.add_run(sentence + " ")
                if is_ai:
                    run.font.highlight_color = WD_COLOR_INDEX.TURQUOISE

        doc.save(docx_buffer)
        docx_buffer.seek(0)

        pdf_buffer = generate_pdf_report(result, filename_base)

        docx_url = upload_to_dataset(f"{filename_base}.docx", docx_buffer, HF_TOKEN)
        pdf_url = upload_to_dataset(f"{filename_base}.pdf", pdf_buffer, HF_TOKEN)

        return {
            "success": True,
            "score": {
                **{k: v for k, v in result.items() if k != "results"},
                "results": [
                    [{"sentence": s, "is_ai": is_ai, "ai_score": round(ai_score * 100, 2)} for s, is_ai, ai_score in para]
                    for para in result["results"]
                ]
            },
            "docx_url": docx_url,
            "pdf_url": pdf_url
        }

    except Exception as e:
        return JSONResponse(content={"success": False, "error": str(e)}, status_code=500)

router = APIRouter(prefix="/api/payments", tags=["payments"])

class CheckoutReq(BaseModel):
    plan: str
    success_url: str
    cancel_url: str
    email: str
    user_id: str

@router.post("/create-session")
async def create_session(data: CheckoutReq):
    if data.plan not in PRICE_MAP:
        raise HTTPException(400, "Unknown plan")

    session = stripe.checkout.Session.create(
        mode="subscription",
        payment_method_types=["card"],
        line_items=[{"price": PRICE_MAP[data.plan], "quantity": 1}],
        customer_email=data.email,
        client_reference_id=data.user_id,  # ✅ Store Supabase user.id
        success_url=data.success_url + "?session_id={CHECKOUT_SESSION_ID}",
        cancel_url=data.cancel_url,
    )
    return {"url": session.url}

@router.post("/webhook")
async def stripe_webhook(request: Request):
    payload = await request.body()
    sig_header = request.headers.get("stripe-signature")
    webhook_secret = os.getenv("STRIPE_WEBHOOK_SECRET")

    try:
        event = stripe.Webhook.construct_event(payload, sig_header, webhook_secret)
    except stripe.error.SignatureVerificationError:
        return JSONResponse(status_code=400, content={"error": "Invalid signature"})

    # ✅ First-time checkout completed
    if event["type"] == "checkout.session.completed":
        session = event["data"]["object"]
        user_id = session.get("client_reference_id")  # Supabase user.id
        subscription_id = session.get("subscription")

        try:
            subscription = stripe.Subscription.retrieve(subscription_id)
            price_id = subscription["items"]["data"][0]["price"]["id"]
            plan = next((k for k, v in PRICE_MAP.items() if v == price_id), None)

            if plan and user_id and supabase:
                print(f"Updating plan to {plan} for Supabase user {user_id}")
                response = supabase.rpc("update_user_plan", {
                    "uid": user_id,
                    "new_plan": plan
                }).execute()
                print("✅ Supabase update response:", response)

        except Exception as e:
            print("Webhook error while updating Supabase (checkout):", str(e))

    # ✅ Subscription renewals (monthly/annual billing)
    elif event["type"] == "invoice.payment_succeeded":
        invoice = event["data"]["object"]
        subscription_id = invoice.get("subscription")

        try:
            subscription = stripe.Subscription.retrieve(subscription_id)
            user_id = subscription.get("metadata", {}).get("user_id") \
                      or subscription.get("client_reference_id")
            price_id = subscription["items"]["data"][0]["price"]["id"]
            plan = next((k for k, v in PRICE_MAP.items() if v == price_id), None)

            if plan and user_id and supabase:
                print(f"Renewal: Updating plan to {plan} for Supabase user {user_id}")
                response = supabase.rpc("update_user_plan", {
                    "uid": user_id,
                    "new_plan": plan
                }).execute()
                print("✅ Supabase update response (renewal):", response)

        except Exception as e:
            print("Webhook error while updating Supabase (renewal):", str(e))

    # ✅ Subscription cancelled/expired
    elif event["type"] == "customer.subscription.deleted":
        subscription = event["data"]["object"]
        user_id = subscription.get("metadata", {}).get("user_id")

        try:
            if user_id and supabase:
                print(f"Downgrading Supabase user {user_id} to free plan")
                response = supabase.rpc("update_user_plan", {
                    "uid": user_id,
                    "new_plan": "free"
                }).execute()
                print("✅ Supabase update response (canceled):", response)

        except Exception as e:
            print("Webhook error while downgrading Supabase:", str(e))

    return {"status": "success"}


# Use environment variable if running on Hugging Face Spaces
output_dir_env = os.environ.get("REWRITTEN_OUTPUTS_DIR", "rewritten_outputs")
OUTPUT_DIR = Path(output_dir_env)
OUTPUT_DIR.mkdir(parents=True, exist_ok=True)

# Define the TextInput model
class TextInput(BaseModel):
    text: str

async def extract_text_from_file(file: UploadFile) -> str:
    """Wrapper to match your existing extract_text but works with async file read."""
    ext = os.path.splitext(file.filename)[1].lower()
    if ext not in [".txt", ".pdf", ".docx"]:
        raise ValueError("Unsupported file format")
    return extract_text(file, ext)


class RewriteRequest(BaseModel):
    text: str


@app.post("/rewrite")
async def rewrite_endpoint(file: UploadFile = File(...)):
    try:
        ext = os.path.splitext(file.filename)[1].lower()
        if ext not in [".txt", ".pdf", ".docx"]:
            raise ValueError("Unsupported file format")

        # 1. Save input file to temp
        temp_input = Path(tempfile.gettempdir()) / f"input_{uuid.uuid4().hex}{ext}"
        with open(temp_input, "wb") as f:
            f.write(await file.read())

        # 2. Temp output file
        temp_output = Path(tempfile.gettempdir()) / f"rewritten_{uuid.uuid4().hex}{ext}"

        # 3. Run rewriter_fixed.py on file
        subprocess.run(
            ["python", "-X", "utf8", "Ai_rewriter/rewriter_fixed.py", str(temp_input), str(temp_output)],
            check=True
        )

        if not temp_output.exists():
            raise HTTPException(status_code=500, detail="Rewriter did not produce an output file.")

        # 4. Create DOCX + PDF versions
        rewritten_text = ""
        if ext == ".txt":
            rewritten_text = temp_output.read_text(encoding="utf-8")
        elif ext == ".docx":
            import docx
            doc = docx.Document(temp_output)
            rewritten_text = "\n".join([p.text for p in doc.paragraphs])
        elif ext == ".pdf":
            from PyPDF2 import PdfReader
            reader = PdfReader(str(temp_output))
            rewritten_text = "".join([page.extract_text() or "" for page in reader.pages])

        # Create DOCX
        docx_buffer = BytesIO()
        doc = docx.Document()
        doc.add_paragraph(rewritten_text)
        doc.save(docx_buffer)
        docx_buffer.seek(0)

        # Create PDF
        from reportlab.lib.pagesizes import A4
        from reportlab.pdfgen import canvas
        from reportlab.lib.units import inch
        pdf_buffer = BytesIO()
        c = canvas.Canvas(pdf_buffer, pagesize=A4)
        width, height = A4
        text_object = c.beginText(0.5 * inch, height - 0.5 * inch)
        text_object.setFont("Times-Roman", 12)
        for line in rewritten_text.split("\n"):
            text_object.textLine(line)
        c.drawText(text_object)
        c.showPage()
        c.save()
        pdf_buffer.seek(0)

        # 5. Upload to Hugging Face dataset like detect
        filename_base = sanitize_filename(os.path.splitext(file.filename)[0]) + "_" + str(uuid.uuid4())[:8]
        docx_url = upload_to_dataset(f"{filename_base}.docx", docx_buffer, HF_TOKEN)
        pdf_url = upload_to_dataset(f"{filename_base}.pdf", pdf_buffer, HF_TOKEN)

        # 6. Cleanup
        temp_input.unlink(missing_ok=True)
        temp_output.unlink(missing_ok=True)

        return {
            "success": True,
            "docx_url": docx_url,
            "pdf_url": pdf_url
        }

    except subprocess.CalledProcessError as e:
        raise HTTPException(status_code=500, detail=f"Rewriter process failed: {e}")
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))



@app.post("/rewrite-text")
async def rewrite_text(req: RewriteRequest):
    temp_in_path = None
    temp_out_path = None
    try:
        # Always set file paths before subprocess to avoid reference errors
        temp_in = tempfile.NamedTemporaryFile(delete=False, suffix=".txt", mode="w", encoding="utf-8")
        temp_in.write(req.text)
        temp_in.close()
        temp_in_path = temp_in.name

        temp_out_path = Path(tempfile.gettempdir()) / f"rewritten_{os.path.basename(temp_in_path)}"

        # Prepare CLI exactly like your manual run, forcing UTF-8
        cmd = [
            "python", "-X", "utf8",
            "Ai_rewriter/rewriter_fixed.py",
            req.text,  # pass raw text directly
            str(temp_out_path)
        ]


        print("🚀 Running:", shlex.join(cmd))

        result = subprocess.run(
            cmd,
            capture_output=True,
            text=True,
            encoding="utf-8",
            errors="replace",
            shell=False
        )

        print("🔹 STDOUT:\n", result.stdout)
        print("🔹 STDERR:\n", result.stderr)

        if result.returncode != 0:
            raise HTTPException(
                status_code=500,
                detail=f"Model process failed: {result.stderr or 'Unknown error'}"
            )

        if not temp_out_path.exists():
            raise HTTPException(status_code=500, detail="Output file not found.")

        rewritten_text = temp_out_path.read_text(encoding="utf-8")

        return {"rewritten_text": rewritten_text}

    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))
    finally:
        # Cleanup safely
        if temp_in_path and os.path.exists(temp_in_path):
            os.remove(temp_in_path)
        if temp_out_path and os.path.exists(temp_out_path):
            os.remove(temp_out_path)



app.include_router(router)