"""PlaigLab web app: upload a paper -> live forensic analysis against world
literature -> similarity + AI report. Run:  python webapp/server.py
"""
import os
import sys
import threading
import traceback
import uuid

from fastapi import FastAPI, File, HTTPException, UploadFile
from fastapi.responses import JSONResponse, Response
from fastapi.staticfiles import StaticFiles

ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
sys.path.insert(0, ROOT)
from plagdetect import store  # noqa: E402
from plagdetect.webpipeline import analyze_document  # noqa: E402

UPLOAD_DIR = os.path.join(ROOT, "data", "uploads")
STATIC_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)), "static")
ALLOWED = (".pdf", ".txt", ".docx")

app = FastAPI(title="PlaigLab")
JOBS = {}


def _run_job(job_id, path, depth):
    job = JOBS[job_id]

    def prog(msg):
        job["log"].append(msg)

    try:
        job["status"] = "running"
        job["result"] = analyze_document(path, progress=prog, depth=depth)
        job["status"] = "done"
        try:
            store.save_case(job["result"])      # persist for case history
        except Exception:
            traceback.print_exc()
    except Exception as exc:  # surfaced to the UI
        traceback.print_exc()
        job["status"] = "error"
        job["error"] = str(exc)


def _start(path, filename, depth="deep"):
    job_id = uuid.uuid4().hex[:12]
    JOBS[job_id] = {"status": "queued", "log": [], "result": None,
                    "error": None, "filename": filename}
    threading.Thread(target=_run_job, args=(job_id, path, depth),
                     daemon=True).start()
    return job_id


@app.post("/api/analyze")
async def analyze(file: UploadFile = File(...), depth: str = "deep"):
    ext = os.path.splitext(file.filename or "")[1].lower()
    if ext not in ALLOWED:
        raise HTTPException(400, f"Only {', '.join(ALLOWED)} files are supported")
    os.makedirs(UPLOAD_DIR, exist_ok=True)
    job_id = uuid.uuid4().hex[:6]
    dest = os.path.join(UPLOAD_DIR, f"{job_id}_{os.path.basename(file.filename)}")
    with open(dest, "wb") as f:
        f.write(await file.read())
    return {"job_id": _start(dest, file.filename, depth)}


@app.post("/api/sample")
def sample(depth: str = "deep"):
    path = os.path.join(ROOT, "data", "test_real.txt")
    if not os.path.exists(path):
        raise HTTPException(404, "sample document missing")
    return {"job_id": _start(path, "sample_paper.txt", depth)}


@app.get("/api/jobs/{job_id}")
def job_status(job_id: str):
    job = JOBS.get(job_id)
    if not job:
        raise HTTPException(404, "unknown job")
    return {"status": job["status"], "log": job["log"],
            "error": job["error"], "filename": job["filename"]}


@app.get("/api/jobs/{job_id}/report")
def job_report(job_id: str):
    job = JOBS.get(job_id)
    if not job or job["status"] != "done":
        raise HTTPException(404, "report not ready")
    return JSONResponse(job["result"])


@app.get("/api/jobs/{job_id}/manifest")
def job_manifest(job_id: str):
    """Downloadable coverage manifest (R2 — 'kya kya scrape kiya' full list)."""
    job = JOBS.get(job_id)
    if not job or job["status"] != "done":
        raise HTTPException(404, "manifest not ready")
    r = job["result"]
    payload = {"case_id": r["case_id"], "filename": r["filename"],
               "title": r["title"], "verdict": r["verdict"],
               "similarity_index": r["similarity_index"],
               "ai_score": r["ai_score"], "coverage": r["coverage"]}
    return JSONResponse(payload, headers={
        "Content-Disposition":
            f'attachment; filename="manifest_{r["case_id"]}.json"'})


def _result_for(job_id):
    job = JOBS.get(job_id)
    if job and job["status"] == "done":
        return job["result"]
    return store.get_case(job_id)        # fall back to persisted history


@app.get("/api/jobs/{job_id}/pdf")
def job_pdf(job_id: str):
    """Downloadable forensic PDF report."""
    r = _result_for(job_id)
    if not r:
        raise HTTPException(404, "report not ready")
    from plagdetect.pdfreport import build_pdf
    pdf = build_pdf(r)
    return Response(pdf, media_type="application/pdf", headers={
        "Content-Disposition":
            f'attachment; filename="plaiglab_{r.get("case_id", job_id)}.pdf"'})


@app.get("/api/cases")
def list_cases():
    """Past-case history (persisted across restarts)."""
    return {"cases": store.list_cases()}


@app.get("/api/cases/{case_id}")
def get_case(case_id: str):
    r = store.get_case(case_id)
    if not r:
        raise HTTPException(404, "unknown case")
    return JSONResponse(r)


app.mount("/", StaticFiles(directory=STATIC_DIR, html=True), name="static")

if __name__ == "__main__":
    import uvicorn
    # Host/port are env-driven so the same entrypoint works locally and on
    # container hosts (Hugging Face Spaces routes to 0.0.0.0:7860).
    host = os.environ.get("HOST", "127.0.0.1")
    port = int(os.environ.get("PORT", "8230"))
    uvicorn.run(app, host=host, port=port)