import os
import sys
import shutil
import uuid
import zipfile

import gradio as gr

# Ensure repo root is importable on Spaces
ROOT = os.path.dirname(__file__)
if ROOT not in sys.path:
    sys.path.insert(0, ROOT)

import kmer_predict  # must be in repo root


PERSIST_BASE = "/tmp/kmer_predict_runs"
FASTA_EXTS = (".fa", ".fasta", ".fas", ".fna")


def _zip_dir(folder: str, zip_path: str) -> None:
    """Zip the contents of folder into zip_path."""
    with zipfile.ZipFile(zip_path, "w", zipfile.ZIP_DEFLATED) as z:
        for root, _, files in os.walk(folder):
            for fn in files:
                full = os.path.join(root, fn)
                rel = os.path.relpath(full, folder)
                z.write(full, rel)


def _safe_extract_zip(zip_path: str, dst_dir: str) -> None:
    """Safely extract only FASTA files from ZIP (prevents zip-slip)."""
    with zipfile.ZipFile(zip_path, "r") as z:
        for member in z.infolist():
            if member.is_dir():
                continue

            # Zip-slip protection
            target = os.path.normpath(os.path.join(dst_dir, member.filename))
            if not target.startswith(os.path.abspath(dst_dir) + os.sep):
                continue

            # Only FASTA-like files
            if not member.filename.lower().endswith(FASTA_EXTS):
                continue

            os.makedirs(os.path.dirname(target), exist_ok=True)
            with z.open(member) as src, open(target, "wb") as out:
                shutil.copyfileobj(src, out)


def _ingest_unknown_uploads(unknown_uploads, unknown_dir: str) -> None:
    """
    Accept unknown sequences as:
      - FASTA files, and/or
      - ZIP files containing FASTA files.
    Copies/extracts into unknown_dir.
    """
    os.makedirs(unknown_dir, exist_ok=True)

    if not unknown_uploads:
        return

    for idx, f in enumerate(unknown_uploads, start=1):
        src = getattr(f, "path", None) or getattr(f, "name", None) or str(f)
        orig = (
            getattr(f, "orig_name", None)
            or getattr(f, "filename", None)
            or os.path.basename(src)
        )
        lower = str(orig).lower()

        # ZIP → extract FASTA files
        if lower.endswith(".zip") or str(src).lower().endswith(".zip"):
            _safe_extract_zip(src, unknown_dir)
            continue

        # FASTA → copy
        if lower.endswith(FASTA_EXTS):
            dst_name = os.path.basename(orig)
        else:
            # If Gradio provides a temp name without extension, keep it readable
            dst_name = f"unknown_{idx}.fasta"

        shutil.copy(src, os.path.join(unknown_dir, dst_name))


def run_prediction(unknown_uploads, kmer_zip, seqtype, mode, identity, coverage, fdr):
    if not unknown_uploads:
        raise gr.Error("Please upload unknown FASTA files or a ZIP containing FASTA files.")
    if not kmer_zip:
        raise gr.Error("Please upload the k-mer results ZIP from Space 1.")

    os.makedirs(PERSIST_BASE, exist_ok=True)
    run_id = uuid.uuid4().hex[:10]
    run_dir = os.path.join(PERSIST_BASE, f"run_{run_id}")
    os.makedirs(run_dir, exist_ok=True)

    unknown_dir = os.path.join(run_dir, "unknown")
    outdir = os.path.join(run_dir, "predictions")
    os.makedirs(unknown_dir, exist_ok=True)
    os.makedirs(outdir, exist_ok=True)

    # Ingest unknown uploads (FASTA and/or ZIP)
    _ingest_unknown_uploads(unknown_uploads, unknown_dir)

    # Ensure we actually got sequences
    # (Lightweight check: presence of at least one fasta-like file)
    found_any = any(
        fn.lower().endswith(FASTA_EXTS)
        for _, _, files in os.walk(unknown_dir)
        for fn in files
    )
    if not found_any:
        raise gr.Error("No FASTA files were found after processing your uploads. Please check your ZIP contents.")

    # K-mer ZIP path (ZIP-only)
    kmer_zip_path = getattr(kmer_zip, "path", None) or getattr(kmer_zip, "name", None) or str(kmer_zip)
    if not str(kmer_zip_path).lower().endswith(".zip"):
        raise gr.Error("K-mer input must be a .zip file produced by Space 1.")

    # Run prediction
    kmer_predict.predict(
        unknown=unknown_dir,
        kmer_input=kmer_zip_path,
        output_dir=outdir,
        seqtype=seqtype,
        mode=mode,
        identity_threshold=float(identity),
        min_coverage=float(coverage),
        fdr_alpha=float(fdr),
        group_regex=kmer_predict.DEFAULT_GROUP_REGEX,
    )

    plot_path = os.path.join(outdir, "predicted_results_summary.png")
    csv_path = os.path.join(outdir, "predictions_by_alignment.csv")

    zip_path = os.path.join(run_dir, "prediction_outputs.zip")
    _zip_dir(outdir, zip_path)

    return plot_path, csv_path, zip_path


with gr.Blocks() as demo:
    gr.Markdown("# K-mer Sequence Predictor")
    gr.Markdown(
        "Upload **unknown sequences** (FASTA files or ZIP containing FASTA) and the **kmer_results.zip** from Space 1."
    )

    unknown_uploads = gr.File(
        label="Unknown sequences (FASTA files or ZIP containing FASTA)",
        file_count="multiple",
        file_types=[".fa", ".fasta", ".fas", ".fna", ".zip"],
    )

    kmer_zip = gr.File(
        label="kmer_results.zip (from Space 1)",
        file_count="single",
        file_types=[".zip"],
    )

    with gr.Row():
        seqtype = gr.Radio(["dna", "protein"], value="dna", label="Sequence type")
        mode = gr.Radio(["fast", "full"], value="fast", label="Mode")

    with gr.Row():
        identity = gr.Number(value=0.90, precision=2, label="Identity (full mode)")
        coverage = gr.Number(value=0.80, precision=2, label="Coverage (full mode)")
        fdr = gr.Number(value=0.05, precision=3, label="FDR alpha (full mode)")

    run_btn = gr.Button("Run prediction")

    out_plot = gr.Image(label="Prediction summary plot")
    out_csv = gr.File(label="Predictions CSV")
    out_zip = gr.File(label="Download all outputs (ZIP)")

    run_btn.click(
        fn=run_prediction,
        inputs=[unknown_uploads, kmer_zip, seqtype, mode, identity, coverage, fdr],
        outputs=[out_plot, out_csv, out_zip],
    )

if __name__ == "__main__":
    demo.launch()