# File: plugins/utility/routes.py

# Standard library
import csv
import io
import os
import re
import uuid
import zipfile
import tempfile
import difflib
import traceback
from datetime import datetime

# Third‐party
from flask import (
    Blueprint, request, render_template, redirect, flash,
    session, url_for, send_file, current_app
)
from flask_login import login_required, current_user
from flask_wtf.csrf import generate_csrf
from werkzeug.utils import secure_filename
from werkzeug.datastructures import FileStorage

# Application
from app import db
from app.neo4j_utils import get_neo4j_handler

# Plugins
from plugins.plant.models import (
    Plant,
    PlantCommonName,
    PlantScientificName,
    PlantOwnershipLog,
)
from plugins.media.models import Media
from plugins.utility.models import ImportBatch
from plugins.media.routes import _process_upload_file

bp = Blueprint(
    'utility',
    __name__,
    template_folder='templates',
    url_prefix='/utility'
)


@bp.route("/", methods=["GET"])
@login_required
def index():
    return redirect(url_for("utility.upload"))


@bp.route("/imports", methods=["GET"])
@login_required
def imports():
    batches = (
        ImportBatch.query
                   .filter_by(user_id=current_user.id)
                   .order_by(ImportBatch.imported_at.desc())
                   .limit(20)
                   .all()
    )
    return render_template("utility/imports.html", batches=batches)


# ────────────────────────────────────────────────────────────────────────────────
PLANT_HEADERS    = [
    "UUID","Type","Name","Scientific Name",
    "Vendor Name","Price","Mother UUID","Notes",
    "Short ID"
]
MEDIA_HEADERS    = [
    "Plant UUID","Image Path","Uploaded At","Source Type"
]
REQUIRED_HEADERS = {"uuid", "plant_type", "name", "scientific_name", "mother_uuid"}


@bp.route("/upload", methods=["GET", "POST"])
@login_required
def upload():
    # -------------------------------------------------------------------------
    # POST handling
    # -------------------------------------------------------------------------
    if request.method == "POST":
        file = request.files.get("file")
        if not file or not file.filename:
            flash("No file selected", "error")
            return redirect(request.url)

        filename = file.filename.lower().strip()

        # ── ZIP Import Flow ────────────────────────────────────────────────
        if filename.endswith(".zip"):
            # 1) Save to shared UPLOAD_FOLDER
            upload_dir = current_app.config["UPLOAD_FOLDER"]
            os.makedirs(upload_dir, exist_ok=True)
            tmp_path = os.path.join(upload_dir, f"tmp_{uuid.uuid4().hex}.zip")
            file.save(tmp_path)

            # 2) Validate ZIP + contents
            try:
                zf = zipfile.ZipFile(tmp_path)
            except zipfile.BadZipFile:
                os.remove(tmp_path)
                flash("Uploaded file is not a valid ZIP.", "danger")
                return redirect(request.url)

            names = set(zf.namelist())
            if not {"plants.csv", "media.csv"}.issubset(names):
                os.remove(tmp_path)
                flash("ZIP must contain both plants.csv and media.csv", "danger")
                return redirect(request.url)

            # 3) Extract export_id from metadata.txt
            export_id = None
            if "metadata.txt" in names:
                meta = zf.read("metadata.txt").decode("utf-8", "ignore")
                for line in meta.splitlines():
                    if line.startswith("export_id,"):
                        export_id = line.split(",", 1)[1].strip()
                        break
            if not export_id:
                os.remove(tmp_path)
                flash("metadata.txt missing or missing export_id", "danger")
                return redirect(request.url)

            # 4) Prevent duplicate imports
            if ImportBatch.query.filter_by(export_id=export_id, user_id=current_user.id).first():
                os.remove(tmp_path)
                flash("This export has already been imported.", "info")
                return redirect(request.url)

            # 5) Create batch record
            batch = ImportBatch(
                export_id   = export_id,
                user_id     = current_user.id,
                imported_at = datetime.utcnow(),
                status      = 'pending'
            )
            db.session.add(batch)
            db.session.commit()

            # 6) Rename ZIP to include batch.id
            final_path = os.path.join(upload_dir, f"{batch.id}_{uuid.uuid4().hex}.zip")
            os.rename(tmp_path, final_path)

            # 7) Enqueue Celery task
            from plugins.utility.tasks import import_text_data
            import_text_data.delay(final_path, "zip", batch.id)

            flash("ZIP received; import queued in background.", "success")
            return redirect(request.url)

        # ── CSV Review Flow ─────────────────────────────────────────────────
        if filename.endswith(".csv"):
            try:
                stream = io.StringIO(file.stream.read().decode("utf-8-sig"))
                reader = csv.DictReader(stream)
            except Exception:
                flash("Failed to read CSV file. Ensure it is valid UTF-8.", "error")
                return redirect(request.url)

            headers = set(reader.fieldnames or [])
            missing = REQUIRED_HEADERS - headers
            if missing:
                flash(f"Missing required CSV headers: {missing}", "error")
                return redirect(request.url)

            session["pending_rows"] = []
            review_list = []
            all_common  = {c.name.lower(): c for c in PlantCommonName.query.all()}
            all_sci     = {s.name.lower(): s for s in PlantScientificName.query.all()}

            for row in reader:
                uuid_val    = row.get("uuid", "").strip().strip('"')
                name        = row.get("name", "").strip()
                sci_name    = row.get("scientific_name", "").strip()
                plant_type  = row.get("plant_type", "").strip() or "plant"
                mother_uuid = row.get("mother_uuid", "").strip().strip('"')

                if not (uuid_val and name and plant_type):
                    continue

                suggestions = difflib.get_close_matches(
                    sci_name.lower(), list(all_sci.keys()),
                    n=1, cutoff=0.8
                )
                suggested = None
                if suggestions and suggestions[0] != sci_name.lower():
                    suggested = all_sci[suggestions[0]].name

                item = {
                    "uuid"        : uuid_val,
                    "name"        : name,
                    "sci_name"    : sci_name,
                    "suggested"   : suggested,
                    "plant_type"  : plant_type,
                    "mother_uuid" : mother_uuid
                }
                review_list.append(item)
                session["pending_rows"].append(item)

            session["review_list"] = review_list
            return redirect(url_for("utility.review"))

        # ── Direct Media Upload Flow ───────────────────────────────────────
        plugin     = request.form.get("plugin", "")
        related_id = request.form.get("related_id", 0)
        plant_id   = request.form.get("plant_id", None)
        growlog_id = request.form.get("growlog_id", None)
        caption    = request.form.get("caption", None)

        now         = datetime.utcnow()
        unique_id   = uuid.uuid4().hex
        secure_name = secure_filename(file.filename)
        storage_path= os.path.join(
            current_app.config["UPLOAD_FOLDER"],
            str(current_user.id),
            now.strftime("%Y/%m/%d")
        )
        os.makedirs(storage_path, exist_ok=True)

        unique_name = f"{unique_id}_{secure_name}"
        full_path   = os.path.join(storage_path, unique_name)
        file.save(full_path)

        file_url = f"/{current_user.id}/{now.strftime('%Y/%m/%d')}/{unique_name}"

        media = Media(
            plugin      = plugin,
            related_id  = related_id,
            filename    = unique_name,
            uploaded_at = now,
            uploader_id = current_user.id,
            caption     = caption,
            plant_id    = plant_id,
            growlog_id  = growlog_id,
            created_at  = now,
            file_url    = file_url
        )
        db.session.add(media)
        db.session.commit()

        flash("File uploaded and saved successfully.", "success")
        return redirect(request.url)

    # -------------------------------------------------------------------------
    # GET → render form
    # -------------------------------------------------------------------------
    return render_template("utility/upload.html", csrf_token=generate_csrf())


@bp.route("/review", methods=["GET", "POST"])
@login_required
def review():
    rows        = session.get("pending_rows", [])
    review_list = session.get("review_list", [])

    if request.method == "POST":
        neo            = get_neo4j_handler()
        added          = 0
        all_common     = {c.name.lower(): c for c in PlantCommonName.query.all()}
        all_scientific = {s.name.lower(): s for s in PlantScientificName.query.all()}

        for row in rows:
            uuid_val    = row["uuid"]
            name        = row["name"]
            sci_name    = row["sci_name"]
            suggested   = row["suggested"]
            plant_type  = row["plant_type"]
            mother_uuid = row["mother_uuid"]
            accepted    = request.form.get(f"confirm_{uuid_val}") == "yes"

            # handle names
            common = PlantCommonName.query.filter_by(name=name).first()
            if not common:
                common = PlantCommonName(name=name)
                db.session.add(common)
                db.session.flush()
            all_common[common.name.lower()] = common

            use_name  = suggested if (suggested and accepted) else sci_name
            scientific = PlantScientificName.query.filter_by(name=use_name).first()
            if not scientific:
                scientific = PlantScientificName(
                    name      = use_name,
                    common_id = common.id
                )
                db.session.add(scientific)
                db.session.flush()
            all_scientific[scientific.name.lower()] = scientific

            verified = not suggested or (suggested and accepted)
            plant = Plant.query.filter_by(uuid=uuid_val).first()
            if not plant:
                plant = Plant(
                    uuid           = uuid_val,
                    common_id      = common.id,
                    scientific_id  = scientific.id,
                    plant_type     = plant_type,
                    owner_id       = current_user.id,
                    mother_uuid    = mother_uuid or None,
                    data_verified  = verified
                )
                db.session.add(plant)
                db.session.flush()

                log = PlantOwnershipLog(
                    plant_id      = plant.id,
                    user_id       = current_user.id,
                    date_acquired = datetime.utcnow(),
                    transferred   = False,
                    is_verified   = verified
                )
                db.session.add(log)
                added += 1

            neo.create_plant_node(plant.uuid, plant.common.name)
            if mother_uuid:
                neo.create_lineage(child_uuid=plant.uuid, parent_uuid=mother_uuid)

        db.session.commit()
        neo.close()

        flash(f"{added} plants added (MySQL) and Neo4j updated.", "success")
        session.pop("pending_rows", None)
        session.pop("review_list", None)
        return redirect(url_for("utility.upload"))

    return render_template(
        "utility/review.html",
        review_list=review_list,
        csrf_token=generate_csrf()
    )


@bp.route('/export_data', methods=['GET'])
@login_required
def export_data():
    export_id = f"{uuid.uuid4()}_{int(datetime.utcnow().timestamp())}"
    plants = (
        Plant.query.filter_by(owner_id=current_user.id)
             .order_by(Plant.id).all()
    )

    # build plants.csv
    plant_io = io.StringIO()
    pw = csv.writer(plant_io)
    pw.writerow([
        'UUID','Type','Name','Scientific Name',
        'Vendor Name','Price','Mother UUID','Notes'
    ])
    for p in plants:
        pw.writerow([
            p.uuid,
            p.plant_type,
            p.common_name.name if p.common_name else '',
            p.scientific_name.name if p.scientific_name else '',
            getattr(p, 'vendor_name','') or '',
            getattr(p, 'price','') or '',
            p.mother_uuid or '',
            p.notes or ''
        ])
    plants_csv = plant_io.getvalue()

    # build media.csv
    media_records = (
        Media.query.filter(
            Media.uploader_id==current_user.id,
            Media.plant_id.isnot(None)
        ).order_by(Media.id).all()
    )
    media_io = io.StringIO()
    mw = csv.writer(media_io)
    mw.writerow(['Plant UUID','Image Path','Uploaded At','Source Type'])
    for m in media_records:
        mw.writerow([
            m.plant.uuid,
            m.file_url,
            m.uploaded_at.isoformat() if m.uploaded_at else '',
            m.caption or ''
        ])
    media_csv = media_io.getvalue()

    # assemble ZIP
    zip_buf = io.BytesIO()
    with zipfile.ZipFile(zip_buf,'w',zipfile.ZIP_DEFLATED) as zf:
        meta = (
            f"export_id,{export_id}\n"
            f"user_id,{current_user.id}\n"
            f"exported_at,{datetime.utcnow().isoformat()}\n"
        )
        zf.writestr('metadata.txt', meta)
        zf.writestr('plants.csv', plants_csv)
        zf.writestr('media.csv', media_csv)
        media_root = current_app.config['UPLOAD_FOLDER']
        for m in media_records:
            rel = m.file_url.split('uploads/',1)[-1]
            abs_path = os.path.join(media_root, rel)
            if os.path.isfile(abs_path):
                arcname = os.path.join('images', rel)
                zf.write(abs_path, arcname)
    zip_buf.seek(0)

    safe_email = re.sub(r'\W+','_',current_user.email)
    filename   = f"{safe_email}_export_{export_id}.zip"
    return send_file(
        zip_buf,
        mimetype='application/zip',
        as_attachment=True,
        download_name=filename
    )


def generate_label_with_name(qr_url, name, filename):
    from PIL import Image, ImageDraw, ImageFont
    import qrcode
    from qrcode.image.pil import PilImage
    from qrcode.constants import ERROR_CORRECT_H
    from flask import send_file

    qr = qrcode.QRCode(
        version=2,
        error_correction=ERROR_CORRECT_H,
        box_size=10,
        border=1
    )
    qr.add_data(qr_url)
    qr.make(fit=True)
    qr_img = qr.make_image(
        image_factory=PilImage,
        fill_color="black",
        back_color="white"
    ).convert("RGB")

    dpi      = 300
    label_px = int(1.5 * dpi)
    label_img= Image.new("RGB", (label_px, label_px), "white")

    qr_size  = 350
    qr_img   = qr_img.resize((qr_size, qr_size), Image.LANCZOS)
    qr_x     = (label_px - qr_size) // 2
    label_img.paste(qr_img, (qr_x, 10))

    font_path= os.path.abspath(
        os.path.join(
            current_app.root_path, '..', 'font', 'ARIALLGT.TTF'
        )
    )
    draw     = ImageDraw.Draw(label_img)
    name     = (name or '').strip()

    font_size = 28
    while font_size > 10:
        try:
            font = ImageFont.truetype(font_path, font_size)
        except OSError:
            font = ImageFont.load_default()
        if draw.textlength(name, font=font) <= label_px - 20:
            break
        font_size -= 1

    if draw.textlength(name, font=font) > label_px - 20:
        while draw.textlength(name + "…", font=font) > label_px - 20 and len(name) > 1:
            name = name[:-1]
        name += "…"

    text_x = (label_px - draw.textlength(name, font=font)) // 2
    text_y = 370
    draw.text((text_x, text_y), name, font=font, fill="black")

    buf = io.BytesIO()
    label_img.save(buf, format='PNG', dpi=(dpi, dpi))
    buf.seek(0)

    return send_file(
        buf,
        mimetype='image/png',
        as_attachment=True,
        download_name=filename
    )


@bp.route('/download_qr/<string:uuid_val>', methods=['GET'])
@login_required
def download_qr(uuid_val):
    p = Plant.query.filter_by(uuid=uuid_val, owner_id=current_user.id).first_or_404()
    if not p.short_id:
        p.short_id = Plant.generate_short_id()
        db.session.commit()
    base     = current_app.config.get('PLANT_CARDS_BASE_URL', 'https://plant.cards')
    qr_url   = f"{base}/f/{p.short_id}"
    filename = f"{p.short_id}.png"
    return generate_label_with_name(qr_url, p.common_name.name, filename)


@bp.route('/download_qr_card/<string:uuid_val>', methods=['GET'])
def download_qr_card(uuid_val):
    p = Plant.query.filter_by(uuid=uuid_val).first_or_404()
    if not p.short_id:
        p.short_id = Plant.generate_short_id()
        db.session.commit()
    base     = current_app.config.get('PLANT_CARDS_BASE_URL', 'https://plant.cards')
    qr_url   = f"{base}/{p.short_id}"
    filename = f"{p.short_id}_card.png"
    return generate_label_with_name(qr_url, p.common_name.name, filename)