import csv
import io
from flask import Blueprint, request, render_template, redirect, flash
from werkzeug.utils import secure_filename
from app.neo4j_utils import get_neo4j_handler
from plugins.plant.models import db, Plant, PlantCommon, PlantScientific

bp = Blueprint("importer", __name__, template_folder="templates")

@bp.route("/import/", methods=["GET", "POST"])
def upload():
    if request.method == "POST":
        file = request.files.get("file")
        if not file:
            flash("No file uploaded.", "error")
            return redirect(request.url)

        try:
            # Handle UTF-8 BOM (Byte Order Mark) if present
            decoded = file.read().decode("utf-8-sig")
            stream = io.StringIO(decoded)
            reader = csv.DictReader(stream)

            neo = get_neo4j_handler()

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

                if not all([uuid, name, sci_name]):
                    continue  # skip incomplete rows

                # Common Name
                common = PlantCommon.query.filter_by(name=name).first()
                if not common:
                    common = PlantCommon(name=name)
                    db.session.add(common)
                    db.session.flush()

                # Scientific Name
                scientific = PlantScientific.query.filter_by(name=sci_name).first()
                if not scientific:
                    scientific = PlantScientific(name=sci_name, common_id=common.id)
                    db.session.add(scientific)
                    db.session.flush()

                # Plant
                plant = Plant.query.filter_by(uuid=uuid).first()
                if not plant:
                    plant = Plant(
                        uuid=uuid,
                        common_id=common.id,
                        scientific_id=scientific.id,
                        plant_type=plant_type
                    )
                    db.session.add(plant)

                # Neo4j
                neo.create_plant_node(uuid, name)
                if mother_uuid and mother_uuid.strip():
                    neo.create_plant_node(mother_uuid.strip(), "Parent")
                    neo.create_lineage(uuid, mother_uuid.strip())

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

            flash("CSV imported successfully with lineage.", "success")

        except Exception as e:
            flash(f"Import failed: {str(e)}", "error")

        return redirect(request.url)

    return render_template("importer/upload.html")