"""
Import Covance kit inventory CSV do MySQL tabulky covance_kit_inventory.
Strategie: versioning — každý import = nový import_id.
Metadata řádky na konci CSV (začínají "title" / "Search" / ...) jsou ignorovány.
"""

import os
import glob
import datetime

import numpy as np
import pandas as pd
import mysql.connector

import db_config

STUDY      = "42847922MDD3003"
SOURCE_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)), "SourceData")


# ── type converters ──────────────────────────────────────────────────────────

def _py(val):
    if isinstance(val, np.generic):
        return val.item()
    return val

def to_str(val):
    val = _py(val)
    if val is None:
        return None
    if isinstance(val, float) and (val != val):
        return None
    s = str(val).strip()
    return None if s.lower() in ("nan", "nat", "none", "") else s

def to_int(val):
    val = _py(val)
    try:
        v = float(val)
        return None if (v != v) else int(v)
    except (TypeError, ValueError):
        return None

def to_date(val):
    val = _py(val)
    if val is None:
        return None
    if isinstance(val, float) and (val != val):
        return None
    try:
        if pd.isna(val):
            return None
    except (TypeError, ValueError):
        pass
    if isinstance(val, pd.Timestamp):
        return None if pd.isna(val) else val.date()
    if isinstance(val, datetime.datetime):
        return val.date()
    if isinstance(val, datetime.date):
        return val
    s = str(val).strip()
    if not s or s.lower() in ("nat", "nan", "none", ""):
        return None
    for fmt in ("%b %d, %Y", "%d-%b-%Y", "%Y-%m-%d", "%d-%m-%Y"):
        try:
            return datetime.datetime.strptime(s, fmt).date()
        except ValueError:
            pass
    return None


# ── DB helpers ───────────────────────────────────────────────────────────────

def get_conn():
    return mysql.connector.connect(
        host=db_config.DB_HOST, port=db_config.DB_PORT,
        user=db_config.DB_USER, password=db_config.DB_PASSWORD,
        database=db_config.DB_NAME,
    )

def insert_import(cursor, study, source_file):
    cursor.execute(
        "INSERT INTO iwrs_import (study, imported_at, source_file, report_type) VALUES (%s, %s, %s, %s)",
        (study, datetime.datetime.now(), source_file, "covance_kit_inventory"),
    )
    return cursor.lastrowid


# ── parser ───────────────────────────────────────────────────────────────────

def find_csv(study):
    pattern = os.path.join(SOURCE_DIR, f"Protocol {study} sponsor-study-*kit-inventory*.csv")
    files = glob.glob(pattern)
    if not files:
        raise FileNotFoundError(f"Nenalezen CSV soubor: {pattern}")
    return sorted(files)[-1]

def parse_site(site_str):
    """'CZ10004 - Dr. Erik Herman'  →  ('CZ10004', 'Dr. Erik Herman')"""
    if not site_str:
        return None, None
    parts = site_str.split(" - ", 1)
    code = parts[0].strip()
    name = parts[1].strip() if len(parts) > 1 else None
    return code, name

def parse_csv(path):
    df = pd.read_csv(path, dtype=str)
    # odstraň metadata řádky na konci (Project No. není číslo)
    df = df[pd.to_numeric(df["Project No."], errors="coerce").notna()].copy()

    rows = []
    for _, r in df.iterrows():
        site_code, investigator_name = parse_site(to_str(r.get("Site")))
        rows.append({
            "project_no":         to_str(r.get("Project No.")),
            "region":             to_str(r.get("Region")),
            "country":            to_str(r.get("Country")),
            "site_code":          site_code,
            "investigator_name":  investigator_name,
            "kit_type":           to_str(r.get("Kit Type")),
            "description":        to_str(r.get("Description")),
            "accession":          to_str(r.get("Accession")),
            "shipped_date":       to_date(r.get("Shipped Date")),
            "expiration_date":    to_date(r.get("Expiration Date")),
            "days_to_expiration": to_int(r.get("Days to Expiration")),
        })
    return rows


# ── insert ───────────────────────────────────────────────────────────────────

def insert_kits(cursor, import_id, rows):
    sql = """INSERT INTO covance_kit_inventory
        (import_id, study, project_no, region, country, site_code, investigator_name,
         kit_type, description, accession, shipped_date, expiration_date, days_to_expiration)
        VALUES (%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)"""
    for r in rows:
        cursor.execute(sql, (
            import_id, STUDY,
            r["project_no"], r["region"], r["country"],
            r["site_code"], r["investigator_name"],
            r["kit_type"], r["description"], r["accession"],
            r["shipped_date"], r["expiration_date"], r["days_to_expiration"],
        ))


# ── main ─────────────────────────────────────────────────────────────────────

def main():
    csv_path = find_csv(STUDY)
    print(f"Soubor: {os.path.basename(csv_path)}")

    rows = parse_csv(csv_path)
    print(f"Načteno řádků: {len(rows)}")

    conn = get_conn()
    cursor = conn.cursor()

    import_id = insert_import(cursor, STUDY, os.path.basename(csv_path))
    print(f"import_id = {import_id}")

    insert_kits(cursor, import_id, rows)
    conn.commit()
    cursor.close()
    conn.close()

    print(f"Hotovo — {len(rows)} kitů importováno.")


main()