import urllib.request
import xml.etree.ElementTree as ET
import re
from datetime import datetime
import threading
import time

HEADERS = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
    'Accept-Language': 'en-US,en;q=0.5'
}

_cache = {
    "data": None,
    "last_fetched": 0
}
_diagram_cache = {}
_lock = threading.Lock()

FIELD_MAP = {
    "copper": "LME_Cu_cash",
    "cu": "LME_Cu_cash",
    "aluminium": "LME_Al_cash",
    "al": "LME_Al_cash",
    "aluminum": "LME_Al_cash",
    "zinc": "LME_Zn_cash",
    "zn": "LME_Zn_cash",
    "nickel": "LME_Ni_cash",
    "ni": "LME_Ni_cash",
    "lead": "LME_Pb_cash",
    "pb": "LME_Pb_cash",
    "tin": "LME_Sn_cash",
    "sn": "LME_Sn_cash",
}

FA_NAMES = {
    "Copper": "مس",
    "Tin": "قلع",
    "Lead": "سرب",
    "Zinc": "روی",
    "Aluminium": "آلومینیوم",
    "Nickel": "نیکل",
    "WM_Cu_low": "مس کاتد آلمان (کف قیمت)",
    "WM_Cu_high": "مس کاتد آلمان (سقف قیمت)",
    "WI_Cu": "مس ویلند (Wieland)",
    "ACI": "شاخص مس پیشرفته (ACI)",
    "MB_bronze_94_6": "برنز ۹۴/۶",
    "MB_MS_58_1": "برنج MS 58 (مرحله ۱)",
    "MB_MS_58_2": "برنج MS 58 (مرحله ۲)",
    "MB_MS_63_37": "برنج MS 63/37",
    "MB_MS_63_wire": "مفتول برنجی MS 63",
    "USD_ozt_London": "انس طلای لندن (Fixing)",
    "Au": "طلای شمش در اروپا",
    "Au_processed": "طلای ساخته‌شده در اروپا",
    "Ag": "نقره خالص در اروپا",
    "Ag_processed": "نقره ساخته‌شده در اروپا",
}

SERIES_FA_NAMES = {
    "LME Copper Cash-Settlement": "قیمت تسویه نقدی مس",
    "LME Copper stock": "موجودی انبار مس",
    "LME Aluminium Cash-Settlement": "قیمت تسویه نقدی آلومینیوم",
    "LME Aluminium stock": "موجودی انبار آلومینیوم",
    "LME Zinc Cash-Settlement": "قیمت تسویه نقدی روی",
    "LME Zinc stock": "موجودی انبار روی",
    "LME Nickel Cash-Settlement": "قیمت تسویه نقدی نیکل",
    "LME Nickel stock": "موجودی انبار نیکل",
    "LME Lead Cash-Settlement": "قیمت تسویه نقدی سرب",
    "LME Lead stock": "موجودی انبار سرب",
    "LME Tin Cash-Settlement": "قیمت تسویه نقدی قلع",
    "LME Tin stock": "موجودی انبار قلع",
    "WM_Cu_low": "کف قیمت مس کاتد آلمان",
    "WM_Cu_high": "سقف قیمت مس کاتد آلمان",
    "Gold London Fixing": "انس طلای لندن",
    "Fine Silver in Euro/kg": "نقره خالص در اروپا",
    "Gold in Euro/kg": "طلای شمش در اروپا",
    "Advanced Copper Index (ACI)": "شاخص مس پیشرفته (ACI)",
    "Wieland-Copper": "مس ویلند",
}

def clean_num(val: str) -> float:
    if not val:
        return 0.0
    val = val.replace(',', '').replace('+', '').replace('$', '').strip()
    try:
        return float(val)
    except:
        return 0.0

def fetch_raw():
    url = 'https://www.westmetall.com/en/markdaten.php'
    req = urllib.request.Request(url, headers=HEADERS)
    with urllib.request.urlopen(req, timeout=12) as resp:
        html = resp.read().decode('utf-8', errors='ignore')

    tables = re.findall(r'<table[^>]*>([\s\S]*?)</table>', html)
    if len(tables) < 2:
        return None

    # Table 0: Official LME Prices
    t0_rows = re.findall(r'<tr[^>]*>([\s\S]*?)</tr>', tables[0])
    date_str = ""
    prices = []
    if t0_rows:
        header_cells = re.findall(r'<t[dh][^>]*>([\s\S]*?)</t[dh]>', t0_rows[0])
        if len(header_cells) > 1:
            date_str = re.sub(r'<.*?>', '', header_cells[1]).strip()

        for r in t0_rows[2:]:
            cells = [re.sub(r'<.*?>', '', c).replace('&nbsp;', ' ').strip() for c in re.findall(r'<t[dh][^>]*>([\s\S]*?)</t[dh]>', r)]
            links = re.findall(r'field=([a-zA-Z0-9_]+)', r)
            field = links[0] if links else f"LME_{cells[0][:2]}_cash"
            if len(cells) >= 3 and cells[0]:
                prices.append({
                    "metal": cells[0],
                    "name_fa": FA_NAMES.get(cells[0], cells[0]),
                    "field": field,
                    "cash": clean_num(cells[1]),
                    "cash_str": cells[1],
                    "three_months": clean_num(cells[2]),
                    "three_months_str": cells[2],
                    "unit": "دلار بر تن"
                })

    # Table 1: LME Stocks
    t1_rows = re.findall(r'<tr[^>]*>([\s\S]*?)</tr>', tables[1])
    stocks = []
    if len(t1_rows) > 2:
        for r in t1_rows[2:]:
            cells = [re.sub(r'<.*?>', '', c).replace('&nbsp;', ' ').strip() for c in re.findall(r'<t[dh][^>]*>([\s\S]*?)</t[dh]>', r)]
            links = re.findall(r'field=([a-zA-Z0-9_]+)', r)
            field = links[0] if links else ""
            if len(cells) >= 3 and cells[0]:
                stocks.append({
                    "metal": cells[0],
                    "name_fa": FA_NAMES.get(cells[0], cells[0]),
                    "field": field,
                    "stocks": clean_num(cells[1]),
                    "stocks_str": cells[1],
                    "change": clean_num(cells[2]),
                    "change_str": cells[2],
                    "unit": "تن"
                })

    # Combine Prices + Stocks by metal
    combined_metals = []
    stocks_map = {s["metal"]: s for s in stocks}
    for p in prices:
        m_name = p["metal"]
        s_data = stocks_map.get(m_name, {})
        spread = round(p["three_months"] - p["cash"], 2)
        combined_metals.append({
            "metal": m_name,
            "name_fa": p["name_fa"],
            "field": p["field"],
            "cash_settlement": p["cash"],
            "cash_str": p["cash_str"],
            "three_months": p["three_months"],
            "three_months_str": p["three_months_str"],
            "spread": spread,
            "spread_str": f"{spread:+,.2f}",
            "stocks": s_data.get("stocks", 0),
            "stocks_str": s_data.get("stocks_str", "-"),
            "stocks_change": s_data.get("change", 0),
            "stocks_change_str": s_data.get("change_str", "-"),
            "unit": "دلار بر تن"
        })

    # Table 2: FX Rates
    fx = []
    if len(tables) > 2:
        for r in re.findall(r'<tr[^>]*>([\s\S]*?)</tr>', tables[2])[1:]:
            cells = [re.sub(r'<.*?>', '', c).replace('&nbsp;', ' ').strip() for c in re.findall(r'<t[dh][^>]*>([\s\S]*?)</t[dh]>', r)]
            if len(cells) >= 2 and cells[0]:
                fx.append({
                    "pair": cells[0],
                    "rate": clean_num(cells[1]),
                    "rate_str": cells[1]
                })

    # Table 3: German Metal Quotations
    german_symbols = []
    if len(tables) > 3:
        for r in re.findall(r'<tr[^>]*>([\s\S]*?)</tr>', tables[3])[2:]:
            cells = [re.sub(r'<.*?>', '', c).replace('&nbsp;', ' ').strip() for c in re.findall(r'<t[dh][^>]*>([\s\S]*?)</t[dh]>', r)]
            links = re.findall(r'field=([a-zA-Z0-9_]+)', r)
            field = links[0] if links else ""
            if len(cells) >= 3 and cells[0]:
                german_symbols.append({
                    "name": cells[0],
                    "name_fa": FA_NAMES.get(field, cells[0]),
                    "field": field,
                    "price_str": cells[1],
                    "prev_str": cells[2],
                    "unit": "یورو بر ۱۰۰ کیلوگرم"
                })

    # Table 4: Precious Metals
    precious = []
    if len(tables) > 4:
        for r in re.findall(r'<tr[^>]*>([\s\S]*?)</tr>', tables[4])[1:]:
            cells = [re.sub(r'<.*?>', '', c).replace('&nbsp;', ' ').strip() for c in re.findall(r'<t[dh][^>]*>([\s\S]*?)</t[dh]>', r)]
            links = re.findall(r'field=([a-zA-Z0-9_]+)', r)
            field = links[0] if links else ""
            if len(cells) >= 2 and cells[0]:
                precious.append({
                    "name": cells[0],
                    "name_fa": FA_NAMES.get(field, cells[0]),
                    "field": field,
                    "price_str": cells[1],
                    "prev_str": cells[2] if len(cells) > 2 else "-"
                })

    return {
        "date": date_str or datetime.utcnow().strftime("%d. %B %Y"),
        "updated_at": datetime.utcnow().isoformat(),
        "metals": combined_metals,
        "stocks": stocks,
        "german_symbols": german_symbols,
        "exchange_rates": fx,
        "precious_metals": precious
    }

def get_lme_data(ttl_seconds: int = 21600): # 6 hours cache
    now = time.time()
    with _lock:
        if _cache["data"] and (now - _cache["last_fetched"]) < ttl_seconds:
            return _cache["data"]
        try:
            fresh = fetch_raw()
            if fresh:
                _cache["data"] = fresh
                _cache["last_fetched"] = now
                return fresh
        except Exception as e:
            if _cache["data"]:
                return _cache["data"]
            raise e
        return _cache["data"]

def get_entire_diagram_data(field: str, ttl_seconds: int = 21600): # 6 hours cache
    field_clean = field.strip()
    field_clean = FIELD_MAP.get(field_clean.lower(), field_clean)

    now = time.time()
    with _lock:
        cached = _diagram_cache.get(field_clean)
        if cached and (now - cached["time"]) < ttl_seconds:
            return cached["data"]

    url = f'https://www.westmetall.com/api/marketdata/en/{field_clean}/'
    req = urllib.request.Request(url, headers=HEADERS)
    with urllib.request.urlopen(req, timeout=15) as r:
        xml_text = r.read().decode('utf-8')

    root = ET.fromstring(xml_text)
    series_elem = root.find('series')
    if series_elem is None:
        return {"field": field_clean, "lines": []}

    lines = []
    for line in series_elem:
        raw_name = line.attrib.get('name', field_clean)
        fa_line_name = SERIES_FA_NAMES.get(raw_name, raw_name)
        color = line.attrib.get('lineColor', '#D02E00')
        raw_unit = line.attrib.get('yUnit', '')
        precision = int(line.attrib.get('yPrecision', '2'))

        # Persian unit & type
        is_stock = "stock" in raw_name.lower() or "bestände" in raw_name.lower() or "انبار" in fa_line_name
        if is_stock:
            unit = "تن"
            series_type = "stocks"
            color = "#f97316" # vibrant orange for stocks
        elif "€" in raw_unit or "euro" in raw_unit.lower():
            unit = "یورو"
            series_type = "price"
            color = "#D02E00" # red for primary price
        elif "$" in raw_unit or "usd" in raw_unit.lower():
            unit = "دلار"
            series_type = "price"
            color = "#D02E00"
        else:
            unit = raw_unit
            series_type = "price"

        pts = []
        last_valid_y = None
        for val in line:
            raw_x = val.attrib.get('x', '') # YYYY/MM/DD
            date_iso = raw_x.replace('/', '-')
            parts = date_iso.split('-')
            date_display = f"{parts[0]}/{parts[1]}/{parts[2]}" if len(parts) == 3 else date_iso

            y_str = val.attrib.get('y', '0').replace(',', '')
            try:
                y_val = float(y_str)
            except:
                y_val = 0.0

            # Filter out bank holiday / reporting zero anomalies (e.g. market closed)
            if y_val <= 0:
                if last_valid_y is not None:
                    y_val = last_valid_y
                else:
                    continue
            else:
                last_valid_y = y_val

            pts.append({
                "x": date_iso,
                "date_display": date_display,
                "y": y_val
            })

        lines.append({
            "name": fa_line_name,
            "raw_name": raw_name,
            "series_type": series_type,
            "color": color,
            "unit": unit,
            "precision": precision,
            "count": len(pts),
            "points": pts
        })

    result = {
        "field": field_clean,
        "name_fa": FA_NAMES.get(field_clean, field_clean),
        "total_points": lines[0]["count"] if lines else 0,
        "lines": lines
    }

    with _lock:
        _diagram_cache[field_clean] = {"time": now, "data": result}

    return result

def get_metal_history(metal_key: str, ttl_seconds: int = 300):
    return get_entire_diagram_data(metal_key, ttl_seconds)