import re
import datetime
import html as html_lib
import pandas as pd
from typing import List, Optional, Tuple
from pathlib import Path
from string import Template

# Import our modular components
from ..state import get_user_temp_dir, update_progress, get_pending_files, clear_pending_file
from .utils import now_str, cleanup_after_analysis, safe_float, parse_mc_or_default, parse_mc_or_none

# --- Constants for Reporting ---
CROSS_REPORT_TEMPLATE = Path(__file__).resolve().parents[1] / "templates" / "reports" / "cross-market-report.html"
SHARED_TOKENS_CSS = Path(__file__).resolve().parents[1] / "static" / "css" / "shared_tokens.css"

ORIGINAL_MATCHED_HEADERS = ["Ticker", "Spot MrktCap", "Spot Volume", "Spot VTMR", "Futures Volume", "Futures VTMR", "OISS", "Funding Rate"]
ORIGINAL_FUTURES_HEADERS = ["Ticker", "Market Cap", "Volume", "VTMR", "OISS", "Funding Rate"]
ORIGINAL_SPOT_HEADERS = ["Ticker", "MarketCap", "Volume", "VTMR"]


class SignalEngine:

    @staticmethod
    def _oi_score_and_signal(oi_change: float) -> Tuple[int, str]:
        if oi_change > 0.20: return 5, "Strong"
        if oi_change > 0.10: return 4, "Bullish"
        if oi_change > 0.00: return 3, "Build-Up"
        if oi_change > -0.10: return 2, "Weakening"
        if oi_change > -0.20: return 1, "Exiting"
        return 0, "Exiting"

    @staticmethod
    def _funding_score_and_signal(funding_val: float) -> Tuple[str, str]:
        if funding_val >= 0.05: return "Greed", "oi-strong"
        if funding_val > 0.00: return "Bullish", "oi-strong"
        if funding_val <= -0.05: return "Extreme Fear", "oi-weak"
        if funding_val < 0.00: return "Bearish", "oi-weak"
        return "Neutral", ""

    @classmethod
    def make_oiss(cls, oi_pct: Optional[float]) -> str:
        if oi_pct is None or (isinstance(oi_pct, float) and pd.isna(oi_pct)):
            return "-"
        try:
            oi_change = oi_pct / 100
            score, signal = cls._oi_score_and_signal(oi_change)

            if oi_change > 0: css_class = "oi-strong"
            elif oi_change < 0: css_class = "oi-weak"
            else: css_class = ""

            sign = "+" if oi_change > 0 else ""
            if css_class:
                return f'<span class="{css_class}">{sign}{oi_change*100:.0f}%</span> {signal}'
            return f"{sign}{oi_change*100:.0f}% {signal}"
        except Exception:
            return "-"

    @classmethod
    def make_funding_signal(cls, funding_pct: Optional[float]) -> str:
        if funding_pct is None or (isinstance(funding_pct, float) and pd.isna(funding_pct)):
            return "-"
        try:
            val = float(funding_pct)
            signal_word, css_class = cls._funding_score_and_signal(val)

            if css_class:
                return f'<span class="{css_class}">{val}%</span> <span style="font-size:0.8em; color:var(--report-muted);">{signal_word}</span>'
            return f'{val}% {signal_word}'
        except Exception:
            return "-"


class DataProcessor:
    """Handles Dataframe loading, merging, and HTML generation."""

    @staticmethod
    def format_ticker_btn(sym_val) -> str:
        """Helper method isolated to avoid scope issues."""
        sym_clean = html_lib.escape(str(sym_val).strip().upper(), quote=True)
        return f'<a href="/deep-diver?ticker={sym_clean}" class="ticker-btn">{sym_clean}</a>'

    @staticmethod
    def format_futures_money(value) -> str:
        """Adds a '$' prefix to a parseable futures market_cap/volume value; leaves n/a bare."""
        if pd.isna(value):
            return "n/a"
        s = str(value).strip()
        if s.lower() == "n/a":
            return "n/a"
        return f"${s}"

    @staticmethod
    def _caps_compatible(spot_cap, fut_cap, max_ratio: float = 5.0) -> bool:
        """Guards against cross-market ticker collisions."""
        spot_val = parse_mc_or_none(spot_cap)
        fut_val = parse_mc_or_none(fut_cap)
        if spot_val is None or fut_val is None or spot_val <= 0 or fut_val <= 0:
            return True
        ratio = max(spot_val, fut_val) / min(spot_val, fut_val)
        return ratio <= max_ratio

    @staticmethod
    def load_spot(path: Path) -> pd.DataFrame:
        print(f"   Parsing Spot File: {path.name}")
        try:
            if path.suffix == '.html':
                df = pd.read_html(str(path), encoding='utf-8')[0]
            else:
                df = pd.read_csv(path, encoding='utf-8')
            df.columns = [c.lower().replace(' ', '_') for c in df.columns]
            
            col_map = {
                'ticker': 'ticker',
                'symbol': 'ticker', 
                'vtmr': 'vtmr',         
                'spot_vtmr': 'vtmr', 
                'flipping_multiple': 'vtmr',
                'market_cap': 'market_cap',
                'marketcap': 'market_cap',
                'volume_24h': 'volume',
                'volume': 'volume'
            }
            
            df = df.rename(columns=col_map, errors='ignore')
            
            if 'ticker' not in df.columns:
                for col in df.columns:
                    if 'sym' in col or 'tick' in col or 'tok' in col:
                        df = df.rename(columns={col: 'ticker'})
                        break

            if 'ticker' in df.columns:
                df['ticker'] = df['ticker'].apply(lambda x: str(x).strip().upper())
                
            print(f"   Extracted {len(df)} spot tokens")
            return df
        except Exception as e:
            print(f"   Spot File Error: {e}")
            return pd.DataFrame()
            
    @staticmethod
    def _generate_table_html(title: str, df: pd.DataFrame, headers: List[str], df_cols: List[str]) -> str:
        if df.empty:
            return f'<div class="table-container"><h2>{title}</h2><p>No data found</p></div>'
        missing = [c for c in df_cols if c not in df.columns]
        df_display = df.copy()
        for m in missing:
            df_display[m] = ""
        df_display = df_display[df_cols]
        df_display.columns = headers
        
        SAFE_HTML_HEADERS = {"Ticker", "OISS", "Funding Rate"}
        for col in df_display.columns:
            if col not in SAFE_HTML_HEADERS:
                df_display[col] = df_display[col].apply(lambda v: html_lib.escape(str(v)))

        table_html = df_display.to_html(index=False, classes='table', escape=False)
        return f'<div class="table-container"><h2>{title}</h2>{table_html}</div>'

    @staticmethod
    def generate_html_report(futures_df: pd.DataFrame, spot_df: pd.DataFrame) -> Optional[str]:
        """Merges Spot and Futures dataframes and creates the final HTML report."""
        if futures_df.empty or spot_df.empty:
            return None

        futures_df = futures_df.copy()
        if 'oi_pct' in futures_df.columns:
            futures_df['oiss'] = futures_df['oi_pct'].apply(SignalEngine.make_oiss)
        else:
            futures_df['oiss'] = "-"

        if 'funding_pct' in futures_df.columns:
            futures_df['funding'] = futures_df['funding_pct'].apply(SignalEngine.make_funding_signal)
        else:
            futures_df['funding'] = "-"

        valid_futures = futures_df.copy()
        try:
            if 'vtmr' in valid_futures.columns:
                valid_futures['vtmr_display'] = valid_futures['vtmr'].apply(lambda x: f"{x:.2f}x")
        except Exception as e:
            print(f"   Futures display formatting error: {e}")
            valid_futures['vtmr_display'] = valid_futures['vtmr']

        merged = pd.merge(spot_df, valid_futures, on='ticker', how='inner', suffixes=('_spot', '_fut'))

        if not merged.empty and 'market_cap_spot' in merged.columns and 'market_cap_fut' in merged.columns:
            cap_ok = merged.apply(
                lambda r: DataProcessor._caps_compatible(r.get('market_cap_spot'), r.get('market_cap_fut')),
                axis=1
            )
            mismatched = merged[~cap_ok]
            if not mismatched.empty:
                print(f"   ⚠️  Excluded {len(mismatched)} ticker collision(s) from cross-market merge "
                      f"(market cap mismatch, likely different tokens sharing a symbol): "
                      f"{sorted(mismatched['ticker'].unique().tolist())}")
            merged = merged[cap_ok].copy()

        matched_tickers = set(merged['ticker'])

        if 'vtmr_fut' in merged.columns:
            merged = merged.sort_values('vtmr_fut', ascending=False)

        futures_only = valid_futures[~valid_futures['ticker'].isin(matched_tickers)].copy()
        if 'vtmr' in futures_only.columns:
            futures_only = futures_only.sort_values('vtmr', ascending=False)

        spot_only = spot_df[~spot_df['ticker'].isin(matched_tickers)].copy()
        
        if 'vtmr' in spot_only.columns:
            try:
                spot_only = spot_only.copy()
                spot_only.loc[:, 'sort_val'] = spot_only['vtmr'].astype(str).str.replace('x', '', case=False).astype(float)
                spot_only = spot_only.sort_values('sort_val', ascending=False).drop(columns=['sort_val'])
            except Exception as e:
                print(f"   Spot filtering error: {e}")

        # Map button formatting via isolated staticmethod
        if 'ticker' in merged.columns:
            merged['ticker'] = merged['ticker'].apply(DataProcessor.format_ticker_btn)
        if 'ticker' in futures_only.columns:
            futures_only['ticker'] = futures_only['ticker'].apply(DataProcessor.format_ticker_btn)
        if 'ticker' in spot_only.columns:
            spot_only['ticker'] = spot_only['ticker'].apply(DataProcessor.format_ticker_btn)
        
        merged_cols = ['ticker', 'market_cap_spot', 'volume_spot', 'vtmr_spot', 'volume_fut', 'vtmr_display', 'oiss', 'funding']
        futures_cols = ['ticker', 'market_cap', 'volume', 'vtmr_display', 'oiss', 'funding']
        spot_cols = ['ticker', 'market_cap', 'volume', 'vtmr']
        
        tables_body = ""
        tables_body += DataProcessor._generate_table_html("Tokens in Both Futures & Spot Markets", merged, ORIGINAL_MATCHED_HEADERS, merged_cols)
        tables_body += DataProcessor._generate_table_html("Remaining Futures-Only Tokens", futures_only, ORIGINAL_FUTURES_HEADERS, futures_cols)
        tables_body += DataProcessor._generate_table_html("Remaining Spot-Only Tokens", spot_only, ORIGINAL_SPOT_HEADERS, spot_cols)
        current_time = now_str("%d-%m-%Y %H:%M:%S")
        
        cheat_sheet_footer = """
            <div style="margin-top: 30px; padding: 15px; background: var(--report-guide); border-radius: 8px;">
    <h2 style="color: var(--report-head); border-bottom: 2px solid var(--report-accent); padding-bottom: 5px; margin-top: 0;">Guide to Reading the Cross‑Market Report</h2>
    <p>For a comprehensive guide on how to interpret the cross‑market report, please visit: <a href="https://www.quantvat.name.ng/2026/08/reading-quantvat-cross-market-report.html" target="_blank">here</a></p>
</div>
        """
        
        template_text = CROSS_REPORT_TEMPLATE.read_text(encoding="utf-8")
        final_document = Template(template_text).substitute(
            tokens_css=SHARED_TOKENS_CSS.read_text(encoding="utf-8"),
            current_time=current_time,
            tables_body=tables_body,
            cheat_sheet_footer=cheat_sheet_footer,
        )
        return final_document

def adv_analysis_v5(user_keys, user_id) -> None:
    """Main execution flow for Advanced Analysis."""
    print("   Scanning for files to run cross-market analysis")
    update_progress(user_id, 10, "Locating Spot and Futures files...", "active")
    
    pending = get_pending_files(user_id)
    spot_file = pending.get("spot")
    futures_file = pending.get("futures")
    if not spot_file or not futures_file:
        print("   Required files not found.")
        raise FileNotFoundError("   You Need CoinAlyze Futures PDF and Spot Market Data. Kindly Generate Spot Data And Upload Futures PDF First.")
    
    update_progress(user_id, 40, "Loading Futures and Spot data...", "active")
    spot_df = DataProcessor.load_spot(spot_file)
    try:
        futures_df = pd.read_csv(futures_file, dtype={'ticker': str}, encoding='utf-8')
        print(f"   Retrieved Futures CSV: {futures_file.name}")
    except Exception as e:
        print(f"   Futures CSV Error: {e}")
        futures_df = pd.DataFrame()

    if not futures_df.empty:
        for col in ('market_cap', 'volume'):
            if col in futures_df.columns:
                futures_df[col] = futures_df[col].apply(DataProcessor.format_futures_money)

    settings = user_keys.get("engine_settings", {}) if user_keys else {}
    MIN_F_VTMR = safe_float(settings.get('min_f_vtmr'), 0.5)
    MAX_F_VTMR = safe_float(settings.get('max_f_vtmr'), 399.0)
    MIN_F_MC = parse_mc_or_default(settings.get('min_f_mc'), 0.0)
    MAX_F_MC = parse_mc_or_default(settings.get('max_f_mc'), float('inf'))

    if not futures_df.empty and 'vtmr' in futures_df.columns:
        before_count = len(futures_df)
        futures_df = futures_df[(futures_df['vtmr'] >= MIN_F_VTMR) & (futures_df['vtmr'] <= MAX_F_VTMR)]
        print(f" Extracted {len(futures_df)} futures tokens out of {before_count} with VTMR filter applied")

    if not futures_df.empty and 'market_cap' in futures_df.columns:
        before_count = len(futures_df)
        mc_numeric = futures_df['market_cap'].apply(parse_mc_or_none)
        # Rows with missing/unparseable market cap pass through unfiltered (VTMR filter already vetted them)
        in_range = mc_numeric.isna() | ((mc_numeric >= MIN_F_MC) & (mc_numeric <= MAX_F_MC))
        futures_df = futures_df[in_range]
        print(f" Then extracted {len(futures_df)} futures tokens out of {before_count} with MC filter applied")
    
    update_progress(user_id, 65, "Merging cross-market signals...", "active")
    html_content = DataProcessor.generate_html_report(futures_df, spot_df)
    if not html_content:
        print("   No data to generate report")
        raise ValueError("No matching data between spot and futures files — check both sources.")

    update_progress(user_id, 85, "Saving report...", "active")
    timestamp = datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
    html_file = get_user_temp_dir(user_id) / f"cross-market-analysis-{timestamp}.html"
    try:
        html_file.write_text(html_content, encoding="utf-8")
    except Exception as e:
        print(f"   Report save failed: {e}")
        raise RuntimeError(f"Could not save the report: {e}")
    print(f"   Report saved as: {html_file.name}")
    cleanup_after_analysis(spot_file, futures_file, keep_spot=True)
    clear_pending_file(user_id, "futures")
    print("    Analysis completed!")