using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using FinlyticCore.Clients;
using FinlyticCore.Dtos.Fundamentals;
using FinlyticCore.Dtos.Yahoo;
using FinlyticCore.Models.Settings;
using FinlyticCore.Services;
using FinlyticCore.Utils;
using Microsoft.Extensions.Configuration;

namespace FinlyticCore.Services.Yahoo;

public interface IYahooFinanceScraper
{
    /// <summary>
    /// Ermittelt den primären Börsenticker zu einer ISIN anhand von Börsenplatz-Prioritäten.
    /// </summary>
    Task<TickerInfoDto?> ResolveTickerFromIsinAsync(string isin, CancellationToken cancellationToken = default);

    /// <summary>
    /// Ermittelt alle gefundenen Börsenticker zu einer ISIN, sortiert nach Priorität.
    /// </summary>
    Task<List<TickerInfoDto>> ResolveAllTickersFromIsinAsync(string isin, CancellationToken cancellationToken = default);

    /// <summary>
    /// Ruft Fundamental- und Unternehmensdaten primär über die Yahoo Finance API ab
    /// und fällt automatisch auf den Playwright HTML Scraper zurück, falls keine Daten vorhanden sind.
    /// </summary>
    Task<YahooQuoteSummaryModulesDto?> GetQuoteSummaryModulesAsync(
        string symbolOrIsin,
        bool forceHtmlScrape = false,
        bool includeProfile = true,
        CancellationToken cancellationToken = default);
}

public class YahooFinanceScraper : IYahooFinanceScraper
{
    private const string _serviceName = nameof(YahooFinanceScraper);
    private readonly YahooFinanceClient _yahooApiClient;
    private readonly IYahooFinanceHtmlClient _htmlScraperClient;
    private readonly IConfiguration _configuration;
    private readonly IFinlyticLogger<YahooFinanceScraper> _finlyticLogger;

    public YahooFinanceScraper(
        YahooFinanceClient yahooApiClient,
        IYahooFinanceHtmlClient htmlScraperClient,
        IConfiguration configuration,
        IFinlyticLogger<YahooFinanceScraper> finlyticLogger)
    {
        _yahooApiClient = yahooApiClient;
        _htmlScraperClient = htmlScraperClient;
        _configuration = configuration;
        _finlyticLogger = finlyticLogger;
    }

    /// <inheritdoc />
    public async Task<TickerInfoDto?> ResolveTickerFromIsinAsync(string isin, CancellationToken cancellationToken = default)
    {
        var tickers = await ResolveAllTickersFromIsinAsync(isin, cancellationToken);
        return tickers.FirstOrDefault();
    }

    /// <inheritdoc />
    public async Task<List<TickerInfoDto>> ResolveAllTickersFromIsinAsync(string isin, CancellationToken cancellationToken = default)
    {
        if (string.IsNullOrWhiteSpace(isin)) return new List<TickerInfoDto>();

        var cleanIsin = isin.Trim().ToUpperInvariant();
        var symbols = new List<(string symbol, string exchange, int priority)>();

        // Crypto / Trade Republic interne ISINs (beginnend mit 'X', z. B. XF000BTC0017)
        if (cleanIsin.StartsWith("X", StringComparison.OrdinalIgnoreCase))
        {
            var (cryptoSubtitle, cryptoName) = await CryptoSubtitleResolver.ResolveCryptoInfoAsync(
                cleanIsin, _configuration.GetConnectionString("DefaultConnection"), cancellationToken);

            if (!string.IsNullOrWhiteSpace(cryptoSubtitle))
            {
                var cryptoEur = $"{cryptoSubtitle}-EUR";
                var cryptoUsd = $"{cryptoSubtitle}-USD";

                symbols.Add((cryptoEur, "Crypto", 0));
                symbols.Add((cryptoUsd, "Crypto", 1));

                try
                {
                    var searchRes = await _yahooApiClient.SearchAsync(cryptoSubtitle, quotesCount: 10, cancellationToken: cancellationToken);
                    if (searchRes?.Quotes != null)
                    {
                        foreach (var q in searchRes.Quotes.Where(q => !string.IsNullOrEmpty(q.Symbol)))
                        {
                            if (!symbols.Any(s => s.symbol.Equals(q.Symbol, StringComparison.OrdinalIgnoreCase)))
                            {
                                symbols.Add((q.Symbol, q.Exchange ?? "Crypto", 2));
                            }
                        }
                    }
                }
                catch (Exception ex)
                {
                    await _finlyticLogger.LogWarningAsync(CoreSettingKeys.YahooClientChannel, ex,
                        $"[{_serviceName}] Crypto search failed for {cryptoSubtitle}");
                }

                await _finlyticLogger.LogInfoAsync(CoreSettingKeys.FundamentalsChannel,
                    $"[{_serviceName}] Resolved Crypto ISIN {cleanIsin} to {cryptoEur} using Subtitle {cryptoSubtitle}");

                return symbols
                    .OrderBy(s => s.priority)
                    .Select(s => new TickerInfoDto { Ticker = s.symbol, Exchange = s.exchange })
                    .ToList();
            }
        }

        try
        {
            // 1. Suche via ISIN - der allererste Ticker von Yahoo Finance ist der absolute Primary Ticker
            var primary = await _yahooApiClient.SearchAsync(cleanIsin, quotesCount: 20, cancellationToken: cancellationToken);
            var quotes = primary?.Quotes ?? new List<YahooSearchQuoteDto>();
            var validQuotes = quotes.Where(q => !string.IsNullOrEmpty(q.Symbol)).ToList();

            if (validQuotes.Count > 0)
            {
                var first = validQuotes[0];
                symbols.Add((first.Symbol, first.Exchange ?? string.Empty, 0));

                foreach (var q in validQuotes.Skip(1))
                {
                    if (!symbols.Any(s => s.symbol.Equals(q.Symbol, StringComparison.OrdinalIgnoreCase)))
                    {
                        symbols.Add((q.Symbol, q.Exchange ?? string.Empty, Math.Max(1, GetExchangePriority(q.Symbol, cleanIsin))));
                    }
                }
            }

            // 2. Falls Ticker gefunden, mit Unternehmensname noch mehr internationale Exchangeticker suchen (z.B. APC.DE)
            if (validQuotes.Count > 0)
            {
                var companyName = validQuotes[0].LongName ?? validQuotes[0].ShortName;
                if (!string.IsNullOrWhiteSpace(companyName))
                {
                    var secondary = await _yahooApiClient.SearchAsync(companyName, quotesCount: 20, cancellationToken: cancellationToken);
                    foreach (var q in secondary?.Quotes ?? new List<YahooSearchQuoteDto>())
                    {
                        if (!string.IsNullOrEmpty(q.Symbol) &&
                            !symbols.Any(s => s.symbol.Equals(q.Symbol, StringComparison.OrdinalIgnoreCase)))
                        {
                            symbols.Add((q.Symbol, q.Exchange ?? string.Empty, Math.Max(1, GetExchangePriority(q.Symbol, cleanIsin))));
                        }
                    }
                }
            }
        }
        catch (Exception ex)
        {
            await _finlyticLogger.LogWarningAsync(CoreSettingKeys.YahooClientChannel, ex,
                $"[{_serviceName}] Fehler beim Auflösen des Tickers für ISIN '{cleanIsin}'");
        }

        var result = symbols
            .OrderBy(s => s.priority)
            .Select(s => new TickerInfoDto
            {
                Ticker = s.symbol,
                Exchange = !string.IsNullOrWhiteSpace(s.exchange) ? s.exchange : "Unknown"
            })
            .DistinctBy(s => s.Ticker, StringComparer.OrdinalIgnoreCase)
            .ToList();

        return result;
    }

    /// <inheritdoc />
    public async Task<YahooQuoteSummaryModulesDto?> GetQuoteSummaryModulesAsync(
        string symbolOrIsin,
        bool forceHtmlScrape = false,
        bool includeProfile = true,
        CancellationToken cancellationToken = default)
    {
        if (string.IsNullOrWhiteSpace(symbolOrIsin)) return null;

        var symbol = symbolOrIsin.Trim().ToUpperInvariant();

        // Falls eine ISIN übergeben wurde, zuerst Ticker auflösen
        if (IsIsin(symbol))
        {
            var resolvedTicker = await ResolveTickerFromIsinAsync(symbol, cancellationToken);
            if (resolvedTicker != null)
            {
                symbol = resolvedTicker.Ticker;
            }
        }

        YahooQuoteSummaryModulesDto? apiModules = null;

        // -------------------------------------------------------------
        // 1. PRIMÄRE DATENQUELLE: Yahoo Finance API (Cookie/Crumb)
        // -------------------------------------------------------------
        if (!forceHtmlScrape)
        {
            try
            {
                await _finlyticLogger.LogInfoAsync(CoreSettingKeys.YahooClientChannel,
                    $"[{_serviceName}] Starte primären API-Abruf für '{symbol}'...");

                var apiResponse = await _yahooApiClient.GetFullQuoteSummaryAsync(symbol, cancellationToken);
                apiModules = apiResponse?.QuoteSummary?.Result?.FirstOrDefault();

                if (apiModules != null && HasSufficientData(apiModules))
                {
                    await _finlyticLogger.LogInfoAsync(CoreSettingKeys.YahooClientChannel,
                        $"[{_serviceName}] Erfolgreich Daten über API bezogen für '{symbol}'.");
                    return apiModules;
                }

                await _finlyticLogger.LogWarningAsync(CoreSettingKeys.YahooClientChannel,
                    $"[{_serviceName}] API lieferte unvollständige Daten für '{symbol}'. Initiiere Fallback...");
            }
            catch (Exception ex)
            {
                await _finlyticLogger.LogWarningAsync(CoreSettingKeys.YahooClientChannel, ex,
                    $"[{_serviceName}] API-Abruf fehlgeschlagen für '{symbol}'. Wechsle zu Scraper...");
            }
        }

        // -------------------------------------------------------------
        // 2. FALLBACK DATENQUELLE: Playwright HTML Scraper
        // -------------------------------------------------------------
        YahooQuoteSummaryModulesDto? htmlModules = null;
        try
        {
            await _finlyticLogger.LogInfoAsync(CoreSettingKeys.YahooClientChannel,
                $"[{_serviceName}] Starte HTML-Scraper Fallback für '{symbol}' (IncludeProfile: {includeProfile})...");

            htmlModules = await _htmlScraperClient.ScrapeQuoteSummaryModulesAsync(symbol, includeProfile, cancellationToken);
        }
        catch (Exception ex)
        {
            await _finlyticLogger.LogErrorAsync(CoreSettingKeys.YahooClientChannel, ex,
                $"[{_serviceName}] HTML-Scraper Fallback ebenfalls fehlgeschlagen für '{symbol}'.");
        }

        // -------------------------------------------------------------
        // 3. Zusammenführen (Merge API & HTML Fallback)
        // -------------------------------------------------------------
        if (apiModules == null) return htmlModules;
        if (htmlModules == null) return apiModules;

        return MergeModules(apiModules, htmlModules);
    }

    private static bool HasSufficientData(YahooQuoteSummaryModulesDto modules)
    {
        return modules.SummaryDetail != null ||
               modules.FinancialData != null ||
               modules.DefaultKeyStatistics != null;
    }

    public static YahooQuoteSummaryModulesDto? MergeModules(
        YahooQuoteSummaryModulesDto? primary,
        YahooQuoteSummaryModulesDto? secondary)
    {
        if (primary == null && secondary == null) return null;
        if (primary == null) return secondary;
        if (secondary == null) return primary;

        return new YahooQuoteSummaryModulesDto(
            QuoteType: primary.QuoteType ?? secondary.QuoteType,
            AssetProfile: primary.AssetProfile ?? secondary.AssetProfile,
            FinancialData: MergeFinancialData(primary.FinancialData, secondary.FinancialData),
            DefaultKeyStatistics: MergeDefaultKeyStatistics(primary.DefaultKeyStatistics, secondary.DefaultKeyStatistics),
            SummaryDetail: MergeSummaryDetail(primary.SummaryDetail, secondary.SummaryDetail),
            IncomeStatementHistory: primary.IncomeStatementHistory ?? secondary.IncomeStatementHistory,
            IncomeStatementHistoryQuarterly: primary.IncomeStatementHistoryQuarterly ?? secondary.IncomeStatementHistoryQuarterly,
            BalanceSheetHistory: primary.BalanceSheetHistory ?? secondary.BalanceSheetHistory,
            BalanceSheetHistoryQuarterly: primary.BalanceSheetHistoryQuarterly ?? secondary.BalanceSheetHistoryQuarterly,
            CashflowStatementHistory: primary.CashflowStatementHistory ?? secondary.CashflowStatementHistory,
            CashflowStatementHistoryQuarterly: primary.CashflowStatementHistoryQuarterly ?? secondary.CashflowStatementHistoryQuarterly,
            CalendarEvents: primary.CalendarEvents ?? secondary.CalendarEvents
        );
    }

    private static YahooFinancialDataDto? MergeFinancialData(YahooFinancialDataDto? a, YahooFinancialDataDto? b)
    {
        if (a == null) return b;
        if (b == null) return a;

        return new YahooFinancialDataDto(
            CurrentPrice: a.CurrentPrice ?? b.CurrentPrice,
            TargetHighPrice: a.TargetHighPrice ?? b.TargetHighPrice,
            TargetLowPrice: a.TargetLowPrice ?? b.TargetLowPrice,
            TargetMeanPrice: a.TargetMeanPrice ?? b.TargetMeanPrice,
            TargetMedianPrice: a.TargetMedianPrice ?? b.TargetMedianPrice,
            RecommendationMean: a.RecommendationMean ?? b.RecommendationMean,
            RecommendationKey: !string.IsNullOrWhiteSpace(a.RecommendationKey) && a.RecommendationKey != "none" ? a.RecommendationKey : b.RecommendationKey,
            NumberOfAnalystOpinions: a.NumberOfAnalystOpinions ?? b.NumberOfAnalystOpinions,
            TotalCash: a.TotalCash ?? b.TotalCash,
            TotalCashPerShare: a.TotalCashPerShare ?? b.TotalCashPerShare,
            Ebitda: a.Ebitda ?? b.Ebitda,
            TotalDebt: a.TotalDebt ?? b.TotalDebt,
            QuickRatio: a.QuickRatio ?? b.QuickRatio,
            CurrentRatio: a.CurrentRatio ?? b.CurrentRatio,
            TotalRevenue: a.TotalRevenue ?? b.TotalRevenue,
            DebtToEquity: a.DebtToEquity ?? b.DebtToEquity,
            RevenuePerShare: a.RevenuePerShare ?? b.RevenuePerShare,
            ReturnOnAssets: a.ReturnOnAssets ?? b.ReturnOnAssets,
            ReturnOnEquity: a.ReturnOnEquity ?? b.ReturnOnEquity,
            GrossProfits: a.GrossProfits ?? b.GrossProfits,
            FreeCashflow: a.FreeCashflow ?? b.FreeCashflow,
            OperatingCashflow: a.OperatingCashflow ?? b.OperatingCashflow,
            RevenueGrowth: a.RevenueGrowth ?? b.RevenueGrowth,
            GrossMargins: a.GrossMargins ?? b.GrossMargins,
            EbitdaMargins: a.EbitdaMargins ?? b.EbitdaMargins,
            OperatingMargins: a.OperatingMargins ?? b.OperatingMargins,
            ProfitMargins: a.ProfitMargins ?? b.ProfitMargins,
            FinancialCurrency: a.FinancialCurrency ?? b.FinancialCurrency
        );
    }

    private static YahooDefaultKeyStatisticsDto? MergeDefaultKeyStatistics(YahooDefaultKeyStatisticsDto? a, YahooDefaultKeyStatisticsDto? b)
    {
        if (a == null) return b;
        if (b == null) return a;

        return new YahooDefaultKeyStatisticsDto(
            PriceToBook: a.PriceToBook ?? b.PriceToBook,
            EnterpriseValue: a.EnterpriseValue ?? b.EnterpriseValue,
            ForwardPE: a.ForwardPE ?? b.ForwardPE,
            ProfitMargins: a.ProfitMargins ?? b.ProfitMargins,
            FloatShares: a.FloatShares ?? b.FloatShares,
            SharesOutstanding: a.SharesOutstanding ?? b.SharesOutstanding,
            SharesShort: a.SharesShort ?? b.SharesShort,
            SharesShortPriorMonth: a.SharesShortPriorMonth ?? b.SharesShortPriorMonth,
            SharesShortPreviousMonthDate: a.SharesShortPreviousMonthDate ?? b.SharesShortPreviousMonthDate,
            DateShortInterest: a.DateShortInterest ?? b.DateShortInterest,
            SharesPercentSharesOut: a.SharesPercentSharesOut ?? b.SharesPercentSharesOut,
            HeldPercentInsiders: a.HeldPercentInsiders ?? b.HeldPercentInsiders,
            HeldPercentInstitutions: a.HeldPercentInstitutions ?? b.HeldPercentInstitutions,
            ShortRatio: a.ShortRatio ?? b.ShortRatio,
            ShortPercentOfFloat: a.ShortPercentOfFloat ?? b.ShortPercentOfFloat,
            Beta: a.Beta ?? b.Beta,
            Category: a.Category ?? b.Category,
            BookValue: a.BookValue ?? b.BookValue,
            PriceToSalesTrailing12Months: a.PriceToSalesTrailing12Months ?? b.PriceToSalesTrailing12Months,
            LastFiscalYearEnd: a.LastFiscalYearEnd ?? b.LastFiscalYearEnd,
            NextFiscalYearEnd: a.NextFiscalYearEnd ?? b.NextFiscalYearEnd,
            MostRecentQuarter: a.MostRecentQuarter ?? b.MostRecentQuarter,
            EarningsQuarterlyGrowth: a.EarningsQuarterlyGrowth ?? b.EarningsQuarterlyGrowth,
            NetIncomeToCommon: a.NetIncomeToCommon ?? b.NetIncomeToCommon,
            TrailingEps: a.TrailingEps ?? b.TrailingEps,
            ForwardEps: a.ForwardEps ?? b.ForwardEps,
            PegRatio: a.PegRatio ?? b.PegRatio,
            EnterpriseToRevenue: a.EnterpriseToRevenue ?? b.EnterpriseToRevenue,
            EnterpriseToEbitda: a.EnterpriseToEbitda ?? b.EnterpriseToEbitda,
            FiftyTwoWeekChange: a.FiftyTwoWeekChange ?? b.FiftyTwoWeekChange,
            SandP52WeekChange: a.SandP52WeekChange ?? b.SandP52WeekChange
        );
    }

    private static YahooSummaryDetailDto? MergeSummaryDetail(YahooSummaryDetailDto? a, YahooSummaryDetailDto? b)
    {
        if (a == null) return b;
        if (b == null) return a;

        return new YahooSummaryDetailDto(
            MaxAge: a.MaxAge ?? b.MaxAge,
            PriceHint: a.PriceHint ?? b.PriceHint,
            PreviousClose: a.PreviousClose ?? b.PreviousClose,
            Open: a.Open ?? b.Open,
            DayLow: a.DayLow ?? b.DayLow,
            DayHigh: a.DayHigh ?? b.DayHigh,
            RegularMarketPreviousClose: a.RegularMarketPreviousClose ?? b.RegularMarketPreviousClose,
            RegularMarketOpen: a.RegularMarketOpen ?? b.RegularMarketOpen,
            RegularMarketDayLow: a.RegularMarketDayLow ?? b.RegularMarketDayLow,
            RegularMarketDayHigh: a.RegularMarketDayHigh ?? b.RegularMarketDayHigh,
            DividendRate: a.DividendRate ?? b.DividendRate,
            DividendYield: a.DividendYield ?? b.DividendYield,
            ExDividendDate: a.ExDividendDate ?? b.ExDividendDate,
            PayoutRatio: a.PayoutRatio ?? b.PayoutRatio,
            FiveYearAvgDividendYield: a.FiveYearAvgDividendYield ?? b.FiveYearAvgDividendYield,
            Beta: a.Beta ?? b.Beta,
            TrailingPE: a.TrailingPE ?? b.TrailingPE,
            ForwardPE: a.ForwardPE ?? b.ForwardPE,
            Volume: a.Volume ?? b.Volume,
            RegularMarketVolume: a.RegularMarketVolume ?? b.RegularMarketVolume,
            AverageVolume: a.AverageVolume ?? b.AverageVolume,
            AverageVolume10days: a.AverageVolume10days ?? b.AverageVolume10days,
            AverageDailyVolume10Day: a.AverageDailyVolume10Day ?? b.AverageDailyVolume10Day,
            Bid: a.Bid ?? b.Bid,
            Ask: a.Ask ?? b.Ask,
            BidSize: a.BidSize ?? b.BidSize,
            AskSize: a.AskSize ?? b.AskSize,
            MarketCap: a.MarketCap ?? b.MarketCap,
            FiftyTwoWeekLow: a.FiftyTwoWeekLow ?? b.FiftyTwoWeekLow,
            FiftyTwoWeekHigh: a.FiftyTwoWeekHigh ?? b.FiftyTwoWeekHigh,
            PriceToSalesTrailing12Months: a.PriceToSalesTrailing12Months ?? b.PriceToSalesTrailing12Months,
            Currency: a.Currency ?? b.Currency
        );
    }

    private static bool IsIsin(string value)
    {
        return value.Length == 12 &&
               char.IsLetter(value[0]) &&
               char.IsLetter(value[1]) &&
               value.All(char.IsLetterOrDigit);
    }

    private static int GetExchangePriority(string symbol, string isin)
    {
        bool isGermanIsin = isin.StartsWith("DE", StringComparison.OrdinalIgnoreCase);

        if (isGermanIsin)
        {
            if (symbol.EndsWith(".DE", StringComparison.OrdinalIgnoreCase)) return 1;  // Xetra
            if (symbol.EndsWith(".F", StringComparison.OrdinalIgnoreCase)) return 2;   // Frankfurt
            if (symbol.EndsWith(".STU", StringComparison.OrdinalIgnoreCase)) return 3; // Stuttgart
            if (symbol.EndsWith(".SG", StringComparison.OrdinalIgnoreCase)) return 4;  // Stuttgart (alt)
            if (symbol.EndsWith(".HM", StringComparison.OrdinalIgnoreCase)) return 5;  // Hamburg
            if (!symbol.Contains('.')) return 6;                                       // US Primary
        }
        else
        {
            if (!symbol.Contains('.')) return 1;                                       // US Primary (NASDAQ, NYSE)
            if (symbol.EndsWith(".DE", StringComparison.OrdinalIgnoreCase)) return 2;  // Xetra
            if (symbol.EndsWith(".F", StringComparison.OrdinalIgnoreCase)) return 3;   // Frankfurt
            if (symbol.EndsWith(".L", StringComparison.OrdinalIgnoreCase)) return 4;   // London
            if (symbol.EndsWith(".PA", StringComparison.OrdinalIgnoreCase)) return 5;  // Paris
        }

        return 10;
    }
}