#pragma once
#include "core/result/Result.h"
#include "datahub/Producer.h"

#include <QJsonArray>
#include <QJsonObject>
#include <QObject>
#include <QTimer>
#include <QVector>

#include <functional>

namespace fincept::services {

struct QuoteData {
    QString symbol;
    QString name;
    double price = 0;
    double change = 0;
    double change_pct = 0;
    double high = 0;
    double low = 0;
    double volume = 0;
};

struct InfoData {
    QString symbol;
    QString name;
    QString sector;
    QString industry;
    QString country;
    QString currency;
    double market_cap = 0;
    double pe_ratio = 0;
    double forward_pe = 0;
    double price_to_book = 0;
    double dividend_yield = 0;
    double beta = 0;
    double week52_high = 0;
    double week52_low = 0;
    double avg_volume = 0;
    double eps = 0; // revenuePerShare as proxy
    double roe = 0;
    double profit_margin = 0;
    double debt_to_equity = 0;
    double current_ratio = 0;
};

struct HistoryPoint {
    qint64 timestamp = 0; // seconds since epoch
    double open = 0;
    double high = 0;
    double low = 0;
    double close = 0;
    qint64 volume = 0;
};

struct TickerDef {
    QString symbol;
    QString name;
};

struct MarketCategory {
    QString category;
    QStringList tickers;
};

struct RegionalMarket {
    QString region;
    QVector<TickerDef> tickers;
};

/// Fetches market quotes via Python/yfinance.
/// Features:
///   - Request batching: collects symbols over a 100ms window, deduplicates, single Python call
///   - Quote caching: returns cached data immediately, refreshes in background
///   - DataHub producer: owns the `market:quote:*` topic family. Phase 2 —
///     see fincept-qt/docs/datahub-phases/phase-02-market-data-pilot.md.
class MarketDataService : public QObject, public fincept::datahub::Producer {
    Q_OBJECT
  public:
    using QuoteCallback = std::function<void(bool, QVector<QuoteData>)>;

    static MarketDataService& instance();

    /// Register this service as a DataHub producer + install the default
    /// `market:quote:*` policy. Idempotent — safe if called more than once.
    /// Called from main.cpp after `datahub::register_metatypes()`.
    void ensure_registered_with_hub();

    // ── fincept::datahub::Producer ────────────────────────────────────────
    QStringList topic_patterns() const override;
    void refresh(const QStringList& topics) override;
    int max_requests_per_sec() const override;

    /// Fetch quotes — batched and cached. Callback receives filtered results for requested symbols.
    /// Phase 3+: prefer `DataHub::subscribe(this, "market:quote:<sym>", ...)` for streaming widgets.
    /// This callback API remains for one-shot reads (e.g. report builder snapshots).
    void fetch_quotes(const QStringList& symbols, QuoteCallback cb);

    using NewsCallback = std::function<void(bool, QJsonArray)>;
    void fetch_news(const QString& symbol, int count, NewsCallback cb);

    /// Fetch full company info (P/E, 52W range, market cap, ratios, etc.)
    using InfoCallback = std::function<void(bool, InfoData)>;
    void fetch_info(const QString& symbol, InfoCallback cb);

    /// Fetch historical OHLCV data. period: "1mo","3mo","6mo","1y","2y","5y"
    /// interval: "1d","1wk","1mo"
    /// Phase 3+: prefer `DataHub::subscribe(this, "market:history:<sym>:<period>:<interval>", ...)`
    /// for streaming chart widgets. Callback API remains for one-shot reads.
    using HistoryCallback = std::function<void(bool, QVector<HistoryPoint>)>;
    void fetch_history(const QString& symbol, const QString& period, const QString& interval, HistoryCallback cb);

    /// Fetch 5-day hourly sparkline data for multiple symbols in one Python call.
    /// Callback: map of symbol -> list of close prices (chronological).
    /// Phase 3+: prefer `DataHub::subscribe(this, "market:sparkline:<sym>", ...)` for live tables.
    using SparklineCallback = std::function<void(bool, QHash<QString, QVector<double>>)>;
    void fetch_sparklines(const QStringList& symbols, SparklineCallback cb);

    /// Resolve human-readable display names (e.g. "^GSPC" → "S&P 500",
    /// "GC=F" → "Gold") for cryptic tickers so market tables can show names
    /// instead of raw symbols. Names come from yfinance (longName/shortName).
    ///
    /// Names are static, so they are cached to disk: the callback fires once
    /// immediately with whatever is already cached for `symbols`, and — if any
    /// were missing — again after a single `quote_names` Python call resolves
    /// and persists them. The network hit is paid once per symbol, never on
    /// the quote-refresh path.
    using NamesCallback = std::function<void(const QHash<QString, QString>&)>;
    void resolve_names(const QStringList& symbols, NamesCallback cb);

    /// Currency-symbol prefix for a symbol's price (e.g. "AAPL" → "$",
    /// "RELIANCE.NS" → "₹"), or an empty string when unknown or not meaningful
    /// (forex pairs, index levels/yields). Resolved alongside display names by
    /// `resolve_names` and read from the same disk-backed cache, so this is a
    /// cheap synchronous lookup.
    QString currency_prefix(const QString& symbol);

    static QVector<MarketCategory> default_global_markets();
    static QVector<RegionalMarket> default_regional_markets();

    /// Default symbol lists for dashboard widgets
    static QStringList indices_symbols();
    static QStringList forex_symbols();
    static QStringList crypto_symbols();
    static QStringList commodity_symbols();
    static QStringList mover_symbols();
    static QStringList global_snapshot_symbols();

  private:
    MarketDataService();
    void flush_batch();

    /// Internal: publish the per-symbol result to the hub and clear
    /// in_flight for the matching topic. Called from inside `flush_batch`.
    void publish_quote_to_hub(const QuoteData& q);
    void publish_history_to_hub(const QString& symbol, const QString& period, const QString& interval,
                                const QVector<HistoryPoint>& points);
    void publish_sparkline_to_hub(const QString& symbol, const QVector<double>& points);

    // ── Display-name cache (symbol → human-readable name) ──
    // Persisted to SettingsRepository so resolution survives restarts and the
    // per-symbol yfinance .info cost is paid at most once.
    void load_name_cache();
    void persist_name_cache();
    QHash<QString, QString> name_cache_;
    QHash<QString, QString> currency_cache_; // symbol → ISO currency code (e.g. "USD")
    bool name_cache_loaded_ = false;

    // ── Batching ──
    struct PendingRequest {
        QStringList symbols;
        QuoteCallback cb;
    };
    QVector<PendingRequest> pending_;
    bool batch_scheduled_ = false;

    bool hub_registered_ = false;

    // ── Caching — delegated to CacheManager ──
    static constexpr int kQuoteCacheTtlSec = 30;
};

} // namespace fincept::services