/**
 * Resolve the effective profit target and consistency for an account based on its withdrawal strategy.
 *
 * Mode A (targetSameEquity=true): the account must reach the same cumulative equity level.
 *   remainingProfit = priorProfit + totalWithdrawals (profit still in the account after payouts)
 *   effectiveProfitTarget = profitTarget − remainingProfit
 *
 * Mode B (withdrawalStages non-empty): Stage 1 (no withdrawals yet) uses base profitTarget/consistency.
 *   After the Nth withdrawal, use withdrawalStages[N-1]; last stage repeats.
 * Fallback: returns base profitTarget and consistency unchanged.
 */
export function resolveEffectiveConfig(
    profitTarget: number,
    consistency: number,
    minTradingDays: number,
    targetSameEquity: boolean,
    withdrawalStages: { profit: number; consistency: number; minTradingDays: number }[],
    priorProfit: number,
    fundTransactions: { date: string; amount: number }[]
): { profitTarget: number; consistency: number; minTradingDays: number } {
    if (targetSameEquity) {
        // Withdrawals reduce the profit remaining in the account
        const totalWithdrawals = fundTransactions
            .filter((f) => f.amount < 0)
            .reduce((s, f) => s + f.amount, 0); // negative sum
        const remainingProfit = priorProfit + totalWithdrawals;
        return { profitTarget: Math.max(0, profitTarget - remainingProfit), consistency, minTradingDays };
    }
    if (withdrawalStages.length > 0) {
        const withdrawalCount = fundTransactions.filter((f) => f.amount < 0).length;
        if (withdrawalCount === 0) {
            return { profitTarget, consistency, minTradingDays }; // Stage 1 = base values
        }
        const idx = Math.min(withdrawalCount - 1, withdrawalStages.length - 1);
        const stage = withdrawalStages[idx];
        return { profitTarget: stage.profit, consistency: stage.consistency, minTradingDays: stage.minTradingDays };
    }
    return { profitTarget, consistency, minTradingDays };
}

/** @deprecated Use resolveEffectiveConfig instead */
export function resolveEffectiveProfitTarget(
    profitTarget: number,
    targetSameEquity: boolean,
    withdrawalStages: { profit: number; consistency: number; minTradingDays: number }[],
    priorProfit: number,
    fundTransactions: { date: string; amount: number }[]
): number {
    return resolveEffectiveConfig(profitTarget, 0, 0, targetSameEquity, withdrawalStages, priorProfit, fundTransactions).profitTarget;
}

/** Dollar-per-point value for common futures products. */
export const POINT_VALUES: { [symbol: string]: number } = {
    NQ: 20, MNQ: 2, ES: 50, MES: 5,
    YM: 5, MYM: 0.5, RTY: 50, M2K: 10,
    GC: 100, MGC: 10, SI: 50, CL: 1000,
    MCL: 100, NG: 10000, ZB: 1000, ZN: 1000,
    ZF: 1000, '6E': 125000, '6J': 12500000, '6B': 62500,
};

/**
 * Compute the next trading day's profit target for an account.
 *
 * Path 1 – No positive trading days yet:
 *   target = profitTarget × consistency
 *
 * Path 2 – At least one positive day exists:
 *   maxDay     = highest single-day P&L so far
 *   realTarget = maxDay / consistency  (the total profit at which maxDay ≤ consistency% of total)
 *   needed     = realTarget − totalProfit
 *
 *   if needed > maxDay  → target maxDay (still a long way from the real target; trade a normal day)
 *   else                → target needed (close to the real target; aim for exactly what's left)
 *
 * Min-day reservation (only when minDayPnL > 0):
 *   When there are still mandatory trading days remaining, today's target is capped so that
 *   enough profit is reserved for each future mandatory day to meet minDayPnL.
 *   Cap = (profitTarget - totalProfit) − (remainingDaysAfterToday × minDayPnL)
 *   Floor = minDayPnL (we must make at least this today)
 */
export function computeDailyTarget(
    profitTarget: number,
    consistency: number,
    totalProfit: number,
    dailyPnL: { date: string; pnl: number }[],
    minDayPnL: number = 0,      // -999 or 0 = no minimum per day
    minTradingDays: number = 0  // 0 = no minimum trading days
): { amount: number; path: 'first_day' | 'normal_day' | 'reduced_day' } {
    const qualifyingDays = minDayPnL === 0 ? dailyPnL : dailyPnL.filter((d) => d.pnl >= minDayPnL);
    const daysTraded = qualifyingDays.length;

    // --- Base target via consistency logic ---
    let baseAmount: number;
    let path: 'first_day' | 'normal_day' | 'reduced_day';

    if (daysTraded === 0) {
        // 0% or 100% consistency = no constraint; let min-day reservation drive the target
        baseAmount = (consistency === 0 || consistency >= 1) ? 0 : profitTarget * consistency;
        path = 'first_day';
    } else if (consistency === 0 || consistency >= 1) {
        // No consistency rule to satisfy — base amount is $0.
        // The min-day reservation block below handles any mandatory-day targeting.
        baseAmount = 0;
        path = 'reduced_day';
    } else if (totalProfit >= profitTarget) {
        // Profit target already met — stop solving for consistency, let min-day reservation handle remaining days
        baseAmount = 0;
        path = 'reduced_day';
    } else {
        const maxDay = Math.max(...qualifyingDays.map((d) => d.pnl));
        const realTarget = maxDay / consistency;
        const needed = realTarget - totalProfit;

        if (needed > maxDay) {
            baseAmount = maxDay;
            path = 'normal_day';
        } else {
            baseAmount = Math.max(0, needed);
            path = 'reduced_day';
        }
    }

    // --- Min-day reservation (only when minDayPnL is a positive value) ---
    const effectiveMinDay = minDayPnL > 0 ? minDayPnL : 0;

    if (effectiveMinDay > 0 && minTradingDays > daysTraded) {
        const remaining = profitTarget - totalProfit; // intentionally NOT clamped — can be negative

        if (remaining <= 0) {
            // Profit target already met but mandatory trading days not yet satisfied.
            // Trade exactly minDayPnL each remaining day.
            return { amount: effectiveMinDay, path };
        }

        const remainingMandatoryDays = minTradingDays - daysTraded; // includes today
        const futureReserve = (remainingMandatoryDays - 1) * effectiveMinDay;

        // Cap: don't take more than what's available after reserving future days
        const cappedByFuture = remaining - futureReserve;
        // Floor: must make at least minDayPnL today (or whatever is left if less)
        const floor = Math.min(effectiveMinDay, remaining);

        // Target what's needed to stay on track for profitTarget (cappedByFuture), floored at minDayPnL.
        // Consistency-based baseAmount is intentionally ignored here — profitTarget takes priority.
        const amount = Math.max(floor, cappedByFuture);
        return { amount: Math.round(amount * 100) / 100, path };
    }

    // When no consistency constraint and no min-day reservation applied, target the full remaining profit
    if (baseAmount <= 0 && (consistency === 0 || consistency >= 1)) {
        baseAmount = Math.max(0, profitTarget - totalProfit);
    }

    return { amount: Math.round(Math.max(baseAmount, effectiveMinDay) * 100) / 100, path };
}