frontend/lib/norm-utils.ts

export interface NormEntry {
    id: number;
    division_factor: string;
    sub_type: string;
    composition: string;
    count_range: string;
    route: string;
    rules: {
        upto_3000m: string;
        above_3000m: string;
    };
    tolerance_adjustments: {
        tolerance_3_percent: string;
        tolerance_5_7_percent: string;
        tolerance_10_percent: string;
        tolerance_plus0_minus3_5: string;
        tolerance_1_2_percent: string;
    };
}

export interface ToleranceOption {
    key: keyof NormEntry["tolerance_adjustments"];
    label: string;
}

export const TOLERANCE_OPTIONS: ToleranceOption[] = [
    { key: "tolerance_1_2_percent", label: "+/- 1% or +/- 2%" },
    { key: "tolerance_3_percent", label: "+/- 3%" },
    { key: "tolerance_5_7_percent", label: "+/- 5%, 6% or 7%" },
    { key: "tolerance_10_percent", label: "+/- 10%" },
    { key: "tolerance_plus0_minus3_5", label: "+0/-3% or +0/-5%" },
];

export interface CalculationResult {
    applicableRule: string;
    ruleDescription: string;
    baseReservation: number;
    toleranceAdjustment: string;
    adjustedPercentage: number;
    finalReservation: number;
    orderQty: number;
}

interface ParsedRule {
    percentage: number;
    fixedMeters: number;
}

interface ToleranceAdjustment {
    adjustmentPercent: number;
    isLess: boolean;
    label: string;
}

export function parseRuleString(ruleString: string): ParsedRule {
    let percentage = 0;
    let fixedMeters = 0;
    const pattern = /(\d+(?:\.\d+)?)\s*%\s*or\s*(\d+(?:\.\d+)?)\s*m/i;
    const match = ruleString.match(pattern);
    if (match) {
        percentage = parseFloat(match[1]);
        fixedMeters = parseFloat(match[2]);
    }
    return { percentage, fixedMeters };
}

export function parseToleranceAdjustment(toleranceString: string): ToleranceAdjustment {
    if (toleranceString.toLowerCase().includes("std norms") || toleranceString.toLowerCase().includes("standard")) {
        return { adjustmentPercent: 0, isLess: false, label: "As per Std Norms" };
    }
    const extraPattern = /(\d+(?:\.\d+)?)\s*%\s*extra/i;
    const lessPattern = /-?\s*(\d+(?:\.\d+)?)\s*%\s*less/i;

    const extraMatch = toleranceString.match(extraPattern);
    if (extraMatch) return { adjustmentPercent: parseFloat(extraMatch[1]), isLess: false, label: `+${extraMatch[1]}% Extra` };

    const lessMatch = toleranceString.match(lessPattern);
    if (lessMatch) return { adjustmentPercent: parseFloat(lessMatch[1]), isLess: true, label: `-${lessMatch[1]}% Less` };

    return { adjustmentPercent: 0, isLess: false, label: toleranceString };
}

export function calculateBaseReservation(orderQty: number, percentage: number, fixedMeters: number): number {
    const percentageReservation = orderQty * (percentage / 100);
    return Math.max(percentageReservation, fixedMeters);
}

export function calculateFinalReservation(orderQty: number, ruleString: string, toleranceString: string): CalculationResult {
    const { percentage, fixedMeters } = parseRuleString(ruleString);
    const tolerance = parseToleranceAdjustment(toleranceString);

    const baseReservation = calculateBaseReservation(orderQty, percentage, fixedMeters);

    let adjustedPercentage = percentage;
    if (tolerance.isLess) {
        adjustedPercentage = Math.max(0, percentage - tolerance.adjustmentPercent);
    } else {
        adjustedPercentage = percentage + tolerance.adjustmentPercent;
    }

    const finalReservation = calculateBaseReservation(orderQty, adjustedPercentage, fixedMeters);

    const ruleDescription = orderQty <= 3000 ? `Upto 3000m: ${ruleString}` : `Above 3000m: ${ruleString}`;

    return {
        applicableRule: ruleString,
        ruleDescription,
        baseReservation: Math.round(baseReservation * 100) / 100,
        toleranceAdjustment: tolerance.label,
        adjustedPercentage,
        finalReservation: Math.round(finalReservation * 100) / 100,
        orderQty
    };
}

// Grouping functions
export function getUniqueDivisionFactors(data: NormEntry[]): string[] {
    return [...new Set(data.map(item => item.division_factor))].sort();
}

export function getSubTypesByDivision(data: NormEntry[], division: string): string[] {
    return [...new Set(data.filter(item => item.division_factor === division).map(item => item.sub_type))].sort();
}

export function getCompositionsByDivisionAndSubType(data: NormEntry[], division: string, subType: string): string[] {
    return [...new Set(data.filter(item => item.division_factor === division && item.sub_type === subType).map(item => item.composition))].sort();
}

export function getCountRangesByComposition(data: NormEntry[], division: string, subType: string, composition: string): string[] {
    return [...new Set(data.filter(item => item.division_factor === division && item.sub_type === subType && item.composition === composition).map(item => item.count_range))].sort();
}

export function findNormEntry(data: NormEntry[], division: string, subType: string, composition: string, countRange: string): NormEntry | undefined {
    return data.find(item => item.division_factor === division && item.sub_type === subType && item.composition === composition && item.count_range === countRange);
}