import type { Response } from 'express';

import { Prisma } from '@prisma/client';

export type QueryValue = unknown;

export function getSingle(value: QueryValue): string | undefined {
  if (Array.isArray(value)) {
    const first = value[0];
    return typeof first === 'string' ? first : first === undefined || first === null ? undefined : String(first);
  }

  if (typeof value === 'string') {
    return value;
  }

  if (value === undefined || value === null) {
    return undefined;
  }

  return String(value);
}

export function getFirst(value: QueryValue): string | undefined {
  return getSingle(value);
}

export function getStringArray(value: QueryValue): string[] {
  if (Array.isArray(value)) {
    return value
      .filter((item) => item !== undefined && item !== null && item !== '')
      .map((item) => String(item));
  }

  if (value === undefined || value === null || value === '') {
    return [];
  }

  return [String(value)];
}

export function toArray(value: QueryValue): string[] {
  return getStringArray(value);
}

export function parseRange(query: Record<string, QueryValue>): { start: number; end: number; take: number } {
  const start = Number(getFirst(query._start) ?? 0);
  const end = Number(getFirst(query._end) ?? start + 25);
  const safeStart = Number.isFinite(start) && start >= 0 ? start : 0;
  const safeEnd = Number.isFinite(end) && end > safeStart ? end : safeStart + 25;

  return {
    start: safeStart,
    end: safeEnd,
    take: safeEnd - safeStart,
  };
}

export function toSortOrder(value: string | undefined): 'asc' | 'desc' {
  return String(value ?? 'ASC').toLowerCase() === 'desc' ? 'desc' : 'asc';
}

export function containsInsensitive(value: string) {
  return {
    contains: value,
    mode: 'insensitive' as const,
  };
}

export function toNumberValue(value: unknown): number | null | undefined {
  if (value === undefined) return undefined;
  if (value === null || value === '') return null;
  const numeric = Number(value);
  return Number.isNaN(numeric) ? undefined : numeric;
}

export function toDateValue(value: unknown): Date | null | undefined {
  if (value === undefined) return undefined;
  if (value === null || value === '') return null;
  return new Date(String(value));
}

export function toDecimalValue(value: unknown): Prisma.Decimal | null | undefined {
  if (value === undefined) return undefined;
  if (value === null || value === '') return null;
  return new Prisma.Decimal(String(value));
}

export function setListHeaders(
  response: Response,
  totalOrResource: number | string,
  start: number,
  end: number,
  resourceOrTotal: string | number,
): void {
  const total = typeof totalOrResource === 'number' ? totalOrResource : Number(resourceOrTotal);
  const resource = typeof totalOrResource === 'string' ? totalOrResource : String(resourceOrTotal);
  const safeStart = Number.isFinite(start) ? start : 0;
  const safeEnd = Number.isFinite(end) ? end : safeStart;
  const contentEnd = total === 0 ? safeStart : Math.min(Math.max(safeEnd - 1, safeStart), Math.max(total - 1, safeStart));
  response.setHeader('Content-Range', `${resource} ${safeStart}-${contentEnd}/${total}`);
  response.setHeader('Access-Control-Expose-Headers', 'Content-Range');
}