import type { WeekdayName } from './field-purpose';
import { isWeekdayName } from './field-purpose';

export type WeekdayTemplateInput = {
  readonly startBranchId: string;
  readonly endBranchId: string;
  readonly customerIds: readonly string[];
};

export type WeekdaysInput = Partial<Record<WeekdayName, WeekdayTemplateInput>>;

export function isValidCycleNumber(raw: number): boolean {
  return Number.isInteger(raw) && raw >= 1;
}

export function assertCompleteWeekday(
  raw: WeekdayTemplateInput | undefined,
): WeekdayTemplateInput | undefined {
  if (raw === undefined) {
    return undefined;
  }
  if (
    !raw.startBranchId ||
    !raw.endBranchId ||
    !Array.isArray(raw.customerIds) ||
    raw.customerIds.length === 0
  ) {
    throw new Error('incomplete');
  }
  return raw;
}

export function parseWeekdaysInput(raw: unknown): WeekdaysInput {
  if (raw === undefined || raw === null) {
    return {};
  }
  if (typeof raw !== 'object' || Array.isArray(raw)) {
    throw new Error('incomplete');
  }
  const record = raw as Record<string, WeekdayTemplateInput>;
  const result: WeekdaysInput = {};
  for (const [key, value] of Object.entries(record)) {
    if (!isWeekdayName(key)) {
      throw new Error('incomplete');
    }
    const complete = assertCompleteWeekday(value);
    if (complete) {
      result[key] = complete;
    }
  }
  return result;
}

/** RFC 4180-style record split that preserves commas inside quotes. */
export function parseCsvRecord(line: string): string[] {
  const cells: string[] = [];
  let current = '';
  let inQuotes = false;
  for (let i = 0; i < line.length; i++) {
    const ch = line[i];
    if (inQuotes) {
      if (ch === '"') {
        if (line[i + 1] === '"') {
          current += '"';
          i += 1;
        } else {
          inQuotes = false;
        }
      } else {
        current += ch;
      }
    } else if (ch === '"') {
      inQuotes = true;
    } else if (ch === ',') {
      cells.push(current.trim());
      current = '';
    } else {
      current += ch;
    }
  }
  cells.push(current.trim());
  return cells;
}

export function isAllowedCsvUpload(file: {
  mimetype: string;
  originalname: string;
}): boolean {
  return (
    file.mimetype.includes('csv') ||
    file.originalname.toLowerCase().endsWith('.csv')
  );
}