/*
 * Report and image-rules validation. These are pure functions with no DOM or
 * state dependencies so they can be tested independently and kept in sync with
 * server-side validation in src/routes/configRoutes.js (A7).
 */

/* ── Report validation ──────────────────────────────────────────────────── */

/*
 * Returns an array of human-readable issue strings. The caller decides whether
 * issues are informational or blocking.
 */
export function validateReport(report, template, attachments) {
  const issues = [];

  for (const section of template.definition.sections || []) {
    for (const field of section.fields || []) {
      const value = report.answers[field.id];
      const required = Boolean(field.required || evaluateRequiredWhen(field.requiredWhen, report.answers));

      if (field.type === 'attachment') {
        const fieldAttachments = attachments.filter((item) => item.fieldId === field.id);

        if (required && fieldAttachments.length === 0) {
          issues.push(`${field.label}: at least one image is required.`);
        }

        continue;
      }

      if (required && isBlankValue(value, field.type)) {
        issues.push(`${field.label}: value is required.`);
      }

      if (field.type === 'number' && value !== '' && value != null) {
        if (Number.isNaN(Number(value))) {
          issues.push(`${field.label}: number is invalid.`);
        }

        if (field.validation?.min !== undefined && Number(value) < field.validation.min) {
          issues.push(`${field.label}: must be at least ${field.validation.min}.`);
        }
      }
    }
  }

  return issues;
}

/* ── Image-rules validation (mirrors server-side logic in configRoutes) ── */

export function validateImageRulesPayload(payload) {
  if (!payload.name) {
    return 'Policy name is required';
  }

  if (!payload.allowedMimeTypes.length) {
    return 'Add at least one MIME type';
  }

  if (!Number.isFinite(payload.maxFileSizeBytes) || payload.maxFileSizeBytes <= 0) {
    return 'Max file size must be greater than 0';
  }

  if (!Number.isInteger(payload.maxWidthPx) || payload.maxWidthPx <= 0) {
    return 'Max width must be a positive number';
  }

  if (!Number.isInteger(payload.maxHeightPx) || payload.maxHeightPx <= 0) {
    return 'Max height must be a positive number';
  }

  if (!Number.isInteger(payload.jpegQuality) || payload.jpegQuality < 1 || payload.jpegQuality > 100) {
    return 'JPEG quality must be between 1 and 100';
  }

  if (!Number.isInteger(payload.maxAttachmentsPerField) || payload.maxAttachmentsPerField <= 0) {
    return 'Max attachments must be a positive number';
  }

  return null;
}

/* ── Helpers ────────────────────────────────────────────────────────────── */

export function evaluateRequiredWhen(requiredWhen, answers) {
  if (!requiredWhen?.field) {
    return false;
  }

  return answers[requiredWhen.field] === requiredWhen.equals;
}

export function isBlankValue(value, type) {
  if (type === 'checkbox') {
    return false;
  }

  return value === '' || value == null;
}