import type {
  CampaignPack,
  CustomWorldProfile,
} from '../../types';

export interface ContentDiffReport {
  summary: string;
  changedFields: string[];
}

export function buildContentDiffReport(params: {
  previousProfile: CustomWorldProfile | null | undefined;
  nextProfile: CustomWorldProfile | null | undefined;
  previousCampaignPack?: CampaignPack | null;
  nextCampaignPack?: CampaignPack | null;
}) {
  const changedFields: string[] = [];
  if (params.previousProfile?.summary !== params.nextProfile?.summary) changedFields.push('profile.summary');
  if (params.previousProfile?.scenarioPackId !== params.nextProfile?.scenarioPackId) changedFields.push('profile.scenarioPackId');
  if (params.previousProfile?.campaignPackId !== params.nextProfile?.campaignPackId) changedFields.push('profile.campaignPackId');
  if (params.previousCampaignPack?.authoringStyle !== params.nextCampaignPack?.authoringStyle) {
    changedFields.push('campaignPack.authoringStyle');
  }
  if (params.previousCampaignPack?.actTemplates.length !== params.nextCampaignPack?.actTemplates.length) {
    changedFields.push('campaignPack.actTemplates');
  }

  return {
    summary:
      changedFields.length > 0
        ? `当前版本相较上个版本改动了 ${changedFields.length} 个关键 narrative 字段。`
        : '当前版本与上个版本相比没有明显 narrative 结构差异。',
    changedFields,
  } satisfies ContentDiffReport;
}