import {
  resolveCustomWorldCampSceneImage,
  resolveCustomWorldLandmarkImageMap,
} from '../data/customWorldVisuals';
import type {
  CustomWorldLandmark,
  CustomWorldProfile,
  SceneChapterBlueprint,
} from '../types';
import { resolveCustomWorldCampScene } from './customWorldCamp';

export type CustomWorldSceneKind = 'camp' | 'landmark';

export type CustomWorldSceneActImagePreview = {
  id: string;
  title: string;
  imageSrc: string;
};

export type CustomWorldScenePresentation = {
  id: string;
  kind: CustomWorldSceneKind;
  name: string;
  description: string;
  imageSrc: string;
  sceneChapters: SceneChapterBlueprint[];
  actPreviews: CustomWorldSceneActImagePreview[];
};

function normalizeText(value: string | null | undefined) {
  return value?.trim() ?? '';
}

export function resolveScenePresentationChapters(params: {
  sceneChapters: CustomWorldProfile['sceneChapterBlueprints'];
  sceneId: string;
  sceneName: string;
}) {
  const sceneChapters = params.sceneChapters ?? [];
  const normalizedSceneId = params.sceneId.trim();
  const normalizedSceneName = params.sceneName.trim();

  const directMatches = sceneChapters.filter(
    (chapter) => chapter.sceneId.trim() === normalizedSceneId,
  );
  if (directMatches.length > 0) {
    return directMatches;
  }

  const linkedMatches = sceneChapters.filter((chapter) =>
    chapter.linkedLandmarkIds.some(
      (landmarkId) => landmarkId.trim() === normalizedSceneId,
    ),
  );
  if (linkedMatches.length > 0) {
    return linkedMatches;
  }

  return sceneChapters.filter((chapter) => {
    const chapterTitle = chapter.title.trim();
    return (
      chapterTitle === normalizedSceneName ||
      chapter.summary.includes(normalizedSceneName) ||
      chapter.acts.some(
        (act) =>
          act.title.includes(normalizedSceneName) ||
          act.summary.includes(normalizedSceneName),
      )
    );
  });
}

export function resolveScenePresentationImage(params: {
  sceneImageSrc?: string | null;
  sceneChapters: SceneChapterBlueprint[];
}) {
  const firstActImageSrc =
    params.sceneChapters
      .flatMap((chapter) => chapter.acts)
      .map((act) => normalizeText(act.backgroundImageSrc))
      .find(Boolean) || '';

  return firstActImageSrc || normalizeText(params.sceneImageSrc);
}

export function collectSceneActImagePreviews(params: {
  sceneChapters: SceneChapterBlueprint[];
  sceneImageSrc?: string | null;
}) {
  const sceneImageSrc = normalizeText(params.sceneImageSrc);
  const actPreviews = params.sceneChapters.flatMap((chapter) =>
    chapter.acts
      .map((act, index) => {
        // 中文注释：幕预览图片必须优先读取当前幕背景；场景图只给缺图的旧数据兜底，避免开局场景和普通场景在列表、详情里显示不同图片。
        const imageSrc = normalizeText(act.backgroundImageSrc) || sceneImageSrc;
        return {
          id: act.id.trim() || `${chapter.id}-act-${index}`,
          title: act.title.trim() || `第${index + 1}幕`,
          imageSrc,
        };
      })
      .filter((act) => act.imageSrc),
  );

  if (actPreviews.length > 0 || !sceneImageSrc) {
    return actPreviews;
  }

  return [1, 2, 3].map((actNumber) => ({
    id: `fallback-scene-act-${actNumber}`,
    title: `第${actNumber}幕`,
    imageSrc: sceneImageSrc,
  }));
}

export function buildScenePresentation(params: {
  profile: CustomWorldProfile;
  scene: CustomWorldLandmark;
  kind: CustomWorldSceneKind;
  sceneImageSrc?: string | null;
}) {
  const sceneChapters = resolveScenePresentationChapters({
    sceneChapters: params.profile.sceneChapterBlueprints,
    sceneId: params.scene.id,
    sceneName: params.scene.name,
  });
  const imageSrc = resolveScenePresentationImage({
    sceneImageSrc: params.sceneImageSrc ?? params.scene.imageSrc,
    sceneChapters,
  });

  return {
    id: params.scene.id,
    kind: params.kind,
    name: params.scene.name,
    description: params.scene.description,
    imageSrc,
    sceneChapters,
    actPreviews: collectSceneActImagePreviews({
      sceneChapters,
      sceneImageSrc: imageSrc,
    }),
  } satisfies CustomWorldScenePresentation;
}

export function buildCustomWorldScenePresentations(profile: CustomWorldProfile) {
  const landmarkImageById = resolveCustomWorldLandmarkImageMap(profile);
  const campScene = resolveCustomWorldCampScene(profile);
  const campPresentation = buildScenePresentation({
    profile,
    scene: campScene,
    kind: 'camp',
    sceneImageSrc: resolveCustomWorldCampSceneImage(profile),
  });
  const landmarkPresentations = profile.landmarks.map((landmark) =>
    buildScenePresentation({
      profile,
      scene: landmark,
      kind: 'landmark',
      sceneImageSrc: landmarkImageById.get(landmark.id) || landmark.imageSrc,
    }),
  );

  return {
    camp: campPresentation,
    landmarks: landmarkPresentations,
  };
}