import { invoke } from "@tauri-apps/api/core";

export type WallpaperState = {
  imageCount: number;
  enabled: boolean;
  intervalMinutes: number;
  shuffle: boolean;
  lockScreenOnly: boolean;
  allowMobileData: boolean;
  prefetchImmich: boolean;
  currentIndex: number;
  currentId: string | null;
  imageIds: string[];
  imageUrls: string[];
};

export type GalleryImage = {
  id: string;
  url: string;
  selected: boolean;
  cropMode: "cover" | "contain";
  cropZoom: number;
  cropPositionX: number;
  cropPositionY: number;
  cropRotation: number;
};

export type GalleryPage = {
  total: number;
  items: GalleryImage[];
};

export type ImmichConnection = {
  configured: boolean;
  serverUrl: string;
  userName: string;
};

export type ImmichAlbum = {
  id: string;
  name: string;
  assetCount: number;
  thumbnailUrl: string;
};

export type ImmichAsset = {
  id: string;
  fileName: string;
  thumbnailUrl: string;
  takenAt: string;
};

export type ImmichAssetsPage = {
  items: ImmichAsset[];
  page: number;
  hasMore: boolean;
};

export type ImmichImportProgress = {
  active: boolean;
  completed: number;
  total: number;
  bytesDownloaded: number;
  bytesTotal: number;
};

const demoState: WallpaperState = {
  imageCount: 3,
  enabled: true,
  intervalMinutes: 30,
  shuffle: true,
  lockScreenOnly: true,
  allowMobileData: false,
  prefetchImmich: true,
  currentIndex: 0,
  currentId: "demo-0",
  imageIds: ["demo-0", "demo-1", "demo-2"],
  imageUrls: ["/wallpapers/alpine.png", "/wallpapers/waterfall.png", "/wallpapers/coast.png"],
};

const inTauri = () => "__TAURI_INTERNALS__" in window;
const demoCrops = new Map<string, Pick<GalleryImage, "cropMode" | "cropZoom" | "cropPositionX" | "cropPositionY" | "cropRotation">>();
const defaultCrop = { cropMode: "cover" as const, cropZoom: 1, cropPositionX: 0.5, cropPositionY: 0.5, cropRotation: 0 };
let demoImmichConnection: ImmichConnection = { configured: false, serverUrl: "", userName: "" };

export async function getState(): Promise<WallpaperState> {
  return inTauri() ? invoke<WallpaperState>("plugin:wallpaper|get_state") : demoState;
}

export async function getGallery(offset = 0, limit = 48): Promise<GalleryPage> {
  if (inTauri()) return invoke<GalleryPage>("plugin:wallpaper|get_gallery", { offset, limit });
  return {
    total: demoState.imageUrls.length,
    items: demoState.imageUrls.slice(offset, offset + limit).map((url, index) => {
      const id = `demo-${offset + index}`;
      return { id, url, selected: offset + index === demoState.currentIndex, ...(demoCrops.get(id) ?? defaultCrop) };
    }),
  };
}

export async function selectImages(): Promise<WallpaperState> {
  if (!inTauri()) return demoState;
  return invoke<WallpaperState>("plugin:wallpaper|select_images");
}

export async function deleteImage(id: string): Promise<WallpaperState> {
  if (inTauri()) return invoke<WallpaperState>("plugin:wallpaper|delete_image", { id });
  const index = Number(id.replace("demo-", ""));
  if (Number.isInteger(index) && index >= 0 && index < demoState.imageUrls.length) {
    demoState.imageUrls.splice(index, 1);
    demoState.imageCount = demoState.imageUrls.length;
    demoState.currentIndex = Math.min(demoState.currentIndex, Math.max(0, demoState.imageCount - 1));
    demoState.imageIds = demoState.imageUrls.map((_, itemIndex) => `demo-${itemIndex}`);
    demoState.currentId = demoState.imageIds[demoState.currentIndex] ?? null;
  }
  return { ...demoState, imageUrls: [...demoState.imageUrls] };
}

export async function getImageIds(): Promise<string[]> {
  if (inTauri()) return invoke<string[]>("plugin:wallpaper|get_image_ids");
  return demoState.imageUrls.map((_, index) => `demo-${index}`);
}

export async function deleteImages(ids: string[]): Promise<WallpaperState> {
  if (inTauri()) return invoke<WallpaperState>("plugin:wallpaper|delete_images", { ids });
  const indexes = new Set(ids.map(id => Number(id.replace("demo-", ""))).filter(Number.isInteger));
  demoState.imageUrls = demoState.imageUrls.filter((_, index) => !indexes.has(index));
  demoState.imageCount = demoState.imageUrls.length;
  demoState.currentIndex = Math.min(demoState.currentIndex, Math.max(0, demoState.imageCount - 1));
  demoState.imageIds = demoState.imageUrls.map((_, index) => `demo-${index}`);
  demoState.currentId = demoState.imageIds[demoState.currentIndex] ?? null;
  return { ...demoState, imageUrls: [...demoState.imageUrls] };
}

export async function setImageCrop(image: GalleryImage): Promise<GalleryImage> {
  const payload = {
    id: image.id,
    mode: image.cropMode,
    zoom: image.cropZoom,
    positionX: image.cropPositionX,
    positionY: image.cropPositionY,
    rotation: image.cropRotation,
  };
  if (inTauri()) return invoke<GalleryImage>("plugin:wallpaper|set_image_crop", payload);
  demoCrops.set(image.id, {
    cropMode: image.cropMode,
    cropZoom: image.cropZoom,
    cropPositionX: image.cropPositionX,
    cropPositionY: image.cropPositionY,
    cropRotation: image.cropRotation,
  });
  return { ...image };
}

export async function setSetting(name: "shuffle" | "lockScreenOnly" | "allowMobileData" | "prefetchImmich", value: boolean) {
  if (!inTauri()) return { ...demoState, [name]: value };
  return invoke<WallpaperState>("plugin:wallpaper|set_setting", { name, value });
}

export async function setIntervalMinutes(value: number) {
  if (!inTauri()) {
    demoState.intervalMinutes = value;
    demoState.enabled = value > 0;
    return { ...demoState };
  }
  return invoke<WallpaperState>("plugin:wallpaper|set_interval", { minutes: value });
}

export async function nextWallpaper(): Promise<WallpaperState> {
  if (!inTauri()) {
    if (demoState.imageUrls.length) demoState.currentIndex = (demoState.currentIndex + 1) % demoState.imageUrls.length;
    demoState.currentId = demoState.imageIds[demoState.currentIndex] ?? null;
    return { ...demoState };
  }
  return invoke<WallpaperState>("plugin:wallpaper|next_wallpaper");
}

export async function applyWallpaper(id: string): Promise<WallpaperState> {
  if (!inTauri()) {
    const index = demoState.imageIds.indexOf(id);
    if (index < 0) throw new Error("Image not found");
    demoState.currentIndex = index;
    demoState.currentId = id;
    return { ...demoState };
  }
  return invoke<WallpaperState>("plugin:wallpaper|apply_wallpaper", { id });
}

export async function getImmichConnection(): Promise<ImmichConnection> {
  return inTauri() ? invoke<ImmichConnection>("plugin:wallpaper|get_immich_connection") : demoImmichConnection;
}

export async function connectImmich(serverUrl: string, apiKey: string): Promise<ImmichConnection> {
  if (inTauri()) return invoke<ImmichConnection>("plugin:wallpaper|connect_immich", { serverUrl, apiKey });
  if (!serverUrl.trim() || !apiKey.trim()) throw new Error("Missing Immich credentials");
  demoImmichConnection = { configured: true, serverUrl: serverUrl.trim(), userName: "Demo User" };
  return demoImmichConnection;
}

export async function disconnectImmich(): Promise<ImmichConnection> {
  if (inTauri()) return invoke<ImmichConnection>("plugin:wallpaper|disconnect_immich");
  demoImmichConnection = { configured: false, serverUrl: "", userName: "" };
  return demoImmichConnection;
}

export async function getImmichAlbums(): Promise<ImmichAlbum[]> {
  if (inTauri()) return (await invoke<{ albums: ImmichAlbum[] }>("plugin:wallpaper|get_immich_albums")).albums;
  return [{ id: "demo-album", name: "Nature", assetCount: 3, thumbnailUrl: "/wallpapers/alpine.png" }];
}

export async function getImmichAssets(albumId: string | null, page = 1, size = 30): Promise<ImmichAssetsPage> {
  if (inTauri()) return invoke<ImmichAssetsPage>("plugin:wallpaper|get_immich_assets", { albumId, page, size });
  return {
    items: demoState.imageUrls.map((thumbnailUrl, index) => ({
      id: `00000000-0000-4000-8000-00000000000${index}`,
      fileName: `wallpaper-${index + 1}.jpg`,
      thumbnailUrl,
      takenAt: "2026-08-21T12:00:00Z",
    })),
    page,
    hasMore: false,
  };
}

export async function importImmichAssets(ids: string[]): Promise<WallpaperState> {
  if (inTauri()) return invoke<WallpaperState>("plugin:wallpaper|import_immich_assets", { ids });
  return { ...demoState, imageUrls: [...demoState.imageUrls] };
}

export async function getImmichImportProgress(): Promise<ImmichImportProgress> {
  if (inTauri()) return invoke<ImmichImportProgress>("plugin:wallpaper|get_immich_import_progress");
  return { active: false, completed: 0, total: 0, bytesDownloaded: 0, bytesTotal: 0 };
}