import { type RefObject, useCallback, useEffect, useRef, useState } from 'react';

import { ApiClientError } from '../../services/apiClient';
import {
  createEditorProjectResource,
  loadEditorProject,
  loadOrCreateRecentEditorProject,
  saveEditorProjectLayout,
  type EditorProjectSnapshot,
} from '../../services/image-editor/editorProjectClient';
import {
  canvasDisplayViewportToViewport,
  type CanvasLayerResourceMetadata,
  hydrateLayer,
  serializeCanvasLayout,
  splitCanvasLayoutItems,
  viewportToCanvasDisplayViewport,
} from './ImageCanvasEditorModel';
import type {
  CanvasGenerationDialogState,
  CanvasLayer,
  CanvasViewport,
} from './ImageCanvasEditorTypes';

type ProjectResourceOptions = {
  onCreated?: (resourceId: string) => void;
  snapshotLayers?: CanvasLayer[];
};

type PendingProjectResourceLayer = {
  layer: CanvasLayer;
  options: ProjectResourceOptions;
};

type PendingProjectLayoutSave = {
  projectId: string;
  input: Parameters<typeof saveEditorProjectLayout>[1];
};

type ImageCanvasProjectPersistenceRefs = {
  layersRef: RefObject<CanvasLayer[]>;
  viewportRef: RefObject<CanvasViewport>;
  canvasGenerationDialogsRef: RefObject<CanvasGenerationDialogState[]>;
};

type ImageCanvasProjectPersistenceSetters = {
  setProjectTitle: (title: string) => void;
  setProjectRenameValue: (title: string) => void;
  setViewport: (viewport: CanvasViewport) => void;
  setLayers: (layers: CanvasLayer[]) => void;
  selectSingleLayer: (layerId: string | null) => void;
  setLayerCounter: (value: number) => void;
  restoreCanvasGenerationDialogs: (
    dialogs: CanvasGenerationDialogState[],
  ) => void;
};

function isEditorAuthError(error: unknown) {
  return (
    error instanceof ApiClientError &&
    (error.status === 401 || error.status === 403)
  );
}

function isLocalProjectResourceId(resourceId: string) {
  return resourceId.startsWith('local-');
}

function resolveProjectResourceCreateImageSrc(layer: CanvasLayer) {
  const objectKey = layer.objectKey?.trim();
  if (objectKey) {
    return `/${objectKey.replace(/^\/+/u, '')}`;
  }
  return layer.src;
}

export function useImageCanvasProjectPersistence({
  refs,
  setters,
  layers,
  canvasGenerationDialogs,
  viewport,
  canAccessProtectedData,
  openEditorLoginModal,
}: {
  refs: ImageCanvasProjectPersistenceRefs;
  setters: ImageCanvasProjectPersistenceSetters;
  layers: CanvasLayer[];
  canvasGenerationDialogs: CanvasGenerationDialogState[];
  viewport: CanvasViewport;
  canAccessProtectedData: boolean;
  openEditorLoginModal: (postLoginAction?: (() => void) | null) => void;
}) {
  const projectIdRef = useRef<string | null>(null);
  const pendingProjectResourceLayersRef = useRef<PendingProjectResourceLayer[]>(
    [],
  );
  const pendingProjectLayoutSaveRef =
    useRef<PendingProjectLayoutSave | null>(null);
  const isProjectLayoutSaveRunningRef = useRef(false);
  const saveTimerRef = useRef<number | null>(null);
  const [projectId, setProjectId] = useState<string | null>(null);
  const [isProjectReady, setIsProjectReady] = useState(false);
  const {
    setProjectTitle,
    setProjectRenameValue,
    setViewport,
    setLayers,
    selectSingleLayer,
    setLayerCounter,
    restoreCanvasGenerationDialogs,
  } = setters;

  const runPendingProjectLayoutSave = useCallback(
    function runPendingProjectLayoutSave() {
      if (isProjectLayoutSaveRunningRef.current) {
        return;
      }
      const pendingSave = pendingProjectLayoutSaveRef.current;
      if (!pendingSave) {
        return;
      }

      pendingProjectLayoutSaveRef.current = null;
      isProjectLayoutSaveRunningRef.current = true;
      Promise.resolve(
        saveEditorProjectLayout(pendingSave.projectId, pendingSave.input),
      )
        .catch((error: unknown) => {
          if (isEditorAuthError(error)) {
            openEditorLoginModal();
          }
        })
        .finally(() => {
          isProjectLayoutSaveRunningRef.current = false;
          if (
            pendingProjectLayoutSaveRef.current &&
            saveTimerRef.current === null
          ) {
            runPendingProjectLayoutSave();
          }
        });
    },
    [openEditorLoginModal],
  );

  const queueProjectLayoutSave = useCallback(
    (
      nextProjectId: string,
      input: Parameters<typeof saveEditorProjectLayout>[1],
      options: { delayMs?: number } = {},
    ) => {
      pendingProjectLayoutSaveRef.current = {
        projectId: nextProjectId,
        input,
      };
      if (saveTimerRef.current) {
        window.clearTimeout(saveTimerRef.current);
        saveTimerRef.current = null;
      }

      const delayMs = options.delayMs ?? 0;
      if (delayMs > 0) {
        saveTimerRef.current = window.setTimeout(() => {
          saveTimerRef.current = null;
          runPendingProjectLayoutSave();
        }, delayMs);
        return;
      }

      runPendingProjectLayoutSave();
    },
    [runPendingProjectLayoutSave],
  );

  const createProjectResourceForLayer = useCallback(
    (layer: CanvasLayer, options: ProjectResourceOptions = {}) => {
      const readyProjectId = projectIdRef.current;
      if (!readyProjectId) {
        pendingProjectResourceLayersRef.current.push({ layer, options });
        return;
      }
      createEditorProjectResource(readyProjectId, {
        imageSrc: resolveProjectResourceCreateImageSrc(layer),
        objectKey: layer.objectKey,
        assetObjectId: layer.assetObjectId,
        width: layer.originalWidth,
        height: layer.originalHeight,
        sourceType: layer.sourceType,
        prompt: layer.prompt,
        actualPrompt: layer.actualPrompt,
        model: layer.model,
        provider: layer.provider,
        taskId: layer.taskId,
        durationSeconds: layer.durationSeconds,
        sourceResourceId: layer.sourceResourceId,
        assetKind: layer.assetKind,
        generationInputs: layer.generationInputs,
      })
        .then((resource) => {
          options.onCreated?.(resource.resourceId);
          const layerWithResourceId = {
            ...layer,
            resourceId: resource.resourceId,
          };
          const currentLayers = refs.layersRef.current;
          const nextLayers = currentLayers.some(
            (currentLayer) => currentLayer.id === layer.id,
          )
            ? currentLayers.map((currentLayer) =>
                currentLayer.id === layer.id
                  ? layerWithResourceId
                  : currentLayer,
              )
            : options.snapshotLayers?.some(
                  (snapshotLayer) => snapshotLayer.id === layer.id,
                )
              ? options.snapshotLayers.map((snapshotLayer) =>
                  snapshotLayer.id === layer.id
                    ? layerWithResourceId
                    : snapshotLayer,
                )
              : currentLayers;
          refs.layersRef.current = nextLayers;
          setLayers(nextLayers);
          if (nextLayers.length) {
            queueProjectLayoutSave(readyProjectId, {
              viewport: viewportToCanvasDisplayViewport(refs.viewportRef.current),
              layers: serializeCanvasLayout({
                layers: nextLayers,
                canvasGenerationDialogs:
                  refs.canvasGenerationDialogsRef.current,
              }),
            });
          }
        })
        .catch((error: unknown) => {
          if (isEditorAuthError(error)) {
            openEditorLoginModal();
          }
        });
    },
    [openEditorLoginModal, queueProjectLayoutSave, refs, setLayers],
  );

  const applyProjectSnapshot = useCallback(
    (project: EditorProjectSnapshot) => {
      projectIdRef.current = project.projectId;
      setProjectId(project.projectId);
      const nextProjectTitle = project.title?.trim() || '未命名画布';
      setProjectTitle(nextProjectTitle);
      setProjectRenameValue(nextProjectTitle);
      const nextViewport = canvasDisplayViewportToViewport(project.viewport);
      setViewport(nextViewport);
      refs.viewportRef.current = nextViewport;
      const resourcesById = new Map<string, CanvasLayerResourceMetadata>(
        project.resources.map((resource) => [
          resource.resourceId,
          {
            imageSrc: resource.imageSrc,
            resourceId: resource.resourceId,
            objectKey: resource.objectKey,
            assetObjectId: resource.assetObjectId,
            width: resource.width,
            height: resource.height,
            sourceType: resource.sourceType,
            prompt: resource.prompt,
            actualPrompt: resource.actualPrompt,
            model: resource.model,
            provider: resource.provider,
            taskId: resource.taskId,
            durationSeconds: resource.durationSeconds,
            sourceResourceId: resource.sourceResourceId,
            assetKind: resource.assetKind,
            generationInputs: resource.generationInputs,
            createdAt: resource.createdAt,
            updatedAt: resource.updatedAt,
          },
        ]),
      );
      const { layerItems, generationDialogs } = splitCanvasLayoutItems(
        project.layers,
        resourcesById,
      );
      const hydratedLayers = layerItems
        .map((layer) => hydrateLayer(layer, resourcesById))
        .filter((layer): layer is CanvasLayer => Boolean(layer));
      setLayerCounter(hydratedLayers.length);
      refs.layersRef.current = hydratedLayers;
      setLayers(hydratedLayers);
      selectSingleLayer(hydratedLayers[0]?.id ?? null);
      refs.canvasGenerationDialogsRef.current = generationDialogs;
      restoreCanvasGenerationDialogs(generationDialogs);
    },
    [
      refs,
      restoreCanvasGenerationDialogs,
      selectSingleLayer,
      setLayerCounter,
      setLayers,
      setProjectRenameValue,
      setProjectTitle,
      setViewport,
    ],
  );

  const appendCanvasLayersWithResources = useCallback(
    (nextLayers: CanvasLayer[]) => {
      if (!nextLayers.length) {
        return;
      }
      const snapshotLayers = [...refs.layersRef.current, ...nextLayers];
      refs.layersRef.current = snapshotLayers;
      setLayers(snapshotLayers);
      nextLayers.forEach((layer) =>
        isLocalProjectResourceId(layer.resourceId)
          ? createProjectResourceForLayer(layer, { snapshotLayers })
          : undefined,
      );
    },
    [createProjectResourceForLayer, refs, setLayers],
  );

  useEffect(() => {
    if (!canAccessProtectedData) {
      setIsProjectReady(false);
      return undefined;
    }
    let cancelled = false;
    const projectIdFromQuery =
      typeof window === 'undefined'
        ? null
        : new URLSearchParams(window.location.search)
            .get('projectid')
            ?.trim() || null;
    const loadProject = projectIdFromQuery
      ? loadEditorProject(projectIdFromQuery)
      : loadOrCreateRecentEditorProject();

    loadProject
      .then((project) => {
        if (cancelled) {
          return;
        }
        applyProjectSnapshot(project);
        const pendingLayers = pendingProjectResourceLayersRef.current.splice(0);
        pendingLayers.forEach(({ layer, options }) => {
          createProjectResourceForLayer(layer, options);
        });
        setIsProjectReady(true);
      })
      .catch((error: unknown) => {
        if (cancelled) {
          return;
        }
        setIsProjectReady(false);
        if (isEditorAuthError(error)) {
          openEditorLoginModal(() => {
            window.location.reload();
          });
        }
      });

    return () => {
      cancelled = true;
    };
  }, [
    canAccessProtectedData,
    applyProjectSnapshot,
    createProjectResourceForLayer,
    openEditorLoginModal,
  ]);

  useEffect(() => {
    if (!projectId || !isProjectReady) {
      return undefined;
    }
    queueProjectLayoutSave(
      projectId,
      {
        viewport: viewportToCanvasDisplayViewport(viewport),
        layers: serializeCanvasLayout({
          layers,
          canvasGenerationDialogs,
        }),
      },
      { delayMs: 450 },
    );

    return () => {
      if (saveTimerRef.current) {
        window.clearTimeout(saveTimerRef.current);
        saveTimerRef.current = null;
      }
    };
  }, [
    isProjectReady,
    canvasGenerationDialogs,
    layers,
    projectId,
    queueProjectLayoutSave,
    refs,
    viewport,
  ]);

  return {
    projectId,
    isProjectReady,
    projectIdRef,
    createProjectResourceForLayer,
    appendCanvasLayersWithResources,
    applyProjectSnapshot,
  };
}