import { TRPCError } from '@trpc/server';
import { z } from 'zod';

import { serverDBEnv } from '@/config/db';
import { AsyncTaskModel } from '@/database/models/asyncTask';
import { ChunkModel } from '@/database/models/chunk';
import { FileModel } from '@/database/models/file';
import { authedProcedure, router } from '@/libs/trpc/lambda';
import { serverDatabase } from '@/libs/trpc/lambda/middleware';
import { FileService } from '@/server/services/file';
import { AsyncTaskStatus, AsyncTaskType } from '@/types/asyncTask';
import { FileListItem, QueryFileListSchema, UploadFileSchema } from '@/types/files';

const fileProcedure = authedProcedure.use(serverDatabase).use(async (opts) => {
  const { ctx } = opts;

  return opts.next({
    ctx: {
      asyncTaskModel: new AsyncTaskModel(ctx.serverDB, ctx.userId),
      chunkModel: new ChunkModel(ctx.serverDB, ctx.userId),
      fileModel: new FileModel(ctx.serverDB, ctx.userId),
      fileService: new FileService(ctx.serverDB, ctx.userId),
    },
  });
});

export const fileRouter = router({
  checkFileHash: fileProcedure
    .input(z.object({ hash: z.string() }))
    .mutation(async ({ ctx, input }) => {
      return ctx.fileModel.checkHash(input.hash);
    }),

  createFile: fileProcedure
    .input(UploadFileSchema.omit({ url: true }).extend({ url: z.string() }))
    .mutation(async ({ ctx, input }) => {
      const { isExist } = await ctx.fileModel.checkHash(input.hash!);

      const { id } = await ctx.fileModel.create(
        {
          fileHash: input.hash,
          fileType: input.fileType,
          knowledgeBaseId: input.knowledgeBaseId,
          metadata: input.metadata,
          name: input.name,
          size: input.size,
          url: input.url,
        },
        // if the file is not exist in global file, create a new one
        !isExist,
      );

      return { id, url: await ctx.fileService.getFullFileUrl(input.url) };
    }),
  findById: fileProcedure
    .input(
      z.object({
        id: z.string(),
      }),
    )
    .query(async ({ ctx, input }) => {
      const item = await ctx.fileModel.findById(input.id);
      if (!item) throw new TRPCError({ code: 'BAD_REQUEST', message: 'File not found' });

      return { ...item, url: await ctx.fileService.getFullFileUrl(item?.url) };
    }),

  getFileItemById: fileProcedure
    .input(
      z.object({
        id: z.string(),
      }),
    )
    .query(async ({ ctx, input }): Promise<FileListItem | undefined> => {
      const item = await ctx.fileModel.findById(input.id);

      if (!item) throw new TRPCError({ code: 'NOT_FOUND', message: 'File not found' });

      let embeddingTask = null;
      if (item.embeddingTaskId) {
        embeddingTask = await ctx.asyncTaskModel.findById(item.embeddingTaskId);
      }
      let chunkingTask = null;
      if (item.chunkTaskId) {
        chunkingTask = await ctx.asyncTaskModel.findById(item.chunkTaskId);
      }

      const chunkCount = await ctx.chunkModel.countByFileId(input.id);

      return {
        ...item,
        chunkCount,
        chunkingError: chunkingTask?.error,
        chunkingStatus: chunkingTask?.status as AsyncTaskStatus,
        embeddingError: embeddingTask?.error,
        embeddingStatus: embeddingTask?.status as AsyncTaskStatus,
        finishEmbedding: embeddingTask?.status === AsyncTaskStatus.Success,
        url: await ctx.fileService.getFullFileUrl(item.url!),
      };
    }),

  getFiles: fileProcedure.input(QueryFileListSchema).query(async ({ ctx, input }) => {
    const fileList = await ctx.fileModel.query(input);

    const fileIds = fileList.map((item) => item.id);
    const chunks = await ctx.chunkModel.countByFileIds(fileIds);

    const chunkTaskIds = fileList.map((result) => result.chunkTaskId).filter(Boolean) as string[];

    const chunkTasks = await ctx.asyncTaskModel.findByIds(chunkTaskIds, AsyncTaskType.Chunking);

    const embeddingTaskIds = fileList
      .map((result) => result.embeddingTaskId)
      .filter(Boolean) as string[];
    const embeddingTasks = await ctx.asyncTaskModel.findByIds(
      embeddingTaskIds,
      AsyncTaskType.Embedding,
    );

    const resultFiles = [] as any[];
    for (const { chunkTaskId, embeddingTaskId, ...item } of fileList as any[]) {
      const chunkTask = chunkTaskId ? chunkTasks.find((task) => task.id === chunkTaskId) : null;
      const embeddingTask = embeddingTaskId
        ? embeddingTasks.find((task) => task.id === embeddingTaskId)
        : null;

      const fileItem = {
        ...item,
        chunkCount: chunks.find((chunk) => chunk.id === item.id)?.count ?? null,
        chunkingError: chunkTask?.error ?? null,
        chunkingStatus: chunkTask?.status as AsyncTaskStatus,
        embeddingError: embeddingTask?.error ?? null,
        embeddingStatus: embeddingTask?.status as AsyncTaskStatus,
        finishEmbedding: embeddingTask?.status === AsyncTaskStatus.Success,
        url: await ctx.fileService.getFullFileUrl(item.url!),
      } as FileListItem;
      resultFiles.push(fileItem);
    }

    return resultFiles;
  }),

  removeAllFiles: fileProcedure.mutation(async ({ ctx }) => {
    return ctx.fileModel.clear();
  }),

  removeFile: fileProcedure.input(z.object({ id: z.string() })).mutation(async ({ input, ctx }) => {
    const file = await ctx.fileModel.delete(input.id, serverDBEnv.REMOVE_GLOBAL_FILE);

    if (!file) return;

    // delele the file from remove from S3 if it is not used by other files
    await ctx.fileService.deleteFile(file.url!);
  }),

  removeFileAsyncTask: fileProcedure
    .input(
      z.object({
        id: z.string(),
        type: z.enum(['embedding', 'chunk']),
      }),
    )
    .mutation(async ({ ctx, input }) => {
      const file = await ctx.fileModel.findById(input.id);

      if (!file) return;

      const taskId = input.type === 'embedding' ? file.embeddingTaskId : file.chunkTaskId;

      if (!taskId) return;

      await ctx.asyncTaskModel.delete(taskId);
    }),

  removeFiles: fileProcedure
    .input(z.object({ ids: z.array(z.string()) }))
    .mutation(async ({ input, ctx }) => {
      const needToRemoveFileList = await ctx.fileModel.deleteMany(
        input.ids,
        serverDBEnv.REMOVE_GLOBAL_FILE,
      );

      if (!needToRemoveFileList || needToRemoveFileList.length === 0) return;

      // remove from S3
      await ctx.fileService.deleteFiles(needToRemoveFileList.map((file) => file.url!));
    }),
});

export type FileRouter = typeof fileRouter;