import axios from "axios";
import Constants from "expo-constants";
import * as ImagePicker from "expo-image-picker";
import moment from 'moment';
import { all, call, delay, fork, put, select, takeEvery, takeLatest } from "redux-saga/effects";
import env from "../../env";
import { client } from '../../graphql/client';
import { INSERT_NEW_DOCUMENT } from "../../graphql/documents.queries";
import { axiosAuthInterceptorId } from "../../util/CleanAxios";
import { fetchImageFromUri, replaceAccents } from '../../util/uploadUtils';
import { selectBodyshop, selectCurrentUser } from "../user/user.selectors";
import {
  mediaUploadFailure,
  mediaUploadProgressOne,
  mediaUploadStart,
  mediaUploadSuccessOne
} from "./photos.actions";

import PhotosActionTypes from "./photos.types";

//Required to prevent headers from getting set and rejected from Cloudinary.
let cleanAxios = axios.create();
cleanAxios.interceptors.request.eject(axiosAuthInterceptorId);



export function* onOpenImagePicker() {
  yield takeLatest(PhotosActionTypes.OPEN_IMAGE_PICKER, openImagePickerAction);
}

export function* openImagePickerAction({ payload: jobid }) {
  try {
    if (Constants.platform.ios) {
      const cameraRollStatus =
        yield ImagePicker.requestMediaLibraryPermissionsAsync();
      const cameraStatus = yield ImagePicker.requestCameraPermissionsAsync();
      if (
        cameraRollStatus.status !== "granted" ||
        cameraStatus.status !== "granted"
      ) {
        alert("Sorry, we need these permissions to make this work!");
        return;
      }
    }
    let result = yield ImagePicker.launchImageLibraryAsync({
      mediaTypes: ["images", "videos"],
      aspect: [4, 3],
      quality: 1,
      allowsMultipleSelection: true,
      exif: true,
    });
    if (!(result.canceled)) {
      yield put(mediaUploadStart({ photos: result.assets, jobid }));
    }
  } catch (error) {
    console.log("Saga Error: open Picker", error);
  }
}

export function* onMediaUploadStart() {
  yield takeLatest(PhotosActionTypes.MEDIA_UPLOAD_START, mediaUploadStartAction);
}

export function* mediaUploadStartAction({ payload: { photos, jobid } }) {
  try {
    console.log("Starting upload for", photos.length, "photos");

    const bodyshop = yield select(selectBodyshop);

    // Process photos in batches to avoid overwhelming the system
    const batchSize = 3; // Upload 3 photos concurrently
    const batches = [];

    for (let i = 0; i < photos.length; i += batchSize) {
      batches.push(photos.slice(i, i + batchSize));
    }
    // Process each batch sequentially, but photos within batch concurrently
    for (const batch of batches) {
      const uploadTasks = batch.map((photo, index) =>
        fork(uploadSinglePhoto, photo, bodyshop, index, jobid)
      );
      // Wait for current batch to complete before starting next batch
      yield all(uploadTasks);
      // Small delay between batches to prevent overwhelming the server
      yield delay(100);
    }
    //yield put(mediaUploadSuccess(photo));

  } catch (error) {
    console.log("Saga Error: upload start", error, error.stack);
    yield put(mediaUploadFailure(error.message));
  }
}

function* uploadSinglePhoto(photo, bodyshop, index, jobid) {
  try {
    yield put(mediaUploadProgressOne({ ...photo, status: 'starting', progress: 0 }));

    const photoBlob = yield fetchImageFromUri(photo.uri); //has a name, and type. 
    const extension = photoBlob.data?.name?.split('.').pop();

    const key = `${bodyshop.id}/${jobid}/${replaceAccents(
      photoBlob.data.name
    ).replace(/[^A-Z0-9]+/gi, "_")}-${new Date().getTime()}.${extension}`

    if (bodyshop.uselocalmediaserver) {
      yield call(uploadToLocalMediaServer, photo, photoBlob, extension, key, bodyshop, jobid);
    } else {
      yield call(uploadToImageProxy, photo, photoBlob, extension, key, bodyshop, jobid);
    }

    yield put(mediaUploadSuccessOne(photo));

  } catch (error) {
    console.log(`Upload failed for photo ${photo.uri}:`, error);
    yield put(mediaUploadFailure({ ...photo, status: "error", error: error.message }));
  }
}

function* uploadToLocalMediaServer(photo, key) {
  try {
    //   yield put(mediaUploadProgress({ photoId, status: 'uploading', progress: 25 }));

    //   const formData = new FormData();
    //   formData.append('file', {
    //     uri: photo.uri,
    //     type: photo.type || 'image/jpeg',
    //     name: photo.fileName || `photo_${Date.now()}.jpg`,
    //   });

    //   yield put(mediaUploadProgress({ photoId, status: 'uploading', progress: 50 }));

    //   const response = yield call(fetch, 'YOUR_LOCAL_MEDIA_SERVER_ENDPOINT', {
    //     method: 'POST',
    //     body: formData,
    //     headers: {
    //       'Content-Type': 'multipart/form-data',
    //     },
    //   });

    //   yield put(mediaUploadProgress({ photoId, status: 'uploading', progress: 75 }));

    //   if (!response.ok) {
    //     throw new Error(`Upload failed: ${response.status}`);
    //   }

    //   const result = yield call([response, 'json']);
    //   yield put(mediaUploadProgress({ photoId, status: 'completed', progress: 100 }));

    //   return result;

  } catch (error) {
    throw new Error(`Local media server upload failed: ${error.message}`);
  }
}

function* uploadToImageProxy(photo, photoBlob, extension, key, bodyshop, jobid) {
  try {
    yield put(mediaUploadProgressOne({ ...photo, status: 'uploading', }));
    //Get the signed url allowing us to PUT to S3.
    const signedURLResponse = yield call(axios.post,
      `${env.API_URL}/media/imgproxy/sign`,
      {
        filenames: [key],
        bodyshopid: bodyshop.id,
        jobid,
      }
    );

    if (signedURLResponse.status !== 200) {
      console.log("Error Getting Signed URL", signedURLResponse.statusText);
      throw new Error(`Error getting signed URL : ${signedURLResponse.statusText}`);
    }
    const { presignedUrl: preSignedUploadUrlToS3, key: s3Key } =
      signedURLResponse.data.signedUrls[0];

    let uploadResult
    try {
      uploadResult = yield new Promise((resolve, reject) => {
        const xhr = new XMLHttpRequest();
        xhr.open("PUT", preSignedUploadUrlToS3);
        xhr.setRequestHeader("Content-Type", photoBlob.type);

        xhr.upload.onprogress = (e) => {
          console.log("*** ~ awaitnewPromise ~ event:", e);
          if (e.lengthComputable) {
            console.log(`Upload progress for ${photo.uri}:`, e.loaded / e.total);
            put(mediaUploadProgressOne({ ...photo, progress: e.loaded / e.total }));
          }
        };

        xhr.onload = () => {
          if (xhr.status === 200) {
            resolve(true);
          } else {
            reject(new Error(`Upload failed: ${xhr.statusText}`));
          }
        };

        xhr.onerror = (req, event) => {
          reject(new Error("Network error"));
        };

        xhr.send(photoBlob);
      });
    } catch (error) {
      console.log("Error uploading to S3", error.message, error.stack);
      throw error;
    }

    if (uploadResult) {
      //Create doc record. 
      const uploaded_by = yield select(selectCurrentUser);

      const [date, time] = photo.exif?.DateTime?.split(' ') || [];
      const [year, month, day] = date ? date.split(':') : [];
      const [hours, minutes, seconds] = time ? time.split(':') : [];
      const pictureMoment = moment(`${year}-${month}-${day}T${hours}:${minutes}:${seconds}`);

      const documentInsert = yield call(client.mutate, ({
        mutation: INSERT_NEW_DOCUMENT,
        variables: {
          docInput: [
            {
              ...(jobid ? { jobid: jobid } : {}),
              uploaded_by: uploaded_by.email,
              key: s3Key,
              type: photoBlob.type,
              extension: extension,
              bodyshopid: bodyshop.id,
              size: photoBlob.size,
              ...(photo.exif?.DateTime //TODO :Need to find how to do this. 
                ? { takenat: pictureMoment }
                : {}),
            },
          ],
        },
      }));
      console.log("*** ~ uploadToImageProxy ~ documentInsert:", JSON.stringify(documentInsert, null, 2));
    }

  } catch (error) {
    console.log("Error uploading to image proxy", JSON.stringify(error));
    throw new Error(`Image proxy upload failed: ${error.message}`);
  }
}

// Handle cancellation of uploads
export function* onCancelUpload() {
  yield takeEvery(PhotosActionTypes.CANCEL_UPLOAD, cancelUploadAction);
}

function* cancelUploadAction({ payload: photoId }) {
  // const task = uploadTasks.get(photoId);
  // if (task) {
  //   yield cancel(task);
  //   uploadTasks.delete(photoId);
  //   yield put(mediaUploadFailure({ photoId, error: 'Upload cancelled' }));
  // }
}

export function* photosSagas() {
  yield all([
    call(onOpenImagePicker),
    call(onMediaUploadStart),
    //call(onCancelUpload)
  ]);
}