/*
 * Copyright (C) 2025 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.healthconnect.controller.data.fhir.api

import android.health.connect.HealthConnectManager
import android.health.connect.MedicalResourceId
import android.health.connect.datatypes.FhirResource
import androidx.core.os.asOutcomeReceiver
import com.android.healthconnect.controller.shared.usecase.IoDispatcher
import com.android.healthconnect.controller.shared.usecase.UseCaseResults
import javax.inject.Inject
import javax.inject.Singleton
import kotlinx.coroutines.CoroutineDispatcher
import kotlinx.coroutines.suspendCancellableCoroutine
import kotlinx.coroutines.withContext

@Singleton
class FhirUseCase
@Inject
constructor(
    private val healthConnectManager: HealthConnectManager,
    @IoDispatcher private val dispatcher: CoroutineDispatcher,
) {
    /**
     * Returns the corresponding [android.health.connect.datatypes.FhirResource] for given
     * [android.health.connect.MedicalResourceId].
     */
    suspend fun loadFhirResource(
        medicalResourceId: MedicalResourceId
    ): UseCaseResults<FhirResource> =
        withContext(dispatcher) {
            try {
                val medicalResources = suspendCancellableCoroutine { continuation ->
                    healthConnectManager.readMedicalResources(
                        listOf(medicalResourceId),
                        Runnable::run,
                        continuation.asOutcomeReceiver(),
                    )
                }
                if (medicalResources.isEmpty()) {
                    UseCaseResults.Failed(
                        IllegalStateException("No FHIR resource found for given $medicalResourceId")
                    )
                } else {
                    UseCaseResults.Success(medicalResources[0].fhirResource)
                }
            } catch (e: Exception) {
                UseCaseResults.Failed(e)
            }
        }
}