/*
 * Copyright (C) 2018 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.tools.analytics

import com.google.common.annotations.VisibleForTesting

/**
 * Used in tests to fake out the Environment code used in production to allow injecting custom
 * environment variable values.
 */
@VisibleForTesting
object EnvironmentFakes {
  /**
   * Helper to fake the ANDROID_SDK_HOME environment variable to be set to `path`.
   */
  fun setCustomAndroidSdkHomeEnvironment(path: String) {
    setSingleProperty("ANDROID_SDK_HOME", path)
  }

  fun setMap(map: Map<String, String>) {
    Environment.instance = object : Environment() {
      override fun getVariable(name: String): String? {
        return map[name]
      }
    }
  }

  fun setSingleProperty(key: String, value: String) {
    Environment.instance = object : Environment() {
      override fun getVariable(name: String): String? {
        return if (key == name) {
          value
        }
        else null
      }
    }
  }

  /** Helper to fake the ANDROID_SDK_HOME environment variable to be unset.  */
  fun setNoEnvironmentVariable() {
    Environment.instance = object : Environment() {
      override fun getVariable(name: String): String? {
        return null
      }
    }
  }

  /**
   * Helper to undo faking the environment variable reading.
   */
  fun setSystemEnvironment() {
    Environment.instance = Environment.SYSTEM
  }
}