Twig - A logcat wrapper using Kotlin reified generics

twig.kt

package se.hellsoft.twig

import android.util.Log
import se.hellsoft.kotlinhacks.BuildConfig

/**
 * Verbose logging. Will be stripped from release builds.
 */
inline fun <reified T> T.logv(error: Throwable? = null, m: () -> String) {
  if (BuildConfig.DEBUG) {
    Twig.writeLog(Log.VERBOSE, T::class.java, m(), error)
  }
}

/**
 * Info logging. Will be stripped from release builds.
 */
inline fun <reified T> T.logi(error: Throwable? = null, m: () -> String) {
  if (BuildConfig.DEBUG) {
    Twig.writeLog(Log.INFO, T::class.java, m(), error)
  }
}

/**
 * Debug logging. Will be stripped from release builds.
 */
inline fun <reified T> T.logd(error: Throwable? = null, m: () -> String) {
  if (BuildConfig.DEBUG) {
    Twig.writeLog(Log.DEBUG, T::class.java, m(), error)
  }
}

/**
 * Log a warning. Will not be stripped from release builds.
 */
inline fun <reified T> T.logw(error: Throwable? = null, m: () -> String) {
  Twig.writeLog(Log.WARN, T::class.java, m(), error)
}

/**
 * Log an error. Will not be stripped from release builds.
 */
inline fun <reified T> T.loge(error: Throwable? = null, m: () -> String) {
  Twig.writeLog(Log.ERROR, T::class.java, m(), error)
}

/**
 * Simple log wrapper for Android projects in Kotlin.
 * This wrapper is not designed to be used from Java.
 */
object Twig {
  var logger: LogInterceptor? = null
  
  private val logcatLogger = object : LogInterceptor {
    override fun onLog(level: Int, tag: String, message: String, error: Throwable?) {
      if (error != null) {
        when (level) {
          Log.VERBOSE -> Log.v(tag, message, error)
          Log.DEBUG -> Log.d(tag, message, error)
          Log.INFO -> Log.i(tag, message, error)
          Log.WARN -> Log.w(tag, message, error)
          Log.ERROR -> Log.e(tag, message, error)
        }
      } else {
        when (level) {
          Log.VERBOSE -> Log.v(tag, message)
          Log.DEBUG -> Log.d(tag, message)
          Log.INFO -> Log.i(tag, message)
          Log.WARN -> Log.w(tag, message)
          Log.ERROR -> Log.e(tag, message)
        }
      }
    }
  }

  private fun buildTag(clazz: Class<*>): String {
    val packageName = clazz.`package`.name
    return if (packageName.length > 1) {
      clazz.name.substring(packageName.length + 1)
    } else {
      clazz.name
    }
  }

  fun writeLog(level: Int, clazz: Class<*>, message: String, error: Throwable? = null) {
    val tag = buildTag(clazz)

    logger?.onLog(level, tag, message, error)
  }

  interface LogInterceptor {
    fun onLog(level: Int, tag: String, message: String, error: Throwable? = null)
  }

}