mdw@git.distorted.org.uk Git - tripe-android/blob - progress.scala

   1 /* -*-scala-*-
   2  *
   3  * Reporting progress for long-running jobs
   4  *
   5  * (c) 2018 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of the Trivial IP Encryption (TrIPE) Android app.
  11  *
  12  * TrIPE is free software: you can redistribute it and/or modify it under
  13  * the terms of the GNU General Public License as published by the Free
  14  * Software Foundation; either version 3 of the License, or (at your
  15  * option) any later version.
  16  *
  17  * TrIPE is distributed in the hope that it will be useful, but WITHOUT
  18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with TrIPE.  If not, see <https://www.gnu.org/licenses/>.
  24  */
  25
  26 package uk.org.distorted.tripe; package object progress {
  27
  28 /*----- Imports -----------------------------------------------------------*/
  29
  30 import scala.collection.mutable.{Publisher, Subscriber};
  31
  32 import java.lang.System.currentTimeMillis;
  33
  34 /*----- Progress displays -------------------------------------------------*/
  35
  36 trait Model {
  37   protected val t0 = currentTimeMillis;
  38
  39   def what: String;
  40   def max: Long;
  41
  42   def eta(cur: Long): Double = {
  43     /* Report the estimated time remaining in seconds, or -1 if no idea.
  44      *
  45      * The model here is very stupid.  Weird jobs should override this and
  46      * do something more sensible.
  47      */
  48
  49     val max = this.max;
  50     val delta = currentTimeMillis - t0
  51     if (max < 0 || cur <= 0) -1 else delta*(max - cur)/cur.toDouble
  52   }
  53
  54   protected def fmt1(n: Long): String = n.toString;
  55
  56   def format(cur: Long): String = {
  57     val max = this.max;
  58     val fc = fmt1(cur);
  59     if (max >= 0) { val fm = fmt1(max); s"%${fm.length}s/%s".format(fc, fm) }
  60     else if (cur > 0) fc
  61     else ""
  62   }
  63 }
  64
  65 class SimpleModel(val what: String, val max: Long) extends Model;
  66
  67 private val UDATA = Seq("kB", "MB", "GB", "TB", "PB", "EB");
  68
  69 trait DataModel extends Model {
  70   override def fmt1(n: Long): String = {
  71     val (x, u) = ((n.toDouble, "B ") /: UDATA) { (xu, n) => (xu, n) match {
  72       case ((x, u), name) if x >= 1024.0 => (x/1024.0, name)
  73       case (xu, _) => xu
  74     } }
  75     f"$x%6.1f$u%s"
  76   }
  77 }
  78
  79 trait BaseReporter {
  80   def done();
  81   def failed(e: Exception);
  82 }
  83
  84 trait JobReporter extends BaseReporter {
  85   def step(cur: Long);
  86   def change(model: Model, cur: Long);
  87 }
  88
  89 trait OperationReporter extends BaseReporter {
  90   def step(detail: String);
  91 }
  92
  93 def withReporter[T, P <: BaseReporter]
  94         (rep: P, body: P => T): T = {
  95   val ret = try { body(rep) }
  96   catch { case e: Exception => rep.failed(e); throw e; }
  97   rep.done();
  98   ret
  99 }
 100
 101 trait Eyecandy {
 102   def note(msg: String);
 103   def clear();
 104   def commit();
 105   def record(msg: String) { note(msg); commit(); }
 106   def done();
 107   def cancelled() { failed("cancelled"); }
 108   def failed(msg: String);
 109
 110   def beginJob(model: Model): JobReporter
 111     // = new JobReporter(model);
 112
 113   def beginOperation(what: String): OperationReporter
 114     // = new OperationReporter(what);
 115
 116   def job[T](model: Model)(body: JobReporter => T): T =
 117     withReporter(beginJob(model), body);
 118
 119   def operation[T](what: String)(body: OperationReporter => T): T =
 120     withReporter(beginOperation(what), body);
 121 }
 122
 123 /*----- That's all, folks -------------------------------------------------*/
 124
 125 }