VixenModules.Editor.TimedSequenceEditor.MarkManager.buttonGenerateBeatMarks_Click C# (CSharp) Method

        private void buttonGenerateBeatMarks_Click(object sender, EventArgs e)
        {
            if (MessageBox.Show("This operation will determine the average beat from the selected marks, and apply them for the rest of the song. Do you want to continue?", "Information", MessageBoxButtons.YesNo) == DialogResult.No)
                return;

            if (listViewMarks.SelectedItems.Count < 2) {
                MessageBox.Show("Select at least two marks to be able to determine an average time interval.", "Need more marks");
                return;
            }

            Common.Controls.TextDialog prompt = new Common.Controls.TextDialog("How long should the beats be generated for, in seconds? Leave blank to go to the end.");
            // the default prompt isn't enough to hold all the above text. Oops.
            prompt.Size = new Size(550, prompt.Size.Height);
            if (prompt.ShowDialog() == DialogResult.OK) {
                TimeSpan duration;
                bool conversionSuccess = TimeSpan.TryParseExact(prompt.Response, TimeFormats.PositiveFormats, null, out duration);
                if (!conversionSuccess && prompt.Response.Length == 0) {
                    conversionSuccess = true;
                    duration = TimeSpan.MaxValue;
                }

                if (conversionSuccess) {
                    TimeSpan earlistMark = TimeSpan.MaxValue;
                    TimeSpan latestMark = TimeSpan.MinValue;

                    foreach (ListViewItem item in listViewMarks.SelectedItems) {
                        if ((TimeSpan)item.Tag < earlistMark) {
                            earlistMark = (TimeSpan)item.Tag;
                        }
                        if ((TimeSpan)item.Tag > latestMark) {
                            latestMark = (TimeSpan)item.Tag;
                        }
                    }

                    int sourcesCount = listViewMarks.SelectedItems.Count;
                    TimeSpan interval = TimeSpan.FromTicks((latestMark - earlistMark).Ticks / (sourcesCount - 1));
                    double bpm = 60 / interval.TotalSeconds;

                    TimeSpan maxPossibleDuration = _timedSequenceEditorForm.Sequence.Length - latestMark;
                    if (duration > maxPossibleDuration)
                        duration = maxPossibleDuration;

                    int generatedMarks = (int)(duration.Ticks / interval.Ticks) - 1;

                    if (MessageBox.Show("From the selected marks, a beat interval of " + interval.ToString(@"s\.ff") +
                        " seconds was detected (" + bpm.ToString(@"#####.##") + " bpm). This will generate " + generatedMarks + " marks. Do you " +
                        "want to continue?", "Confirmation", MessageBoxButtons.YesNo) != DialogResult.Yes) {
                        return;
                    }

                    TimeSpan currentTime = latestMark + interval;
                    TimeSpan endTime = latestMark + duration;
                    while (currentTime <= endTime) {
                        _displayedCollection.Marks.Add(currentTime);
                        currentTime += interval;
                    }

                    _displayedCollection.Marks.Sort();
                    PopulateMarkListFromMarkCollection(_displayedCollection);
                    UpdateMarkCollectionInList(_displayedCollection);
                } else {
                    MessageBox.Show("Error parsing time: please use the format '<minutes>:<seconds>.<milliseconds>', or leave empty", "Error parsing time");
                }
            }
        }