[mythtv] V2Capture::AddCardInput

[David Engel]

On Tue, Jul 05, 2022 at 05:05:04PM -0600, John P Poet wrote:
> On Tue, Jul 5, 2022 at 1:53 PM John P Poet <jppoet at gmail.com> wrote:
> 
> > On Tue, Jul 5, 2022 at 1:38 PM David Engel <david at istwok.net> wrote:
> >
> >> On Tue, Jul 05, 2022 at 02:17:08PM -0500, David Engel wrote:
> >> > On Tue, Jul 05, 2022 at 11:54:15AM -0600, John P Poet wrote:
> >> > > On Tue, Jul 5, 2022 at 11:02 AM David Engel <david at istwok.net> wrote:
> >> > >
> >> > > > On Tue, Jul 05, 2022 at 09:57:36AM -0600, John P Poet wrote:
> >> > > > > On Tue, Jul 5, 2022 at 9:46 AM David Engel <david at istwok.net>
> >> wrote:
> >> > > > >
> >> > > > > > On Tue, Jul 05, 2022 at 08:28:43AM -0600, John P Poet wrote:
> >> > > > > > > On Tue, Jul 5, 2022, 12:33 AM Klaas de Waal <
> >> klaas.de.waal at gmail.com
> >> > > > >
> >> > > > > > wrote:
> >> > > > > > > > On Tue, 5 Jul 2022 at 05:13, John P Poet <jppoet at gmail.com>
> >> wrote:
> >> > > > > > > >> On Mon, Jul 4, 2022 at 8:30 PM David Engel <
> >> david at istwok.net>
> >> > > > wrote:
> >> > > > > > > >>> On Mon, Jul 04, 2022 at 08:03:45PM -0600, John P Poet
> >> wrote:
> >> > > > > > > >>> > Hi all,
> >> > > > > > > >>> >
> >> > > > > > > >>> > I don't think the call to
> >> CardUtil::IsUniqueDisplayName()
> >> > > > should be
> >> > > > > > > >>> fatal
> >> > > > > > > >>> > in V2Capture::AddCardInput. *Only the last two
> >> characters* of
> >> > > > the
> >> > > > > > > >>> > DisplayName are considered to determine if it is
> >> unique. That
> >> > > > > > unfairly
> >> > > > > > > >>> > penalizes users who use a theme which can display more
> >> than two
> >> > > > > > > >>> characters.
> >> > > > > > > >>> >
> >> > > > > > > >>> > Thoughts?
> >> > > > > > > >>>
> >> > > > > > > >>> The last two characters of the short, display name can be
> >> and is
> >> > > > used
> >> > > > > > > >>> in themes.  Without enforcing this uniqueness
> >> requirement, themes
> >> > > > > > that
> >> > > > > > > >>> use the short, dispaly name will present ambiguous inputs.
> >> > > > > > > >>>
> >> > > > > > > >>> David
> >> > > > > > > >>>
> >> > > > > > > >>
> >> > > > > > > >> It should be up to the user to choose Display Names which
> >> work
> >> > > > with
> >> > > > > > the
> >> > > > > > > >> theme they have chosen. Why penalize some users just to
> >> protect
> >> > > > other
> >> > > > > > users
> >> > > > > > > >> from making a poor choice?
> >> > > > > > > >>
> >> > > > > > > >> John
> >> > > > > > > >>
> >> > > > > > > >> As I understand it, it is only a presentation string so it
> >> does
> >> > > > not
> >> > > > > > > > matter for correct operation.
> >> > > > > > > > Consider using a 4-tuner HDHomeRun box. It is not really
> >> important
> >> > > > > > which
> >> > > > > > > > of the four tuners are used so a string like "HC" (short for
> >> > > > HDHomerun
> >> > > > > >
> >> > > > > > You are correct that the physical tuner doesn't matter.
> >> However, if
> >> > > > > > you care about scheduling or especially, having to support
> >> scheduling
> >> > > > > > issues, the logical tuner very much matters.
> >> > > > > >
> >> > > > > > > > Cable) could then be used for all four input connections.
> >> > > > > > > > So I suggest doing it the same as in mythtv-setup; generate
> >> a
> >> > > > default
> >> > > > > > that
> >> > > > > > > > is unique, e.g. "Input 12", but leave the decision to the
> >> user.
> >> > > > > >
> >> > > > > > It defaults to "Input XX", or at leat it used to.
> >> > > > > >
> >> > > > > > > Let's move CardUtil::IsUniqueDisplayName() to its own
> >> services API
> >> > > > call.
> >> > > > > > > Then the application can use it to warn the user of the
> >> consequences
> >> > > > of
> >> > > > > > > their choice.
> >> > > > > >
> >> > > > > > I strongly disagree.  Perhaps you never noticed, but the short,
> >> > > > > > display name is used in multiple places like the System Status
> >> screen
> >> > > > > > and the Change Input menu in live TV.  The intent was to
> >> replace input
> >> > > > > > number with the [unique] short, display name in every
> >> user-facing
> >> > > > > > location.  The reason for that was to more gracefully handle the
> >> > > > > > proliferation of inpuss and increasingly, meaningless numbers.
> >> In my
> >> > > > > > case, I don't even know nor care what my input numbers are
> >> anymore.
> >> > > > > >
> >> > > > > > As for the length of the unique part, I think 2 characters is
> >> enough.
> >> > > > > > However, as I stated in my private email, 3 could probably work
> >> if
> >> > > > > > theme designers agree.
> >> > > > > >
> >> > > > > > David
> >> > > > > >
> >> > > > >
> >> > > > > David, I generally agree with you on most things, but not this.
> >> At least
> >> > > > > not completely. I agree about the part of input numbers being
> >> > > > meaningless.
> >> > > > > I disagree that we should punish users of *some* themes just
> >> because
> >> > > > *other*
> >> > > > > themes went with the "short" name instead of the long one.
> >> > > > >
> >> > > > > You are right that I never noticed the short name being used in
> >> those
> >> > > > > places -- because with the Steppes theme, the short name is *not
> >> used
> >> > > > > anywhere*.
> >> > > >
> >> > > > I wouldn't call requiring 2 or 3 characters to be unique
> >> "punishing".
> >> > > > Is it really that hard?  I also think that's much better than
> >> risking
> >> > > > the intentional confussion of users just because they happen to
> >> change
> >> > > > themes.
> >> > > >
> >> > > > Look, display name must be unique in some way.  I see that as a
> >> given.
> >> > > > The question then becomes how to also make it unique when it's used
> >> in
> >> > > > a condensed format.  When I added the feature, I chose to use the
> >> last
> >> > > > two characters.  It was much simpler than adding yet another name
> >> and
> >> > > > it was easy code-wise, wasn't onerous for the user and was also the
> >> > > > most likely place a user would distinguish between two or more of
> >> the
> >> > > > same type of input -- Red 1/Red 2, Black 5/Black 6, etc.
> >> > > >
> >> > > > If you've got a another suggestion of how to take a unique, display
> >> > > > name and condense it down to 2/3 characters that are also unique,
> >> then
> >> > > > let's hear it.  I'm not wedded to the idea of using the last 2
> >> > > > characters.  I'll happily change my input names if you have another
> >> > > > way of maitaining uniqueness of both long and short names.
> >> > > >
> >> > > > David
> >> > >
> >> > >
> >> > > I can see an advantage to requiring that DisplayName be unique.
> >> However, we
> >> > > have never enforced that before. It is not enforced in mythtv-setup,
> >> and I
> >> > > am talking about the full DisplayName, not even the shortened version.
> >> >
> >> > I thought I'd put enforcement in there.  I know I updated the help
> >> > text and enforced it in the serviced API as you found out.  Thinking
> >> > back on it now, I'm not even sure mythtv-setup can be made to enforce
> >> > constraints at entry time.  It might have strongly suggested at exit
> >> > time like some other mis-configurations are handled.
> >> >
> >> > > I just recently tried to use the V2Capture::AddCardInput for the
> >> first time
> >> > > yesterday and used the same DisplayNames I always use, resulting in
> >> > > confusion when they were rejected. I had to track down the code to
> >> discover
> >> > > that it was only looking at the last two characters. If it had looked
> >> at
> >> > > the last three then I would not have been bit by that test. So,
> >> obviously *for
> >> > > me*, requiring the last three to be unique would have been fine.
> >> > >
> >> > > So, as a compromise I would like to change
> >> CardUtil::IsUniqueDisplayName to
> >> > > look at the last three characters. *Just* doing that would not change
> >> the
> >> > > "value" of the "short" version of the DisplayName, which means themes
> >> would
> >> > > continue to display the short version as they do now.
> >> > >
> >> > > Alternatively, we could change the *definition* of the short
> >> DisplayName to
> >> > > be three characters.  If a theme does not have enough room for three
> >> > > characters, the result will be the last character overlapping the next
> >> > > field by some amount. The information would be displayed, it just
> >> might not
> >> > > look good in some themes.
> >> >
> >> > As already noted, I'm fine with 3 being the number of characters
> >> > counted.  In addition, 4 characters shalt not be counted and 5 is
> >> > right out. :)
> >>
> >> FYI, I'm also fine with defining an optionally, more complex format
> >> that splits the long and short/must-be-unique names.  For example,
> >> with a / (or other agreed upon delimier) the user could enter
> >>
> >>     HDHR-Prime/A1
> >>     HDHR-Prime/B3
> >>     Ceton/C5
> >>
> >> If the delimiter is not present, the last n characters are checked for
> >> uniqueness, otherwise, the part after the delimiter is used.  I know
> >> some might argue that that's more complex than just having separate
> >> fields.  I can understand that argument but don't necessarily agree
> >> with it.  Most users will be content with the default Input nn names.
> >>
> >> David
> >>
> >
> > That works for me and gives the flexibility I was after.
> >
> > John
> >
> 
> David,
> 
> I am attaching a patch for you to look at. One thing I was unable to find
> is where the "short" displayname is created for actual display purposes. I
> downloaded several themes and did not find a single example of the short
> displayname being used anywhere. Believe it or not, most themes are still
> showing the input number!

I think your patch is okay.  Although, it looks like it contains some
gratuitous, space changes.

Look for the progMap["input"] = ... line in ProgramInfo::ToMap().  I
wouldn't be surprised if my personal theme is the only one using it.
I didn't promote the change very much to theme developors and inertia
can be a hard thing to change.

David
-- 
David Engel
david at istwok.net