Dont count unrecorded time for history_stats

[karwosts]

Proposed change

History stats seems to have undesired behavior when the observed window starts earlier than what data is available in the recorder. Consider the following case:

• Your recorder is set for 10 days history
• You have a history stats to monitor "How long has the sprinkler been on in the last 7 days"
• You haven't used sprinklers in a long time and all previous states are purged from the recorder.
• You turn on the sprinklers for the first time.
• The history stats sensor immediately jumps to 168 hours of on time, despite that it is actually only on for a few seconds.

I see this kind of bug reported many times and it's always difficult to explain why this happens. The reason is because history_stats currently looks for the first datapoint that it can find in the recorder, and it backdates this to the start of the observation window.

I would like to have a discussion if this is the correct behavior or not, since it seems pretty wrong to me.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes History stats sensor (type "time") shows incorrect values #114762 fixes History Stats reports erroneous values if duration is longer than Recorder purge_keep_days #125085
• This PR is related to issue:
• Link to documentation pull request:

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