[time] Add template platform

[RFDarter]

What does this implement/fix?

Add a template platform. Allows the use of the time component on offline devices.

Also adds the possibily to change the system time by code

Types of changes

• [ ] Bugfix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Other

Related issue or feature (if applicable): fixes

Pull request in esphome-docs with documentation (if applicable): esphome/esphome-docs#<esphome-docs PR number goes here>

Test Environment

• [x] ESP32
• [ ] ESP32 IDF
• [ ] ESP8266
• [ ] RP2040
• [ ] BK72xx
• [ ] RTL87xx

Example entry for config.yaml:

esphome:
  name: time

esp32:
    board: nodemcu-32s

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

web_server:
  version: 3

logger:
  level: debug

time:
  - platform: template
    id: template_time
    timezone: Europe/Berlin

button:
  - platform: template
    name: hit me
    on_press: 
      then:
        - system_time.set: 
            id: template_time
            datetime: "2034-10-05 10:10"

datetime:
  - platform: template
    name: Set System Time
    optimistic: true
    type: datetime
    on_value:
      then:
        lambda: |-
          id(template_time).set_time(x);

  - platform: template
    name: Set System Time UTC
    optimistic: true
    type: datetime
    on_value:
      then:
        lambda: |-
          id(template_time).set_time(x, true);

interval:
  - interval: 1s
    then:
        - logger.log:
            format: "seconds: %d"
            args: [ 'id(template_time).timestamp_now()' ]
        - logger.log:
            format: "utc: %s"
            args: [ 'id(template_time).utcnow().strftime("%Y-%m-%d %H:%M:%S").c_str()' ]
        - logger.log:
            format: "local: %s"
            args: [ 'id(template_time).now().strftime("%Y-%m-%d %H:%M:%S").c_str()' ]

Checklist:

• [x] The code change is tested and works locally.
• [ ] Tests have been added to verify that the new code works (under tests/ folder).

If user exposed functionality or configuration variables are added/changed:

• [ ] Documentation added/updated in esphome-docs.

[probot-esphome[bot]]

Hey there @ottowinter, mind taking a look at this pull request as it has been labeled with an integration (time) you are listed as a code owner for? Thanks! _{^{(message by CodeOwnersMention)}}

[probot-esphome[bot]]

Hey there @RFDarter, Thanks for submitting this pull request! Can you add yourself as a codeowner for this integration? This way we can notify you if a bug report for this integration is reported. In __init__.py of the integration, please add:

CODEOWNERS = ["@RFDarter"]

And run script/build_codeowners.py

_{^{(message by NeedsCodeownersLabel)}}

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 55.10%. Comparing base (4d8b5ed) to head (e04ead4). Report is 2148 commits behind head on dev.

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #7621      +/-   ##
==========================================
+ Coverage   53.70%   55.10%   +1.39%     
==========================================
  Files          50       50              
  Lines        9408     9905     +497     
  Branches     1654     1354     -300     
==========================================
+ Hits         5053     5458     +405     
- Misses       4056     4097      +41     
- Partials      299      350      +51     

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[SodaWithoutSparkles]

What actually is still blocking this component? Is it just the docs?

[RFDarter]

Yep, docs are needed before it gets in the list of jessy to review it. My devcontainer is making me trouble at the moment and i haven't had time time to fix it.

[github-actions[bot]]

There hasn't been any activity on this pull request recently. This pull request has been automatically marked as stale because of that and will be closed if no further activity occurs within 7 days. If you are the author of this PR, please leave a comment if you want to keep it open. Also, please rebase your PR onto the latest dev branch to ensure that it's up to date with the latest changes. Thank you for your contribution!