🪶 Aeon::ExceptionManager – 4 + 1 Architecture

Marks the moments that should never happen again.

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1️⃣ Logical View

Purpose:
Manages IceCube exception dates for Aeon recurrences, ensuring mutated occurrences are removed from original series.

Responsibilities - Insert exception times for skipped occurrences. - Apply “until” cutoffs for Change All Future. - Maintain serialized rules in repetition_rules.

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2️⃣ Process View

1. Mutator calls add_exception(timestamp, time) or end_recurrence_at.
2. Manager loads IceCube schedule via RecurrenceAdapter.
3. Adds add_exception_time or sets until:.
4. Serializes back into timestamp.
5. CacheInvalidation runs.

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3️⃣ Development View

File: app/services/aeon/exception_manager.rb

class Aeon::ExceptionManager
  def self.add_exception(timestamp, time)
    adapter = Aeon::RecurrenceAdapter.new(timestamp)
    schedule = adapter.schedule
    schedule.add_exception_time(time)
    timestamp.update!(repetition_rules: schedule.to_hash)
  end

  def self.end_recurrence_at(timestamp, cutoff)
    adapter = Aeon::RecurrenceAdapter.new(timestamp)
    schedule = adapter.schedule
    schedule.end_time = cutoff
    timestamp.update!(repetition_rules: schedule.to_hash)
  end
end

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4️⃣ Physical View

Attribute	Description
Store	Postgres (via Aeon::Timestamp)
Dependency	IceCube
Observability	Argus aeon.exception.added

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➕ 1 Scenario View

Scenario A – Skipping a Holiday

add_exception_time called for Dec 25.
Calendar hides that day automatically.

Scenario B – Splitting Series

end_recurrence_at called at edit boundary for Change All Future.

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