3-data-types.md

3. Data Types

3.1 Service

Field	Type	Description
service_id	u64	Auto-incremented unique identifier
merchant	Address	Service owner's address
name	String	Display name of the service
price	i128	Amount charged per period
period_secs	u64	Billing cycle duration in seconds
trial_period_secs	u64	Free trial duration in seconds (0 = no trial)
approve_periods	u64	Number of periods to pre-approve when pay_upfront = true
is_active	bool	Whether the service accepts new subscriptions
created_at	u64	Ledger timestamp at creation

3.2 Subscription

Field	Type	Description
sub_id	u64	Auto-incremented unique identifier
subscriber	Address	Subscriber's address
service_id	u64	Associated service ID
price	i128	Price locked at subscription time
period_secs	u64	Billing cycle duration (copied from service)
trial_period_secs	u64	Trial duration (copied from service)
trial_end_ts	u64	Timestamp when trial ends (0 if no trial)
pay_upfront	bool	If true, process() will charge this subscription on each cycle
service_end_ts	u64	Timestamp when current active period expires
next_charge_ts	u64	Next time process() will attempt to charge
created_at	u64	Ledger timestamp at creation

3.3 ProcessResult

Field	Type	Description
charged	u32	Subscriptions successfully charged
failed	u32	Subscriptions where payment failed (auto-cancelled)
skipped	u32	Subscriptions not yet due or not pay_upfront

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