package ports

import (
	"context"
	"fmt"

	"galaxy/user/internal/domain/common"
	"galaxy/user/internal/domain/entitlement"
)

// EntitlementHistoryStore persists immutable entitlement period records and
// later close-state updates.
type EntitlementHistoryStore interface {
	// Create stores one new entitlement period history record. Implementations
	// must wrap ErrConflict when record.RecordID already exists.
	Create(ctx context.Context, record entitlement.PeriodRecord) error

	// GetByRecordID returns the entitlement period history record identified by
	// recordID.
	GetByRecordID(ctx context.Context, recordID entitlement.EntitlementRecordID) (entitlement.PeriodRecord, error)

	// ListByUserID returns every entitlement period history record owned by
	// userID.
	ListByUserID(ctx context.Context, userID common.UserID) ([]entitlement.PeriodRecord, error)

	// Update replaces one stored entitlement period history record.
	Update(ctx context.Context, record entitlement.PeriodRecord) error
}

// EntitlementSnapshotStore persists the read-optimized current entitlement
// snapshot.
type EntitlementSnapshotStore interface {
	// GetByUserID returns the current entitlement snapshot for userID.
	GetByUserID(ctx context.Context, userID common.UserID) (entitlement.CurrentSnapshot, error)

	// Put stores the current entitlement snapshot for record.UserID.
	Put(ctx context.Context, record entitlement.CurrentSnapshot) error
}

// GrantEntitlementInput stores one atomic transition from a current free
// entitlement state to a current paid state.
type GrantEntitlementInput struct {
	// ExpectedCurrentSnapshot stores the exact snapshot that must still be
	// current before the mutation commits.
	ExpectedCurrentSnapshot entitlement.CurrentSnapshot

	// ExpectedCurrentRecord stores the current effective free period that must
	// still be current before the mutation commits.
	ExpectedCurrentRecord entitlement.PeriodRecord

	// UpdatedCurrentRecord stores ExpectedCurrentRecord after the close metadata
	// is applied.
	UpdatedCurrentRecord entitlement.PeriodRecord

	// NewRecord stores the new paid entitlement history segment.
	NewRecord entitlement.PeriodRecord

	// NewSnapshot stores the new current effective entitlement snapshot.
	NewSnapshot entitlement.CurrentSnapshot
}

// Validate reports whether GrantEntitlementInput is structurally complete.
func (input GrantEntitlementInput) Validate() error {
	if err := input.ExpectedCurrentSnapshot.Validate(); err != nil {
		return fmt.Errorf("grant entitlement input expected current snapshot: %w", err)
	}
	if err := input.ExpectedCurrentRecord.Validate(); err != nil {
		return fmt.Errorf("grant entitlement input expected current record: %w", err)
	}
	if err := input.UpdatedCurrentRecord.Validate(); err != nil {
		return fmt.Errorf("grant entitlement input updated current record: %w", err)
	}
	if err := input.NewRecord.Validate(); err != nil {
		return fmt.Errorf("grant entitlement input new record: %w", err)
	}
	if err := input.NewSnapshot.Validate(); err != nil {
		return fmt.Errorf("grant entitlement input new snapshot: %w", err)
	}
	if input.ExpectedCurrentSnapshot.UserID != input.ExpectedCurrentRecord.UserID ||
		input.ExpectedCurrentSnapshot.UserID != input.UpdatedCurrentRecord.UserID ||
		input.ExpectedCurrentSnapshot.UserID != input.NewRecord.UserID ||
		input.ExpectedCurrentSnapshot.UserID != input.NewSnapshot.UserID {
		return fmt.Errorf("grant entitlement input all records must belong to the same user id")
	}
	if input.ExpectedCurrentRecord.RecordID != input.UpdatedCurrentRecord.RecordID {
		return fmt.Errorf("grant entitlement input updated current record must preserve record id")
	}

	return nil
}

// ExtendEntitlementInput stores one atomic extension of a current finite paid
// entitlement state.
type ExtendEntitlementInput struct {
	// ExpectedCurrentSnapshot stores the exact snapshot that must still be
	// current before the mutation commits.
	ExpectedCurrentSnapshot entitlement.CurrentSnapshot

	// NewRecord stores the appended entitlement history segment that extends the
	// current paid state.
	NewRecord entitlement.PeriodRecord

	// NewSnapshot stores the replacement current effective entitlement snapshot.
	NewSnapshot entitlement.CurrentSnapshot
}

// Validate reports whether ExtendEntitlementInput is structurally complete.
func (input ExtendEntitlementInput) Validate() error {
	if err := input.ExpectedCurrentSnapshot.Validate(); err != nil {
		return fmt.Errorf("extend entitlement input expected current snapshot: %w", err)
	}
	if err := input.NewRecord.Validate(); err != nil {
		return fmt.Errorf("extend entitlement input new record: %w", err)
	}
	if err := input.NewSnapshot.Validate(); err != nil {
		return fmt.Errorf("extend entitlement input new snapshot: %w", err)
	}
	if input.ExpectedCurrentSnapshot.UserID != input.NewRecord.UserID ||
		input.ExpectedCurrentSnapshot.UserID != input.NewSnapshot.UserID {
		return fmt.Errorf("extend entitlement input all records must belong to the same user id")
	}

	return nil
}

// RevokeEntitlementInput stores one atomic transition from a current paid
// entitlement state to a new free state.
type RevokeEntitlementInput struct {
	// ExpectedCurrentSnapshot stores the exact snapshot that must still be
	// current before the mutation commits.
	ExpectedCurrentSnapshot entitlement.CurrentSnapshot

	// ExpectedCurrentRecord stores the current effective paid period that must
	// still be current before the mutation commits.
	ExpectedCurrentRecord entitlement.PeriodRecord

	// UpdatedCurrentRecord stores ExpectedCurrentRecord after the close metadata
	// is applied.
	UpdatedCurrentRecord entitlement.PeriodRecord

	// NewRecord stores the newly created free entitlement period.
	NewRecord entitlement.PeriodRecord

	// NewSnapshot stores the replacement current effective free snapshot.
	NewSnapshot entitlement.CurrentSnapshot
}

// Validate reports whether RevokeEntitlementInput is structurally complete.
func (input RevokeEntitlementInput) Validate() error {
	if err := input.ExpectedCurrentSnapshot.Validate(); err != nil {
		return fmt.Errorf("revoke entitlement input expected current snapshot: %w", err)
	}
	if err := input.ExpectedCurrentRecord.Validate(); err != nil {
		return fmt.Errorf("revoke entitlement input expected current record: %w", err)
	}
	if err := input.UpdatedCurrentRecord.Validate(); err != nil {
		return fmt.Errorf("revoke entitlement input updated current record: %w", err)
	}
	if err := input.NewRecord.Validate(); err != nil {
		return fmt.Errorf("revoke entitlement input new record: %w", err)
	}
	if err := input.NewSnapshot.Validate(); err != nil {
		return fmt.Errorf("revoke entitlement input new snapshot: %w", err)
	}
	if input.ExpectedCurrentSnapshot.UserID != input.ExpectedCurrentRecord.UserID ||
		input.ExpectedCurrentSnapshot.UserID != input.UpdatedCurrentRecord.UserID ||
		input.ExpectedCurrentSnapshot.UserID != input.NewRecord.UserID ||
		input.ExpectedCurrentSnapshot.UserID != input.NewSnapshot.UserID {
		return fmt.Errorf("revoke entitlement input all records must belong to the same user id")
	}
	if input.ExpectedCurrentRecord.RecordID != input.UpdatedCurrentRecord.RecordID {
		return fmt.Errorf("revoke entitlement input updated current record must preserve record id")
	}

	return nil
}

// RepairExpiredEntitlementInput stores one atomic lazy-repair transition from
// an expired finite paid snapshot to a materialized free state.
type RepairExpiredEntitlementInput struct {
	// ExpectedExpiredSnapshot stores the exact expired snapshot that must still
	// be current before the repair commits.
	ExpectedExpiredSnapshot entitlement.CurrentSnapshot

	// NewRecord stores the newly created free entitlement period.
	NewRecord entitlement.PeriodRecord

	// NewSnapshot stores the replacement current effective free snapshot.
	NewSnapshot entitlement.CurrentSnapshot
}

// Validate reports whether RepairExpiredEntitlementInput is structurally
// complete.
func (input RepairExpiredEntitlementInput) Validate() error {
	if err := input.ExpectedExpiredSnapshot.Validate(); err != nil {
		return fmt.Errorf("repair expired entitlement input expected expired snapshot: %w", err)
	}
	if err := input.NewRecord.Validate(); err != nil {
		return fmt.Errorf("repair expired entitlement input new record: %w", err)
	}
	if err := input.NewSnapshot.Validate(); err != nil {
		return fmt.Errorf("repair expired entitlement input new snapshot: %w", err)
	}
	if input.ExpectedExpiredSnapshot.UserID != input.NewRecord.UserID ||
		input.ExpectedExpiredSnapshot.UserID != input.NewSnapshot.UserID {
		return fmt.Errorf("repair expired entitlement input all records must belong to the same user id")
	}

	return nil
}

// EntitlementLifecycleStore persists atomic entitlement timeline transitions
// that must keep history and current snapshot consistent.
type EntitlementLifecycleStore interface {
	// Grant atomically closes the current free period, creates a new paid
	// period, and replaces the current snapshot.
	Grant(ctx context.Context, input GrantEntitlementInput) error

	// Extend atomically appends one paid-history segment and replaces the
	// current snapshot.
	Extend(ctx context.Context, input ExtendEntitlementInput) error

	// Revoke atomically closes the current paid period, creates a new free
	// period, and replaces the current snapshot.
	Revoke(ctx context.Context, input RevokeEntitlementInput) error

	// RepairExpired atomically replaces one expired finite paid snapshot with a
	// materialized free state.
	RepairExpired(ctx context.Context, input RepairExpiredEntitlementInput) error
}