package wristband

import (
	"context"
	"errors"
	"time"
)

// ErrClientCapReached is returned by ClientStore.CreateWithCap when the
// unrevoked client count is already at or above the configured cap
// (D-03/D-21, T-08-DCR-FLOOD). Register translates it into the exact PHP
// invalid_client_metadata "Registration temporarily unavailable" body.
var ErrClientCapReached = errors.New("wristband: dynamic client registration cap reached")

// ClientRecord is the app-agnostic persisted shape of an OAuth client row.
// fonoteka's GORM adapter (classes/auth/oauth_store.go) converts to/from
// its models.OAuthClient; wristband never imports GORM or fonoteka.
type ClientRecord struct {
	ID                      uint
	ClientID                string
	ClientSecretHash        *string // nil for public (auth method "none") clients
	ClientName              string
	RedirectURIs            []string
	GrantTypes              []string
	TokenEndpointAuthMethod string
	RegistrationIP          *string // nil for artisan-issued clients (D-19); never swept
	ConsentedAt             *time.Time
	RevokedAt               *time.Time
	ScopeCeiling            []string // nil/empty means no ceiling
	CreatedAt               time.Time
}

// AuthCodeRecord is the app-agnostic persisted shape of a pending or issued
// authorization row. Its full lifecycle (issue, exchange, replay) belongs to
// a later Phase 8 plan (08-03/08-04); this plan only needs the shape and the
// row-lock read so the Tx bundle is complete for T-08-CODE-REPLAY.
type AuthCodeRecord struct {
	ID                  uint
	RequestID           *string // non-nil while pending; nulled once a code is issued
	CodeHash            *string // nil while pending; set once a code is issued
	ClientID            string
	UserID              *uint // nil until consent
	RedirectURI         string
	Scopes              []string
	CollectionIDs       []uint
	CodeChallenge       string
	CodeChallengeMethod string
	Resource            *string
	State               *string
	ExpiresAt           time.Time
	UsedAt              *time.Time
	OfflineAccess       bool
}

// RefreshTokenRecord is the app-agnostic persisted shape of a refresh-token
// lineage row. Rotation/replay semantics belong to a later plan (08-04);
// this plan only needs the shape and the row-lock read for T-08-REFRESH-REPLAY.
type RefreshTokenRecord struct {
	ID            uint
	TokenHash     string
	APITokenID    *uint
	ClientID      string
	UserID        uint
	Scopes        []string
	CollectionIDs []uint
	ExpiresAt     time.Time
	RevokedAt     *time.Time
	RotatedToID   *uint
	OfflineAccess bool
}

// IssuedToken is what an AccessTokenIssuer mints: the one-time raw secret
// plus the persisted row id (for later Revoke calls).
type IssuedToken struct {
	ID     uint
	Secret string
}

// ClientStore persists OAuthClient rows. This plan (08-02) exercises
// ByClientID, CreateWithCap and SweepUnconsented through Register; Revoke
// belongs to a later connected-apps plan.
type ClientStore interface {
	ByClientID(ctx context.Context, clientID string) (*ClientRecord, error)
	// CreateWithCap creates rec only when the unrevoked client count is
	// below cap, atomically with the count check (T-08-DCR-FLOOD). It
	// returns ErrClientCapReached, leaving no row created, when the cap is
	// already reached. On success it fills rec.ID and rec.CreatedAt.
	CreateWithCap(ctx context.Context, rec *ClientRecord, cap int) error
	// SweepUnconsented deletes dynamically-registered (non-nil
	// RegistrationIP), still-unconsented clients created before olderThan.
	// Artisan-issued clients (nil RegistrationIP) are never swept (D-19).
	SweepUnconsented(ctx context.Context, olderThan time.Time) error
	// MarkConsented stamps ConsentedAt once for clientID unless it is
	// already set (idempotent; PHP OAuthConsentController::store's "if
	// ($client->consented_at === null)" guard, 08-05-PLAN.md D-08). A
	// consented client is never later swept by SweepUnconsented.
	MarkConsented(ctx context.Context, clientID string) error
}

// AuthCodeStore persists pending/issued authorization rows. ByCodeHashForUpdate
// is the row-lock read a later plan's code-exchange/replay-kill logic needs
// (T-08-CODE-REPLAY); it ships now so the Tx bundle does not change shape
// later.
type AuthCodeStore interface {
	CreatePending(ctx context.Context, rec *AuthCodeRecord) error
	ByRequestID(ctx context.Context, requestID string) (*AuthCodeRecord, error)
	ByCodeHashForUpdate(ctx context.Context, codeHash string) (*AuthCodeRecord, error)
	// MarkIssued turns a pending row into an issued authorization code
	// (PHP OAuthCodeManager::issueCode, 08-05-PLAN.md D-08): it nulls
	// RequestID, sets CodeHash/UserID, overwrites Scopes/CollectionIDs
	// with the consent-granted values (never the originally requested
	// ones), and extends ExpiresAt to the fresh code TTL.
	MarkIssued(ctx context.Context, id uint, codeHash string, userID uint, scopes []string, collectionIDs []uint, expiresAt time.Time) error
	MarkUsed(ctx context.Context, id uint) error
	// DeleteExpiredCodes removes pending and issued authorization-code rows
	// whose ExpiresAt is before now (D-17: wristband adds an expiry sweep
	// PHP lacks). used_at/request_id status is irrelevant to the decision:
	// only expiry drives deletion, so unexpired issued-but-unused rows and
	// unexpired used rows both survive untouched.
	DeleteExpiredCodes(ctx context.Context, now time.Time) error
}

// RefreshTokenStore persists refresh-token lineage rows. ByTokenHashForUpdate
// is the row-lock read a later plan's rotation/replay-kill logic needs
// (T-08-REFRESH-REPLAY).
type RefreshTokenStore interface {
	Create(ctx context.Context, rec *RefreshTokenRecord) error
	ByTokenHashForUpdate(ctx context.Context, tokenHash string) (*RefreshTokenRecord, error)
	// ByAPITokenIDForUpdate row-locks the refresh row currently linked to
	// apiTokenID, if any (08-06-PLAN.md D-08). It is the seam a
	// connected-app revoke uses to find the lineage to kill without
	// wristband inventing its own SQL join; a nil result (no linked
	// refresh row) is not an error.
	ByAPITokenIDForUpdate(ctx context.Context, apiTokenID uint) (*RefreshTokenRecord, error)
	// MarkRotated links a spent-by-rotation predecessor to its successor
	// (PHP OAuthCodeManager::rotateRefresh's `$record->rotated_to_id =
	// $successor->id`). The predecessor's own RevokedAt stays nil: a
	// rotated-but-not-yet-replayed row remains retrievable as replay
	// evidence (D-17); "already rotated" is signaled by RotatedToID, not
	// RevokedAt.
	MarkRotated(ctx context.Context, id uint, successorID uint) error
	// RevokeLineage stamps RevokedAt on startID and every row it was
	// rotated to (walking forward through RotatedToID), and revokes each
	// visited row's linked access token too (T-08-REFRESH-REPLAY). Rows
	// are not deleted: unexpired revoked rows stay as replay evidence
	// (D-17).
	RevokeLineage(ctx context.Context, startID uint) error
	// DeleteExpiredRefreshTokens removes refresh rows whose ExpiresAt is
	// before now (D-17). Revoked/rotated-but-unexpired rows are untouched
	// so replay detection and connected-apps history stay correct.
	DeleteExpiredRefreshTokens(ctx context.Context, now time.Time) error
}

// AccessTokenIssuer mints/revokes the app's ordinary personal access token
// (fonoteka: an inv_ token via ApiTokenManager) and stamps the owning OAuth
// client id.
type AccessTokenIssuer interface {
	Mint(ctx context.Context, userID uint, name string, scopes []string, expiresAt time.Time, collectionIDs []uint, clientID string) (IssuedToken, error)
	Revoke(ctx context.Context, tokenID uint) error
}

// Tx bundles every store/issuer onto one transaction-scoped handle so
// sweep+cap+create (this plan) and later code-exchange/refresh-rotation
// cannot straddle two transactions (08-RESEARCH.md Pattern 1).
type Tx interface {
	ClientStore
	AuthCodeStore
	RefreshTokenStore
	AccessTokenIssuer
}

// Backend opens one transaction-scoped Tx per call. The GORM adapter lives
// in fonoteka.go's classes/auth package (D-07): wristband never imports
// gorm.io/gorm or a fonoteka model.
type Backend interface {
	WithinTx(ctx context.Context, fn func(Tx) error) error
}