errors.go

package nexus

import (
	"errors"

	"github.com/xraph/nexus/pipeline/middlewares"
	"github.com/xraph/nexus/provider"
)

// ErrNotInitialized is returned by the engine's calls before
// [Gateway.Initialize] has finished.
var ErrNotInitialized = errors.New("nexus: gateway not initialized")

var (
	// Provider errors
	ErrProviderNotFound    = errors.New("nexus: provider not found")
	ErrProviderUnavailable = errors.New("nexus: provider unavailable")
	ErrModelNotSupported   = errors.New("nexus: model not supported by provider")
	ErrAllProvidersFailed  = errors.New("nexus: all providers failed")

	// Auth errors
	ErrUnauthorized  = errors.New("nexus: unauthorized")
	ErrAPIKeyInvalid = errors.New("nexus: invalid API key")
	ErrAPIKeyRevoked = errors.New("nexus: API key revoked")

	// Tenant errors
	ErrTenantNotFound = errors.New("nexus: tenant not found")
	ErrTenantDisabled = errors.New("nexus: tenant disabled")
	ErrQuotaExceeded  = errors.New("nexus: quota exceeded")
	ErrBudgetExceeded = errors.New("nexus: budget exceeded")

	// Rate limiting
	ErrRateLimited = errors.New("nexus: rate limited")

	// Guardrail errors
	ErrContentBlocked    = errors.New("nexus: content blocked by guardrail")
	ErrPIIDetected       = errors.New("nexus: PII detected in request")
	ErrInjectionDetected = errors.New("nexus: prompt injection detected")

	// Cache errors
	ErrCacheNotConfigured = errors.New("nexus: cache not configured")

	// Pipeline errors
	ErrPipelineAborted = errors.New("nexus: pipeline aborted")
	ErrCircuitOpen     = errors.New("nexus: circuit breaker open")

	// Context & tokens
	ErrContextOverflow     = errors.New("nexus: request exceeds context window")
	ErrTokenEstimateFailed = errors.New("nexus: token estimation failed")

	// Model aliases
	ErrAliasNotFound      = errors.New("nexus: model alias not found")
	ErrNoTargetsAvailable = errors.New("nexus: no alias targets available")

	// Extended thinking
	ErrThinkingNotSupported = errors.New("nexus: provider does not support extended thinking")

	// Batch
	ErrBatchTooLarge = errors.New("nexus: batch exceeds maximum size")
	ErrBatchNotFound = errors.New("nexus: batch job not found")

	// ErrModelUnpriced refuses a request for a model with no price at the
	// provider it was routed to (RefuseUnpriced). It is a *RefusalError with
	// code model_unpriced and status 400.
	ErrModelUnpriced = middlewares.ErrModelUnpriced

	// Credentials
	ErrCredentialExpired = errors.New("nexus: provider credential expired")
	// ErrCredentialNotFound is provider.ErrCredentialNotFound: a credential
	// provider returns it to serve a request with the provider's own key.
	ErrCredentialNotFound = provider.ErrCredentialNotFound
	// ErrCredentialUnavailable refuses a request whose credential could not
	// be resolved, or that the chosen provider cannot use
	// (WithCredentialProvider). It is a *RefusalError with code unavailable
	// and status 503; nothing is sent to the provider.
	ErrCredentialUnavailable = middlewares.ErrCredentialUnavailable
)