provider

type Event struct {
	Type  EventType
	Delta string
	Usage Usage
	Err   error
}

type EventType int

type Factory func(cfg config.ProviderConfig) (Provider, error)

type Pricing struct {
	InputPer1M  float64
	OutputPer1M float64

	// CachedInputPer1M is the per-1M-token price for cached input tokens.
	// Zero means "same as InputPer1M" (no cache discount or not supported).
	CachedInputPer1M float64
}

type Provider interface {
	Name() string

	DefaultModel() string

	ContextWindow(model string) int

	EstimateTokens(text string) int

	Pricing(model string) Pricing

	Review(ctx context.Context, req Request) (Response, error)

	ReviewStream(ctx context.Context, req Request) (<-chan Event, error)

	TestConnection(ctx context.Context) error
}

type Request struct {
	Model        string
	SystemPrompt string
	UserPrompt   string
	Lang         string
	MaxTokens    int

	// ProviderOpts is an escape hatch (ADR-0001 risk #1) for features that
	// don't fit the common interface, e.g. Anthropic prompt caching or
	// OpenAI logprobs. Providers cast to their expected type; unknown values
	// are ignored.
	ProviderOpts any
}

type Response struct {
	Content string
	Model   string
	Usage   Usage
}

type Usage struct {
	InputTokens  int
	OutputTokens int

	// CachedInputTokens is the subset of InputTokens served from a provider-
	// side prompt cache (Anthropic ephemeral cache, OpenAI cached completions).
	// Zero if unknown or unsupported.
	CachedInputTokens int
}