captcha

type Alarms struct {
	// Counted is told every time the local fallback is handed out (the
	// metric); cause is "unreachable" or "misconfigured".
	Counted func(cause string)
	// Fallback is told once per window when the window's fallbacks pass the
	// threshold.
	Fallback func(count int, window time.Duration, cause, form string)
	// Misconfigured is told once an hour per reason.
	Misconfigured func(reason, form string)
}

type Challenge struct {
	Algorithm string `json:"algorithm"`
	Salt      string `json:"salt"`
	Hash      string `json:"hash"`
	Signature string `json:"signature"`
	MaxNumber int    `json:"maxnumber"`
}

type Config struct {
	Provider string
	SiteKey  string
	// Secret is the provider's secret, opened. Never leaves the server.
	Secret string
	// SecretUnreadable: the panel holds a secret that does not open (the
	// encryption key changed). It does not fall back to the environment:
	// a broken row must not be hidden.
	SecretUnreadable bool
	Forms            []string
	Fallback         string
	VerifyTimeout    time.Duration
	// Sources names, per field, the layer it came from.
	Sources map[string]string
}

type Consume func(signature string, ttl time.Duration) bool

type Fields struct {
	CaptchaToken        string `json:"captcha_token,omitempty"`
	CfTurnstileResponse string `json:"cf-turnstile-response,omitempty"`
	GRecaptchaResponse  string `json:"g-recaptcha-response,omitempty"`
	TurnstileToken      string `json:"turnstile_token,omitempty"`
	CaptchaLocal        string `json:"captcha_local,omitempty"`
}

type Invalid struct {
	Field string
	Min   int
	Max   int
}

type Local struct {
	// Key is the HMAC key. Every instance that checks a challenge must hold
	// the key that issued it.
	Key []byte
	// TTL is how long a challenge may be solved in; 0 = DefaultLocalTTL.
	TTL time.Duration
	// MaxNumber is the top of the range; 0 = DefaultMaxNumber.
	MaxNumber int
	// Now is the clock; nil = time.Now.
	Now func() time.Time
}

type LocalResult struct {
	OK bool
	// Reason is "ok" or the first step that refused.
	Reason string
	// Signature is the solution's signature, lowercase, when it was read.
	Signature string
	// Expires is the challenge's end, when it was read.
	Expires time.Time
}

type Marks interface {
	// AddCaptchaMark writes key until expires; false when a mark with that key
	// is still live at now (it was spent already).
	AddCaptchaMark(ctx context.Context, key string, expires, now int64) (bool, error)
	// PutCaptchaMark writes key until expires, over any mark it had.
	PutCaptchaMark(ctx context.Context, key string, expires int64) error
	// CaptchaMarkUntil answers the end of key's mark; ok false when none.
	CaptchaMarkUntil(ctx context.Context, key string) (int64, bool, error)
	// PruneCaptchaMarks deletes the marks that ended before now.
	PruneCaptchaMarks(ctx context.Context, now int64) (int64, error)
}

type MemoryMarks struct {
	// contains filtered or unexported fields
}

type Patch struct {
	Provider        *string   `json:"provider,omitempty"`
	SiteKey         *string   `json:"site_key,omitempty"`
	Secret          *string   `json:"secret,omitempty"`
	ClearSecret     bool      `json:"clear_secret,omitempty"`
	Forms           *[]string `json:"forms,omitempty"`
	ClearForms      bool      `json:"clear_forms,omitempty"`
	Fallback        *string   `json:"fallback,omitempty"`
	VerifyTimeoutMS *int      `json:"verify_timeout_ms,omitempty"`
}

type Probe struct {
	Reachable bool `json:"reachable"`
	// SecretOK: the provider took the secret (it refused only the probe's
	// token).
	SecretOK bool     `json:"secret_ok"`
	Codes    []string `json:"codes"`
	// Misconfigured names a configuration the probe could not use.
	Misconfigured string `json:"misconfigured,omitempty"`
	Cause         string `json:"cause,omitempty"`
}

type PublicConfig struct {
	Provider       string   `json:"provider"`
	SiteKey        *string  `json:"site_key"`
	Script         *string  `json:"script"`
	Fallback       string   `json:"fallback"`
	Forms          []string `json:"forms"`
	Misconfigured  bool     `json:"misconfigured"`
	FallbackActive bool     `json:"fallback_active"`
	LocalField     string   `json:"local_field"`
	TokenField     string   `json:"token_field"`
}

type Result struct {
	Status Status
	// Reason says why (invalid), what passed it ("provider" / "local"), or
	// what took the provider away (fallback, unavailable).
	Reason string
	// Challenge is the local challenge of a fallback.
	Challenge *Challenge
}

type SettingStore interface {
	GetSetting(ctx context.Context, key string) (string, error)
	UpsertSetting(ctx context.Context, key, value string) error
}

type Settings struct {
	Store SettingStore
	// Box seals the secret (FILEX_SECRET_KEY). Nil or keyless: the panel
	// cannot store one; CAPTCHA_SECRET still works.
	Box *secretbox.Box
	// Env reads the environment; nil = os.Getenv.
	Env func(string) string
	// TTL is how long a read is reused; 0 = 5 seconds, negative = not at all
	// (tests). Another instance's change is seen within it.
	TTL time.Duration
	// contains filtered or unexported fields
}

type Status string

type Stored struct {
	Provider        string   `json:"provider"`
	SiteKey         string   `json:"site_key"`
	HasSecret       bool     `json:"has_secret"`
	Forms           []string `json:"forms"`
	Fallback        string   `json:"fallback"`
	VerifyTimeoutMS int      `json:"verify_timeout_ms"`
}

type Verifier struct {
	Settings *Settings
	Marks    Marks
	// Client calls siteverify; nil = a plain client (each call has its own
	// timeout).
	Client *http.Client
	// Local issues and checks the fallback's challenges.
	Local *Local
	// PassKey signs the upload passes; nil = Local.Key.
	PassKey []byte
	Alarms  Alarms
	// Siteverify overrides a provider's address (tests).
	Siteverify map[string]string
	// Now is the clock; nil = time.Now.
	Now func() time.Time
	// contains filtered or unexported fields
}