// Package keycloak adapts the Keycloak Admin API to the tenant-registry's
// language of "tenants" and "IT_ADMIN invites".
//
// The Adapter interface is the seam: tenant-registry handlers depend on
// it, never on the concrete HTTP client. Tests use Mock; production uses
// HTTPAdapter against the real KC at the configured base URL.
//
// Required Keycloak features (verified against KC 26):
//   - Organizations feature enabled in the realm (organizationsEnabled: true)
//   - Realm roles: BREAKPILOT_ADMIN, SUPPORT_ENGINEER, SALES_REP
//   - Group `/IT_ADMIN` (used as the org_role marker for invited users)
//
// All errors are wrapped with %w so callers can errors.Is them against
// ErrUnauthorized / ErrOrgConflict / ErrUserConflict.
package keycloak

import (
	"context"
	"errors"
)

// Sentinel errors.
var (
	ErrUnauthorized = errors.New("keycloak: admin auth failed")
	ErrOrgConflict  = errors.New("keycloak: organization already exists")
	ErrUserConflict = errors.New("keycloak: user already exists")
	ErrUnavailable  = errors.New("keycloak: unreachable")
)

// InviteInput captures the per-tenant onboarding event from POST /v1/tenants.
// The adapter creates a Keycloak organization, invites the IT_ADMIN, and
// stores the (TenantID, OrganizationID) link back in the caller's Tenant.
type InviteInput struct {
	TenantID   string // the tenant_registry id; stored as KC org attribute "tenant_id"
	Slug       string // becomes the KC org alias
	Name       string // human-readable org name
	AdminEmail string // IT_ADMIN to invite (required)
	AdminName  string // optional display name
}

// InviteResult is what the adapter produces. OrganizationID is what the
// tenant-registry stores so it can later assert tenants.id ↔ kc.org_id 1:1.
type InviteResult struct {
	OrganizationID string
	UserID         string
	// InviteURL is what the user clicks to set their password. In dev (no
	// Stalwart yet) we surface it in the response so testers can use it
	// directly. In prod it's emailed by Keycloak and we discard it.
	InviteURL string
}

// Claims is the tenant-scoped claim bundle the protocol-mapper would push
// into a JWT at token issuance. Returned by Adapter.ClaimsFor so the user-
// attributes can be refreshed on subscription change.
type Claims struct {
	TenantID     string   `json:"tenant_id"`
	TenantSlug   string   `json:"tenant_slug"`
	OrgRoles     []string `json:"org_roles"`
	Products     []string `json:"products"`
	Plan         string   `json:"plan"`
	TenantStatus string   `json:"tenant_status"`
}

// Adapter is the shape tenant-registry handlers code against. HTTPAdapter
// is the real one; Mock satisfies the same surface for tests.
type Adapter interface {
	// CreateOrgAndInvite is the M4.3 happy path. Atomic from the caller's
	// PoV: either both org+user land or neither does.
	CreateOrgAndInvite(ctx context.Context, in InviteInput) (*InviteResult, error)

	// SyncClaims pushes the current Claims into the user's Keycloak
	// attributes. Called whenever entitlements change (M4.2 catalog/trial
	// flows, M14.x cancel, M12.x trial transitions).
	SyncClaims(ctx context.Context, userID string, c Claims) error

	// Health pings the admin endpoint. Used by readyz and the cluster cold-
	// start sequence (INFRASTRUCTURE.md §10 scenario F).
	Health(ctx context.Context) error
}