// Copyright 2026 certctl LLC. All rights reserved.
// SPDX-License-Identifier: BUSL-1.1

package domain

import (
	"encoding/json"
	"time"
)

// Issuer represents a certificate authority or ACME provider.
type Issuer struct {
	ID              string          `json:"id"`
	Name            string          `json:"name"`
	Type            IssuerType      `json:"type"`
	Config          json.RawMessage `json:"config"`
	EncryptedConfig []byte          `json:"-"` // AES-GCM encrypted full config (never exposed via API)
	Enabled         bool            `json:"enabled"`
	LastTestedAt    *time.Time      `json:"last_tested_at,omitempty"`
	TestStatus      string          `json:"test_status,omitempty"`
	Source          string          `json:"source,omitempty"`

	// HierarchyMode picks the per-issuer CA-hierarchy posture for the
	// local issuer adapter. "single" (default, pre-Rank-8 historical)
	// loads a pre-signed cert+key from disk via local.Config.CACertPath
	// / local.Config.CAKeyPath. "tree" activates first-class N-level
	// hierarchy management via the intermediate_cas table; chain
	// assembly walks parent_ca_id from the issuing leaf-CA up to the
	// root at issuance time. Empty string ≡ HierarchyModeSingle for
	// back-compat byte-identical behavior on unmigrated rows. Backed
	// by issuers.hierarchy_mode added in migration 000028.
	HierarchyMode string `json:"hierarchy_mode,omitempty"`

	CreatedAt time.Time `json:"created_at"`
	UpdatedAt time.Time `json:"updated_at"`
}

// DeploymentTarget represents a target system where certificates are deployed.
type DeploymentTarget struct {
	ID              string          `json:"id"`
	Name            string          `json:"name"`
	Type            TargetType      `json:"type"`
	AgentID         string          `json:"agent_id"`
	Config          json.RawMessage `json:"config"`
	EncryptedConfig []byte          `json:"-"` // AES-GCM encrypted full config (never exposed via API)
	Enabled         bool            `json:"enabled"`
	LastTestedAt    *time.Time      `json:"last_tested_at,omitempty"`
	TestStatus      string          `json:"test_status,omitempty"`
	Source          string          `json:"source,omitempty"`
	RetiredAt       *time.Time      `json:"retired_at,omitempty"`     // I-004: soft-retirement timestamp (nil = active)
	RetiredReason   *string         `json:"retired_reason,omitempty"` // I-004: reason captured at cascade retirement
	CreatedAt       time.Time       `json:"created_at"`
	UpdatedAt       time.Time       `json:"updated_at"`
}

// Agent represents an agent running on a target system.
type Agent struct {
	ID              string      `json:"id"`
	Name            string      `json:"name"`
	Hostname        string      `json:"hostname"`
	Status          AgentStatus `json:"status"`
	LastHeartbeatAt *time.Time  `json:"last_heartbeat_at,omitempty"`
	RegisteredAt    time.Time   `json:"registered_at"`
	// APIKeyHash is the SHA-256 of the agent's plaintext API key,
	// populated by service.RegisterAgent (`hashAPIKey(apiKey)`) and
	// consumed by repository.AgentRepository::GetByAPIKey at auth time.
	// It is server-internal: never serialized to clients, never echoed
	// via CLI / MCP / agent registration response, never logged.
	//
	// G-2 (P1): pre-G-2 the field was tagged `json:"api_key_hash"` and
	// shipped on every /api/v1/agents response (cat-s5-apikey_leak). Even
	// SHA-256 should not be shipped to clients — it gives an offline
	// brute-force target if API-key entropy is low (certctl doesn't enforce
	// a minimum on operator-supplied keys), and there is no business reason
	// for any client to ever receive it. Post-G-2 the JSON tag is "-" and
	// Agent.MarshalJSON below zeroes the field on a copy before delegating
	// to the default marshal — defense in depth so a future tag-revert by
	// refactor cannot reopen the leak. The DB column, repo SELECT/INSERT/
	// UPDATE paths, and service-side hashing are unchanged. See
	// docs/architecture.md ER diagram (which documents DB shape, not API
	// shape) and coverage-gap-audit-2026-04-24-v5/unified-audit.md
	// cat-s5-apikey_leak for the full closure rationale.
	APIKeyHash   string `json:"-"`
	OS           string `json:"os"`
	Architecture string `json:"architecture"`
	IPAddress    string `json:"ip_address"`
	Version      string `json:"version"`
	// I-004: soft-retirement fields. An agent with RetiredAt != nil is the
	// canonical "retired" state. The Status column remains as before (Online
	// / Offline / Degraded) and is preserved at retirement time as the
	// last-seen operational status; RetiredAt is the source of truth for
	// "should we filter this row from active listings?".
	RetiredAt     *time.Time `json:"retired_at,omitempty"`
	RetiredReason *string    `json:"retired_reason,omitempty"`
}

// MarshalJSON implements json.Marshaler. It explicitly zeros APIKeyHash
// before serialization to defense-in-depth the `json:"-"` tag above.
//
// G-2 (P1): pre-G-2 the field was tagged `json:"api_key_hash"` and
// shipped on every /api/v1/agents response (cat-s5-apikey_leak). Post-G-2
// the tag is "-" and this method enforces redaction even if the tag is
// reverted by a future refactor — the receiver is by-value so the
// APIKeyHash = "" assignment mutates only the marshal-time copy, never
// the caller's original. The type-alias trick (`type alias Agent`)
// breaks the recursive MarshalJSON call that would otherwise stack-
// overflow. Both *Agent and Agent receivers route through here because
// the json package looks the method up via reflect.Value, and a value
// receiver satisfies both kinds of pointer.
//
// Auditor's note for the next reader: do NOT remove this method even if
// the json:"-" tag stays. The CI guardrail at .github/workflows/ci.yml
// also blocks reintroduction at the tag site, but this method is the
// last line of defense for serialization paths that bypass struct tags
// (e.g., a future MarshalJSON on a parent struct that embeds Agent).
func (a Agent) MarshalJSON() ([]byte, error) {
	type alias Agent // breaks recursion: alias has no MarshalJSON method
	a.APIKeyHash = ""
	return json.Marshal(alias(a))
}

// IsRetired returns true when this agent has been soft-retired.
// I-004: callers that iterate active agents (stats dashboard, stale-offline
// sweeper, handler-facing list) must skip retired rows by default.
func (a *Agent) IsRetired() bool { return a != nil && a.RetiredAt != nil }

// AgentDependencyCounts captures the active downstream rows that would be
// affected by retiring an agent. Returned by the preflight pass on
// DELETE /api/v1/agents/{id}. Zero counts mean a clean soft-retire is safe;
// any non-zero count blocks a default retire with HTTP 409 and requires an
// explicit ?force=true&reason=... escape hatch from the operator.
type AgentDependencyCounts struct {
	ActiveTargets      int `json:"active_targets"`      // deployment_targets.agent_id=id AND retired_at IS NULL
	ActiveCertificates int `json:"active_certificates"` // certificates currently deployed via one of this agent's active targets
	PendingJobs        int `json:"pending_jobs"`        // jobs.agent_id=id AND status IN (Pending, AwaitingCSR, AwaitingApproval, Running)
}

// HasDependencies reports whether any preflight counter is non-zero.
func (d AgentDependencyCounts) HasDependencies() bool {
	return d.ActiveTargets > 0 || d.ActiveCertificates > 0 || d.PendingJobs > 0
}

// SentinelAgentIDs enumerates the four reserved agent identities that back
// non-agent discovery subsystems. These rows are created by cmd/server on
// startup and retiring them would orphan their subsystem — the network
// scanner and the three cloud secret-manager sources all key writes to
// these IDs via service.SentinelAgentID / service.SentinelAWSSecretsMgr /
// service.SentinelAzureKeyVault / service.SentinelGCPSecretMgr. The four
// literal IDs below MUST stay in lockstep with those service-package
// constants (see internal/service/network_scan.go line 23 and
// internal/service/cloud_discovery.go lines 14-16).
//
// The retirement service refuses them unconditionally — even with
// ?force=true — via ErrAgentIsSentinel. Living here (and not in the
// service package) lets handler, repository, and scheduler code filter
// them without importing service and creating a cycle.
var SentinelAgentIDs = []string{
	"server-scanner",
	"cloud-aws-sm",
	"cloud-azure-kv",
	"cloud-gcp-sm",
}

// IsSentinelAgent reports whether id matches one of the four reserved
// sentinel agent IDs. A linear scan is fine — the slice is length 4 and
// the check is rare (only on retirement attempts and sweeper filters).
func IsSentinelAgent(id string) bool {
	for _, s := range SentinelAgentIDs {
		if s == id {
			return true
		}
	}
	return false
}

// AgentMetadata contains runtime metadata reported by agents via heartbeat.
type AgentMetadata struct {
	OS           string `json:"os"`
	Architecture string `json:"architecture"`
	Hostname     string `json:"hostname"`
	IPAddress    string `json:"ip_address"`
	Version      string `json:"version"`
}

// AgentStatus represents the operational status of an agent.
type AgentStatus string

const (
	AgentStatusOnline   AgentStatus = "Online"
	AgentStatusOffline  AgentStatus = "Offline"
	AgentStatusDegraded AgentStatus = "Degraded"
)

// IssuerType represents the type of certificate authority.
type IssuerType string

const (
	IssuerTypeACME       IssuerType = "ACME"
	IssuerTypeGenericCA  IssuerType = "GenericCA"
	IssuerTypeStepCA     IssuerType = "StepCA"
	IssuerTypeOpenSSL    IssuerType = "OpenSSL"
	IssuerTypeVault      IssuerType = "VaultPKI"
	IssuerTypeDigiCert   IssuerType = "DigiCert"
	IssuerTypeSectigo    IssuerType = "Sectigo"
	IssuerTypeGoogleCAS  IssuerType = "GoogleCAS"
	IssuerTypeAWSACMPCA  IssuerType = "AWSACMPCA"
	IssuerTypeEntrust    IssuerType = "Entrust"
	IssuerTypeGlobalSign IssuerType = "GlobalSign"
	IssuerTypeEJBCA      IssuerType = "EJBCA"
)

// TargetType represents the type of deployment target.
type TargetType string

const (
	TargetTypeNGINX             TargetType = "NGINX"
	TargetTypeApache            TargetType = "Apache"
	TargetTypeHAProxy           TargetType = "HAProxy"
	TargetTypeF5                TargetType = "F5"
	TargetTypeIIS               TargetType = "IIS"
	TargetTypeTraefik           TargetType = "Traefik"
	TargetTypeCaddy             TargetType = "Caddy"
	TargetTypeEnvoy             TargetType = "Envoy"
	TargetTypePostfix           TargetType = "Postfix"
	TargetTypeDovecot           TargetType = "Dovecot"
	TargetTypeSSH               TargetType = "SSH"
	TargetTypeWinCertStore      TargetType = "WinCertStore"
	TargetTypeJavaKeystore      TargetType = "JavaKeystore"
	TargetTypeKubernetesSecrets TargetType = "KubernetesSecrets"
	// TargetTypeAWSACM deploys certificates to AWS Certificate Manager
	// (ACM) — the public AWS service that ALB / CloudFront / API
	// Gateway / App Runner consume by ARN. Rank 5 of the 2026-05-03
	// Infisical deep-research deliverable
	// (the project's deep-research deliverable, Part 5). See
	// docs/connectors.md "AWS Certificate Manager" section for the
	// operator playbook including minimum IAM policy + atomic-rollback
	// contract.
	TargetTypeAWSACM TargetType = "AWSACM"
	// TargetTypeAzureKeyVault deploys certificates to Azure Key Vault —
	// the Azure-managed cert store that Application Gateway / Front
	// Door / App Service / Container Apps consume by KID URI. Rank 5
	// of the 2026-05-03 Infisical deep-research deliverable. See
	// docs/connectors.md "Azure Key Vault" for the operator playbook
	// including minimum RBAC role + atomic-rollback + Azure-version
	// semantics.
	TargetTypeAzureKeyVault TargetType = "AzureKeyVault"
)