var ErrNotImplemented = errors.New("unimplemented")

type CPUTimer interface {
	// CPUTime returns a CPUTimes structure for
	// the host or some process.
	//
	// The User and System fields are guaranteed
	// to be populated for all platforms, and
	// for both hosts and processes.
	CPUTime() (CPUTimes, error)
}

type CPUTimes struct {
	User    time.Duration `json:"user"`
	System  time.Duration `json:"system"`
	Idle    time.Duration `json:"idle,omitempty"`
	IOWait  time.Duration `json:"iowait,omitempty"`
	IRQ     time.Duration `json:"irq,omitempty"`
	Nice    time.Duration `json:"nice,omitempty"`
	SoftIRQ time.Duration `json:"soft_irq,omitempty"`
	Steal   time.Duration `json:"steal,omitempty"`
}

type Capabilities interface {
	Capabilities() (*CapabilityInfo, error)
}

type CapabilityInfo struct {
	Inheritable []string `json:"inheritable"`
	Permitted   []string `json:"permitted"`
	Effective   []string `json:"effective"`
	Bounding    []string `json:"bounding"`
	Ambient     []string `json:"ambient"`
}

type Environment interface {
	Environment() (map[string]string, error)
}

type GoInfo struct {
	OS       string `json:"os"`
	Arch     string `json:"arch"`
	MaxProcs int    `json:"max_procs"`
	Version  string `json:"version"`
}

type Host interface {
	CPUTimer
	Info() HostInfo
	Memory() (*HostMemoryInfo, error)
}

type HostInfo struct {
	Architecture      string    `json:"architecture"`            // Hardware architecture (e.g. x86_64, arm, ppc, mips).
	BootTime          time.Time `json:"boot_time"`               // Host boot time.
	Containerized     *bool     `json:"containerized,omitempty"` // Is the process containerized.
	Hostname          string    `json:"name"`                    // Hostname
	IPs               []string  `json:"ip,omitempty"`            // List of all IPs.
	KernelVersion     string    `json:"kernel_version"`          // Kernel version.
	MACs              []string  `json:"mac"`                     // List of MAC addresses.
	OS                *OSInfo   `json:"os"`                      // OS information.
	Timezone          string    `json:"timezone"`                // System timezone.
	TimezoneOffsetSec int       `json:"timezone_offset_sec"`     // Timezone offset (seconds from UTC).
	UniqueID          string    `json:"id,omitempty"`            // Unique ID of the host (optional).
}

type HostMemoryInfo struct {
	Total        uint64            `json:"total_bytes"`         // Total physical memory.
	Used         uint64            `json:"used_bytes"`          // Total - Free
	Available    uint64            `json:"available_bytes"`     // Amount of memory available without swapping.
	Free         uint64            `json:"free_bytes"`          // Amount of memory not used by the system.
	VirtualTotal uint64            `json:"virtual_total_bytes"` // Total virtual memory.
	VirtualUsed  uint64            `json:"virtual_used_bytes"`  // VirtualTotal - VirtualFree
	VirtualFree  uint64            `json:"virtual_free_bytes"`  // Virtual memory that is not used.
	Metrics      map[string]uint64 `json:"raw,omitempty"`       // Other memory related metrics.
}

type LoadAverage interface {
	LoadAverage() LoadAverageInfo
}

type LoadAverageInfo struct {
	One     float64 `json:"one_min"`
	Five    float64 `json:"five_min"`
	Fifteen float64 `json:"fifteen_min"`
}

type MemoryInfo struct {
	Resident uint64            `json:"resident_bytes"`
	Virtual  uint64            `json:"virtual_bytes"`
	Metrics  map[string]uint64 `json:"raw,omitempty"` // Other memory related metrics.
}

type OSInfo struct {
	Family   string `json:"family"`             // OS Family (e.g. redhat, debian, freebsd, windows).
	Platform string `json:"platform"`           // OS platform (e.g. centos, ubuntu, windows).
	Name     string `json:"name"`               // OS Name (e.g. Mac OS X, CentOS).
	Version  string `json:"version"`            // OS version (e.g. 10.12.6).
	Major    int    `json:"major"`              // Major release version.
	Minor    int    `json:"minor"`              // Minor release version.
	Patch    int    `json:"patch"`              // Patch release version.
	Build    string `json:"build,omitempty"`    // Build (e.g. 16G1114).
	Codename string `json:"codename,omitempty"` // OS codename (e.g. jessie).
}

type OpenHandleCounter interface {
	OpenHandleCount() (int, error)
}

type OpenHandleEnumerator interface {
	OpenHandles() ([]string, error)
}

type Process interface {
	CPUTimer
	Info() (ProcessInfo, error)
	Memory() (MemoryInfo, error)
	User() (UserInfo, error)
	Parent() (Process, error)
	PID() int
}

type ProcessInfo struct {
	Name      string    `json:"name"`
	PID       int       `json:"pid"`
	PPID      int       `json:"ppid"`
	CWD       string    `json:"cwd"`
	Exe       string    `json:"exe"`
	Args      []string  `json:"args"`
	StartTime time.Time `json:"start_time"`
}

type Seccomp interface {
	Seccomp() (*SeccompInfo, error)
}

type SeccompInfo struct {
	Mode       string `json:"mode"`
	NoNewPrivs *bool  `json:"no_new_privs,omitempty"` // Added in kernel 4.10.
}

type UserInfo struct {
	// UID is the user ID.
	// On Linux and Darwin (macOS) this is the real user ID.
	// On Windows, this is the security identifier (SID) of the
	// user account of the process access token.
	UID string `json:"uid"`

	// On Linux and Darwin (macOS) this is the effective user ID.
	// On Windows, this is empty.
	EUID string `json:"euid"`

	// On Linux and Darwin (macOS) this is the saved user ID.
	// On Windows, this is empty.
	SUID string `json:"suid"`

	// GID is the primary group ID.
	// On Linux and Darwin (macOS) this is the real group ID.
	// On Windows, this is the security identifier (SID) of the
	// primary group of the process access token.
	GID string `json:"gid"`

	// On Linux and Darwin (macOS) this is the effective group ID.
	// On Windows, this is empty.
	EGID string `json:"egid"`

	// On Linux and Darwin (macOS) this is the saved group ID.
	// On Windows, this is empty.
	SGID string `json:"sgid"`
}