package v2

import (
	"fmt"

	"edge-infra.dev/pkg/lib/kernel/drm"
	v1 "edge-infra.dev/pkg/sds/display/k8s/apis/v1"
	"edge-infra.dev/pkg/sds/lib/set"
)

const (
	// A display's card where the card could not be found.
	UnknownCard = "unknown"
	// A display which was disconnected during the V1 to V2 upgrade.
	DisconnectedPort = "disconnected"
)

// DisplayConfig defines the configuration for displays.
type DisplayConfig struct {
	// Maps monitor display-ports to display configurations.
	Displays Displays `json:"displays,omitempty"`
	// DPMS configuration
	DPMS *DPMS `json:"dpms,omitempty"`
	// Layout of the displays as slice, ordered left to right.
	Layout Layout `json:"layout,omitempty"`

	// The V1 spec following conversion from V1 to V2 by the
	// conversion webhook. This will be used by displayctl to
	// upgrade the spec to V2.
	//
	// This must only be set during conversion from V1 to V2
	// and cannot be set after the upgrade is complete.
	V1 *v1.DisplayConfig `json:"v1-displayConfig,omitempty"`
}

// The set of display-ports from both the displays and layout fields.
func (displayConfig *DisplayConfig) DisplayPorts() []DisplayPort {
	if displayConfig == nil {
		return []DisplayPort{}
	}
	dps := set.OrderedFromSlice(displayConfig.Displays.DisplayPorts())
	dps.Add(displayConfig.Layout...)
	return dps.ToSlice()
}

// Whether there is V1 spec which is yet to be upgraded.
func (displayConfig *DisplayConfig) HasV1() bool {
	return displayConfig != nil && displayConfig.V1 != nil
}

// Whether any of the displays were disconnected during V1 to V2
// upgrade and still requrie display-port identification.
func (displayConfig *DisplayConfig) HasDisconnected() bool {
	if displayConfig == nil {
		return false
	}
	for _, display := range displayConfig.Displays {
		if !display.IsConnected() {
			return true
		}
	}
	for _, dp := range displayConfig.Layout {
		if !dp.IsConnected() {
			return true
		}
	}
	return false
}

type Displays []Display

// Updates the display with matching display-port.
// Adds a new display if it is not yet present.
func (displays *Displays) UpdateDisplay(display Display) {
	if display.DisplayPort == "" {
		return
	}
	if currentDisplay := displays.FindByDisplayPort(display.DisplayPort); currentDisplay != nil {
		*currentDisplay = display
	} else {
		*displays = append(*displays, display)
	}
}

// The display with given display-port (nil if not found).
func (displays Displays) FindByDisplayPort(dp DisplayPort) *Display {
	for idx, display := range displays {
		if display.DisplayPort == dp {
			return &displays[idx]
		}
	}
	return nil
}

// The display with given MPID (nil if not found).
func (displays Displays) FindByMPID(mpid MPID) *Display {
	for idx, display := range displays {
		if display.MPID != nil && *display.MPID == mpid {
			return &displays[idx]
		}
	}
	return nil
}

// The primary display.
func (displays Displays) FindPrimary() *Display {
	for _, display := range displays {
		if display.IsPrimary() {
			return &display
		}
	}
	return nil
}

// Returns the displays display-ports.
func (displays Displays) DisplayPorts() []DisplayPort {
	dps := []DisplayPort{}
	for _, display := range displays {
		dps = append(dps, display.DisplayPort)
	}
	return dps
}

// Display configures a display's monitor and input devices.
type Display struct {
	// DisplayPort is the display card and physical port the
	// display is connected to, e.g. card0-DP1, card1-HDMI2 etc.
	//
	// This field is NOT optional.
	DisplayPort `json:"displayPort"`
	// Manufacturer and Product-Code ID, a unique identifier
	// for the display, i.e. "<manufacturer-ID>-<product-code>".
	//
	// It is NOT valid to configure this field in the
	// NodeDisplayConfig spec.
	*MPID `json:"mpid,omitempty"`
	// Primary indicates whether this is the primary display.
	*Primary `json:"primary,omitempty"`
	// Orientation of the display, e.g "left" or "inverted".
	Orientation *Orientation `json:"orientation,omitempty"`
	// Resolution is the current resolution of the display.
	*Resolution `json:"resolution,omitempty"`
	// SupportedResolutions are the valid resolutions the
	// display can be configured to use.
	//
	// It is NOT valid to configure this field in the
	// NodeDisplayConfig spec. The resolution of the display
	// can be configured via the Resolution field.
	SupportedResolutions []Resolution `json:"supportedResolutions,omitempty"`
	// InputDeviceMappings are the devices the display maps to.
	InputDeviceMappings []InputDeviceName `json:"inputDeviceMappings,omitempty"`
}

// +kubebuilder:validation:Pattern=`^(unknown|card\d)(-[A-Za-z0-9]+)+$`
//
// DisplayPort is the display card and physical port the
// display is connected to, e.g. card0-DP1, card1-HDMI-A-2 etc.
//
// If a card cannot be found for a display it will be marked
// unknown, e.g. unknown-DP2.
//
// Displays that were disconnected during upgrade from V1 to V2
// will be marked disconnected, e.g. unknown-disconnected-1.
type DisplayPort string

func NewDisplayPort(card, port string) DisplayPort {
	return DisplayPort(fmt.Sprintf("%s-%s", card, port))
}

func (dp *DisplayPort) String() string {
	if dp == nil {
		return ""
	}
	return string(*dp)
}

// Whether a display is connected.
//
// A display can be disconnected if it was not
// present during the V1 to V2 upgrade.
func (dp DisplayPort) IsConnected() bool {
	// if the display-port is not a valide connector name, it must be disconncted.
	err := drm.ValidateConnectorName(dp.String())
	return err == nil
}

// +kubebuilder:validation:Pattern=`^[A-Z]{3}-\d{1,5}$`
//
// Manufacturer and Product-Code ID, a unique identifier for
// the display, i.e. "<manufacturer-ID>-<product-code>".
type MPID string

func NewMPID(manufacturer string, productCode uint) MPID {
	return MPID(fmt.Sprintf("%s-%d", manufacturer, productCode))
}

func (mpid *MPID) String() string {
	if mpid == nil {
		return ""
	}
	return string(*mpid)
}

// Primary indicates whether a display is the primary display.
type Primary bool

func (display *Display) IsPrimary() bool {
	if display.Primary == nil {
		return false
	}
	return bool(*display.Primary)
}

func (display *Display) SetPrimary(primary bool) {
	display.Primary = (*Primary)(&primary)
}

// +kubebuilder:validation:Enum=normal;left;right;inverted
//
// Orientation is the displays orientation, e.g "normal",
// "left", "right" or "inverted".
type Orientation string

var (
	NormalOrientation   Orientation = "normal"
	LeftOrientation     Orientation = "left"
	RightOrientation    Orientation = "right"
	InvertedOrientation Orientation = "inverted"
)

func (o *Orientation) String() string {
	if o == nil {
		return ""
	}
	return string(*o)
}

// Resolution defines the resolution of a display.
type Resolution struct {
	// +kubebuilder:validation:Minimum=0
	//
	// Width of the display in pixels.
	Width int `json:"width"`
	// +kubebuilder:validation:Minimum=0
	//
	// Height of the display in pixels.
	Height int `json:"height"`
}

func (res *Resolution) String() string {
	if res == nil {
		return ""
	}
	return fmt.Sprintf("%dx%d", res.Width, res.Height)
}

// InputDeviceName is the name of an input device
type InputDeviceName string

func (name *InputDeviceName) String() string {
	if name == nil {
		return ""
	}
	return string(*name)
}

// DPMS describes the DPMS configuration for a display.
type DPMS struct {
	// Enabled indicates whether DPMS is enabled for the node.
	Enabled *bool `json:"enabled,omitempty"`
	// +kubebuilder:validation:Minimum=0
	//
	// BlankTime configures the number of seconds of inactivity
	// before reaching the blank phase of the screen saver.
	BlankTime *int `json:"blankTime,omitempty"`
	// +kubebuilder:validation:Minimum=0
	//
	// StandbyTime configures the number of seconds of inactivity
	// before reaching the standby phase of the DPMS mode.
	StandbyTime *int `json:"standybyTime,omitempty"`
	// +kubebuilder:validation:Minimum=0
	//
	// SuspendTime configures the number of seconds of inactivity
	// before reaching the suspend phase of the DPMS mode.
	SuspendTime *int `json:"suspendTime,omitempty"`
	// +kubebuilder:validation:Minimum=0
	//
	// OffTime configures the number of seconds of inactivity
	// before reaching the off phase of the DPMS mode.
	OffTime *int `json:"offTime,omitempty"`
}

// Layout describes the physical position of displays as their
// display-port's ordered left to right.
type Layout []DisplayPort