package model

import (
	"encoding/json"
	"errors"
	"fmt"
	"time"

	"github.com/grafana/grafana/pkg/components/simplejson"
	"github.com/grafana/grafana/pkg/kinds"
	"github.com/grafana/grafana/pkg/kinds/librarypanel"
	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)

type LibraryConnectionKind int

const (
	Dashboard LibraryConnectionKind = iota + 1
)

// LibraryElement is the model for library element definitions.
type LibraryElement struct {
	ID          int64  `xorm:"pk autoincr 'id'"`
	OrgID       int64  `xorm:"org_id"`
	FolderID    int64  `xorm:"folder_id"`
	UID         string `xorm:"uid"`
	Name        string
	Kind        int64
	Type        string
	Description string
	Model       json.RawMessage
	Version     int64

	Created time.Time
	Updated time.Time

	CreatedBy int64
	UpdatedBy int64
}

// LibraryElementWithMeta is the model used to retrieve entities with additional meta information.
type LibraryElementWithMeta struct {
	ID          int64  `xorm:"pk autoincr 'id'"`
	OrgID       int64  `xorm:"org_id"`
	FolderID    int64  `xorm:"folder_id"`
	UID         string `xorm:"uid"`
	Name        string
	Kind        int64
	Type        string
	Description string
	Model       json.RawMessage
	Version     int64

	Created time.Time
	Updated time.Time

	FolderName          string
	FolderUID           string `xorm:"folder_uid"`
	ConnectedDashboards int64
	CreatedBy           int64
	UpdatedBy           int64
	CreatedByName       string
	CreatedByEmail      string
	UpdatedByName       string
	UpdatedByEmail      string
}

// LibraryElementDTO is the frontend DTO for entities.
type LibraryElementDTO struct {
	ID            int64                 `json:"id"`
	OrgID         int64                 `json:"orgId"`
	FolderID      int64                 `json:"folderId"`
	FolderUID     string                `json:"folderUid"`
	UID           string                `json:"uid"`
	Name          string                `json:"name"`
	Kind          int64                 `json:"kind"`
	Type          string                `json:"type"`
	Description   string                `json:"description"`
	Model         json.RawMessage       `json:"model"`
	Version       int64                 `json:"version"`
	Meta          LibraryElementDTOMeta `json:"meta"`
	SchemaVersion int64                 `json:"schemaVersion,omitempty"`
}

func (dto *LibraryElementDTO) ToResource() kinds.GrafanaResource[simplejson.Json, simplejson.Json] {
	body := &simplejson.Json{}
	_ = body.FromDB(dto.Model)
	parent := librarypanel.NewK8sResource(dto.UID, nil)
	res := kinds.GrafanaResource[simplejson.Json, simplejson.Json]{
		Kind:       parent.Kind,
		APIVersion: parent.APIVersion,
		Metadata: kinds.GrafanaResourceMetadata{
			Name:              dto.UID,
			Annotations:       make(map[string]string),
			Labels:            make(map[string]string),
			ResourceVersion:   fmt.Sprintf("%d", dto.Version),
			CreationTimestamp: v1.NewTime(dto.Meta.Created),
		},
		Spec: body,
	}

	if dto.FolderUID != "" {
		res.Metadata.SetFolder(dto.FolderUID)
	}
	res.Metadata.SetCreatedBy(fmt.Sprintf("user:%d", dto.Meta.CreatedBy.Id))
	res.Metadata.SetUpdatedBy(fmt.Sprintf("user:%d", dto.Meta.UpdatedBy.Id))
	res.Metadata.SetUpdatedTimestamp(&dto.Meta.Updated)
	return res
}

// LibraryElementSearchResult is the search result for entities.
type LibraryElementSearchResult struct {
	TotalCount int64               `json:"totalCount"`
	Elements   []LibraryElementDTO `json:"elements"`
	Page       int                 `json:"page"`
	PerPage    int                 `json:"perPage"`
}

// LibraryElementDTOMeta is the meta information for LibraryElementDTO.
type LibraryElementDTOMeta struct {
	FolderName          string `json:"folderName"`
	FolderUID           string `json:"folderUid"`
	ConnectedDashboards int64  `json:"connectedDashboards"`

	Created time.Time `json:"created"`
	Updated time.Time `json:"updated"`

	CreatedBy librarypanel.LibraryElementDTOMetaUser `json:"createdBy"`
	UpdatedBy librarypanel.LibraryElementDTOMetaUser `json:"updatedBy"`
}

// libraryElementConnection is the model for library element connections.
type LibraryElementConnection struct {
	ID           int64 `xorm:"pk autoincr 'id'"`
	ElementID    int64 `xorm:"element_id"`
	Kind         int64 `xorm:"kind"`
	ConnectionID int64 `xorm:"connection_id"`
	Created      time.Time
	CreatedBy    int64
}

// libraryElementConnectionWithMeta is the model for library element connections with meta.
type LibraryElementConnectionWithMeta struct {
	ID             int64  `xorm:"pk autoincr 'id'"`
	ElementID      int64  `xorm:"element_id"`
	Kind           int64  `xorm:"kind"`
	ConnectionID   int64  `xorm:"connection_id"`
	ConnectionUID  string `xorm:"connection_uid"`
	Created        time.Time
	CreatedBy      int64
	CreatedByName  string
	CreatedByEmail string
}

// LibraryElementConnectionDTO is the frontend DTO for element connections.
type LibraryElementConnectionDTO struct {
	ID            int64                                  `json:"id"`
	Kind          int64                                  `json:"kind"`
	ElementID     int64                                  `json:"elementId"`
	ConnectionID  int64                                  `json:"connectionId"`
	ConnectionUID string                                 `json:"connectionUid"`
	Created       time.Time                              `json:"created"`
	CreatedBy     librarypanel.LibraryElementDTOMetaUser `json:"createdBy"`
}

var (
	// errLibraryElementAlreadyExists is an error for when the user tries to add a library element that already exists.
	ErrLibraryElementAlreadyExists = errors.New("library element with that name or UID already exists")
	// ErrLibraryElementNotFound is an error for when a library element can't be found.
	ErrLibraryElementNotFound = errors.New("library element could not be found")
	// errLibraryElementDashboardNotFound is an error for when a library element connection can't be found.
	ErrLibraryElementDashboardNotFound = errors.New("library element connection could not be found")
	// ErrLibraryElementHasConnections is an error for when an user deletes a library element that is connected.
	ErrLibraryElementHasConnections = errors.New("the library element has connections")
	// errLibraryElementVersionMismatch is an error for when a library element has been changed by someone else.
	ErrLibraryElementVersionMismatch = errors.New("the library element has been changed by someone else")
	// errLibraryElementUnSupportedElementKind is an error for when the kind is unsupported.
	ErrLibraryElementUnSupportedElementKind = errors.New("the element kind is not supported")
	// ErrFolderHasConnectedLibraryElements is an error for when a user deletes a folder that contains connected library elements.
	ErrFolderHasConnectedLibraryElements = errors.New("folder contains library elements that are linked in use")
	// errLibraryElementInvalidUID is an error for when the uid of a library element is invalid
	ErrLibraryElementInvalidUID = errors.New("uid contains illegal characters")
	// errLibraryElementUIDTooLong is an error for when the uid of a library element is invalid
	ErrLibraryElementUIDTooLong = errors.New("uid too long, max 40 characters")
)

// Commands

// CreateLibraryElementCommand is the command for adding a LibraryElement
// swagger:model
type CreateLibraryElementCommand struct {
	// ID of the folder where the library element is stored.
	FolderID int64 `json:"folderId"`
	// UID of the folder where the library element is stored.
	FolderUID *string `json:"folderUid"`
	// Name of the library element.
	Name string `json:"name"`
	// The JSON model for the library element.
	// swagger:type object
	Model json.RawMessage `json:"model"`
	// Kind of element to create, Use 1 for library panels or 2 for c.
	// Description:
	// * 1 - library panels
	// * 2 - library variables
	// Enum: 1,2
	Kind int64 `json:"kind" binding:"Required"`
	// required: false
	UID string `json:"uid"`
}

// PatchLibraryElementCommand is the command for patching a LibraryElement
type PatchLibraryElementCommand struct {
	// ID of the folder where the library element is stored.
	FolderID int64 `json:"folderId" binding:"Default(-1)"`
	// UID of the folder where the library element is stored.
	FolderUID *string `json:"folderUid"`
	// Name of the library element.
	Name string `json:"name"`
	// The JSON model for the library element.
	Model json.RawMessage `json:"model,omitempty"`
	// Kind of element to create, Use 1 for library panels or 2 for c.
	// Description:
	// * 1 - library panels
	// * 2 - library variables
	// Enum: 1,2
	Kind int64 `json:"kind" binding:"Required"`
	// Version of the library element you are updating.
	Version int64 `json:"version" binding:"Required"`
	// required: false
	UID string `json:"uid"`
}

// GetLibraryElementCommand is the command for getting a library element.
type GetLibraryElementCommand struct {
	FolderName string
	FolderID   int64
	UID        string
}

// SearchLibraryElementsQuery is the query used for searching for Elements
type SearchLibraryElementsQuery struct {
	PerPage          int
	Page             int
	SearchString     string
	SortDirection    string
	Kind             int
	TypeFilter       string
	ExcludeUID       string
	FolderFilter     string
	FolderFilterUIDs string
}

// LibraryElementResponse is a response struct for LibraryElementDTO.
type LibraryElementResponse struct {
	Result LibraryElementDTO `json:"result"`
}

// LibraryElementSearchResponse is a response struct for LibraryElementSearchResult.
type LibraryElementSearchResponse struct {
	Result LibraryElementSearchResult `json:"result"`
}

// LibraryElementArrayResponse is a response struct for an array of LibraryElementDTO.
type LibraryElementArrayResponse struct {
	Result []LibraryElementDTO `json:"result"`
}

// LibraryElementConnectionsResponse is a response struct for an array of LibraryElementConnectionDTO.
type LibraryElementConnectionsResponse struct {
	Result []LibraryElementConnectionDTO `json:"result"`
}

// DeleteLibraryElementResponse is the response struct for deleting a library element.
type DeleteLibraryElementResponse struct {
	ID      int64  `json:"id"`
	Message string `json:"message"`
}

// LibraryElementKind is used for the kind of library element
type LibraryElementKind int

const (
	// PanelElement is used for library elements that are of the Panel kind
	PanelElement LibraryElementKind = iota + 1
	// VariableElement is used for library elements that are of the Variable kind
	VariableElement
)

const LibraryElementConnectionTableName = "library_element_connection"