package webutility

  import "gopkg.in/rana/ora.v4"

  
  type ListOptions struct {
  	GlobalFilter  bool   `json:"globalFilter"`
  	LocalFilters  bool   `json:"localFilters"`
  	RemoteFilters bool   `json:"remoteFilters"`
  	Pagination    bool   `json:"pagination"`
  	PageSize      uint64 `json:"pageSize"`
  	Pivot         bool   `json:"pivot"`
  	Detail        bool   `json:"detail"`

  	Total         bool   `json:"total"`

  }
  
  type ListFilter struct {

  	Position       uint32   `json:"-"`

  	ObjectType     string   `json:"-"`
  	FiltersField   string   `json:"filtersField"`
  	DefaultValues  string   `json:"defaultValues"`
  	FiltersType    string   `json:"filtersType"`
  	FiltersLabel   string   `json:"filtersLabel"`
  	DropdownConfig Dropdown `json:"dropdownConfig"`
  }
  
  type Dropdown struct {
  	ObjectType   string `json:"objectType"`
  	FiltersField string `json:"filtersField"`

  	IDField      string `json:"idField"`

  	LabelField   string `json:"labelField"`

  }
  
  type ListGraph struct {
  	ObjectType string `json:"objectType"`

  	X          string `json:"xField"`
  	Y          string `json:"yField"`

  	GroupField string `json:"groupField"`

  	Label      string `json:"label"`

  }
  
  type ListActions struct {
  	Create bool `json:"create"`
  	Update bool `json:"update"`
  	Delete bool `json:"delete"`
  	Export bool `json:"export"`
  	Print  bool `json:"print"`
  	Graph  bool `json:"graph"`
  }

  type ListNavNode struct {

  	ObjectType        string `json:"objectType"`
  	LabelField        string `json:"label"`
  	Icon              string `json:"icon"`
  	ParentObjectType  string `json:"parentObjectType"`
  	ParentIDField     string `json:"parentIdField"`
  	ParentFilterField string `json:"parentFilterField"`

  }
  
  type ListParentNode struct {
  	ObjectType  string `json:"objectType"`
  	LabelField  string `json:"labelField"`
  	FilterField string `json:"filterField"`
  }
  
  type ListPivot struct {
  	ObjectType    string `json:"objectType"`
  	GroupField    string `json:"groupField"`
  	DistinctField string `json:"distinctField"`
  	Value         string `json:"valueField"`
  }
  
  type ListDetails struct {
  	ObjectType        string `json:"objectType"`
  	ParentObjectType  string `json:"parentObjectType"`
  	ParentFilterField string `json:"parentFilterField"`
  	SingleDetail      bool   `json:"singleDetail"`
  }
  
  type ListConfig struct {
  	ObjectType string           `json:"objectType"`
  	Title      string           `json:"title"`
  	LazyLoad   bool             `json:"lazyLoad"`
  	InlineEdit bool             `json:"inlineEdit"`
  	Options    ListOptions      `json:"options"`
  	Filters    []ListFilter     `json:"defaultFilters"`
  	Graphs     []ListGraph      `json:"graphs"`
  	Actions    ListActions      `json:"actions"`
  	Parent     []ListParentNode `json:"parent"`

  	Navigation []ListNavNode    `json:"navigation"`

  	Pivots     []ListPivot      `json:"pivots"`
  	Details    ListDetails      `json:"details"`
  }

  // GetListConfig returns list configuration for the provided object type for the front-end application
  // or an error if it fails.

  func GetListConfig(db *ora.Ses, objType string) (ListConfig, error) {

  	resp := newDefaultList(objType)

  	var err error
  
  	err = setListParams(db, &resp, objType)

  	resp.Navigation, err = getListNavigation(db, objType)

  	resp.Actions, err = getListActions(db, objType)
  	resp.Filters, err = getListFilters(db, objType)
  	resp.Options, err = getListOptions(db, objType)
  	resp.Parent, err = getListParent(db, objType)
  	resp.Graphs, err = getListGraph(db, objType)
  	resp.Pivots, err = getListPivot(db, objType)
  	resp.Details, err = getListDetails(db, objType)
  
  	if err != nil {
  		return ListConfig{}, err
  	}
  
  	return resp, nil
  }

  // GetListConfigObjectIDField takes in database connection and an object type and it returns the
  // ID field name for the provided object type.

  func GetListConfigObjectIDField(db *ora.Ses, otype string) string {

  	var resp string
  	var err error
  	var stmt *ora.Stmt
  
  	stmt, err = db.Prep(`SELECT
  		ID_FIELD
  		FROM LIST_CONFIG_ID_FIELD

  		WHERE OBJECT_TYPE = '`+otype+`'`,

  		ora.S)
  
  	defer stmt.Close()
  
  	if err != nil {
  		return ""
  	}
  
  	rset, err := stmt.Qry()
  	if rset.Next() {
  		resp = rset.Row[0].(string)
  	}

  	if rset.Err() != nil {

  		return ""
  	}
  
  	return resp
  }

  // newDefaultList returns default configuration for the provided object type.

  func newDefaultList(objType string) ListConfig {

  	list := ListConfig{
  		ObjectType: objType,

  		Title:      objType,
  		LazyLoad:   false,

  		Options: ListOptions{

  			GlobalFilter:  true,
  			LocalFilters:  true,

  			RemoteFilters: false,

  			Pagination:    true,
  			PageSize:      20,

  		},
  		Filters: nil,
  		Actions: ListActions{
  			Create: false,
  			Update: false,
  			Delete: false,
  			Export: false,

  			Print:  false,
  			Graph:  false,

  		},

  		Parent:     nil,

  		Navigation: nil,

  	}
  
  	return list
  }

  // setListParams sets the default parameters of the provided configuration list for the provided object type.

  func setListParams(db *ora.Ses, list *ListConfig, objType string) error {
  	var err error
  	var stmt *ora.Stmt

  	query := `SELECT

  		OBJECT_TYPE, TITLE, LAZY_LOAD, INLINE_EDIT
  		FROM LIST_CONFIG
  		WHERE OBJECT_TYPE = '` + objType + `'`
  
  	stmt, err = db.Prep(query, ora.S, ora.S, ora.U32, ora.U32)
  	if err != nil {
  		return err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return err
  	}
  	if rset.Next() {
  		otype := rset.Row[0].(string)
  		if otype != "" {
  			list.ObjectType = otype
  		}
  
  		title := rset.Row[1].(string)
  		if title != "" {
  			list.Title = title
  		}
  		list.LazyLoad = rset.Row[2].(uint32) != 0
  		list.InlineEdit = rset.Row[3].(uint32) != 0
  	}

  	if rset.Err() != nil {
  		return rset.Err()

  	}
  	return nil
  }

  // getListNavigation returns list navigation node slice for the provided objectType.

  func getListNavigation(db *ora.Ses, listObjType string) ([]ListNavNode, error) {

  	resp := make([]ListNavNode, 0)

  	var err error
  	var stmt *ora.Stmt

  	query := `SELECT
  		a.OBJECT_TYPE, a.PARENT_OBJECT_TYPE, a.LABEL, a.ICON, a.PARENT_FILTER_FIELD, b.PARENT_ID_FIELD, b.RB
  		FROM LIST_CONFIG_NAVIGATION b

  		JOIN LIST_CONFIG_CHILD a ON b.PARENT_CHILD_ID = a.PARENT_CHILD_ID

  		WHERE b.LIST_OBJECT_TYPE = '` + listObjType + `'

  		ORDER BY b.RB ASC`

  	stmt, err = db.Prep(query, ora.S, ora.S, ora.S, ora.S, ora.S)

  	if err != nil {
  		return resp, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return resp, err
  	}
  	for rset.Next() {

  		resp = append(resp, ListNavNode{

  			ObjectType:        rset.Row[0].(string),
  			ParentObjectType:  rset.Row[1].(string),
  			LabelField:        rset.Row[2].(string),
  			Icon:              rset.Row[3].(string),

  			ParentFilterField: rset.Row[4].(string),

  			ParentIDField:     rset.Row[5].(string),

  			// RB is ignored

  		})
  	}

  	if rset.Err() != nil {
  		return nil, rset.Err()

  	}
  
  	return resp, nil
  }

  // getListActions returns list actions for the provided object type.

  func getListActions(db *ora.Ses, objType string) (ListActions, error) {
  	var resp ListActions
  	var err error
  	var stmt *ora.Stmt

  	query := `SELECT

  		ACTION_CREATE, ACTION_UPDATE, ACTION_DELETE, ACTION_EXPORT,
  		ACTION_PRINT, ACTION_GRAPH
  		FROM LIST_CONFIG
  		WHERE OBJECT_TYPE = '` + objType + `'`
  
  	stmt, err = db.Prep(query, ora.U32, ora.U32, ora.U32, ora.U32,
  		ora.U32, ora.U32)
  	if err != nil {
  		return ListActions{}, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return ListActions{}, err
  	}
  	if rset.Next() {
  		resp.Create = rset.Row[0].(uint32) != 0
  		resp.Update = rset.Row[1].(uint32) != 0
  		resp.Delete = rset.Row[2].(uint32) != 0
  		resp.Export = rset.Row[3].(uint32) != 0
  		resp.Print = rset.Row[4].(uint32) != 0
  		resp.Graph = rset.Row[5].(uint32) != 0
  	}

  	if rset.Err() != nil {
  		return ListActions{}, rset.Err()

  	}
  	return resp, nil
  }

  // getListFiters returns list filter slice for the provided object type.

  func getListFilters(db *ora.Ses, objType string) ([]ListFilter, error) {
  	resp := make([]ListFilter, 0)

  	filtersFields, err := getFilterFieldsAndPosition(db, objType)

  	if err != nil {
  		return nil, err
  	}

  	for field, pos := range filtersFields {

  		filters, _ := getFiltersByFilterField(db, field)
  		for _, filter := range filters {

  			var f ListFilter

  			f.Position = pos

  			f.ObjectType = objType
  			f.FiltersField = field
  			f.DefaultValues = filter.DefaultValues
  			f.FiltersLabel = filter.Label
  			f.FiltersType = filter.Type
  			if filter.Type == "dropdown" {
  				f.DropdownConfig, err = getFilterDropdownConfig(db, field)
  				if err != nil {
  					return nil, err
  				}
  			}
  			resp = append(resp, f)

  		}
  	}

  	sortFilters(resp)

  	return resp, nil
  }

  // getFilterFieldsAndPosition returns a map of filter fields and their respective position in the menu.

  func getFilterFieldsAndPosition(db *ora.Ses, objType string) (map[string]uint32, error) {
  	filtersField := make(map[string]uint32, 0)

  	var err error
  	var stmt *ora.Stmt
  	query := `SELECT 

  		FILTERS_FIELD, RB

  		FROM LIST_CONFIG_FILTERS
  		WHERE OBJECT_TYPE = '` + objType + `'`

  	stmt, err = db.Prep(query, ora.S, ora.U32)

  	if err != nil {
  		return nil, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return nil, err
  	}
  	for rset.Next() {

  		filtersField[rset.Row[0].(string)] = rset.Row[1].(uint32)

  	}

  	if rset.Err() != nil {
  		return nil, rset.Err()

  	}
  	return filtersField, nil
  }

  type _filter struct {

  	DefaultValues string

  	Label         string
  	Type          string

  }

  // getFiltersByFilterField returns filter slice for the provided filter field.

  func getFiltersByFilterField(db *ora.Ses, filtersField string) ([]_filter, error) {
  	resp := make([]_filter, 0)

  	var err error
  	var stmt *ora.Stmt
  	query := `SELECT 
  		FILTERS_TYPE, FILTERS_LABEL, DEFAULT_VALUES
  		FROM LIST_FILTERS_FIELD
  		WHERE FILTERS_FIELD = '` + filtersField + `'`
  
  	stmt, err = db.Prep(query, ora.S, ora.S, ora.S)
  	if err != nil {
  		return resp, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return resp, err
  	}
  	for rset.Next() {

  		resp = append(resp, _filter{

  			Type:          rset.Row[0].(string),
  			Label:         rset.Row[1].(string),

  			DefaultValues: rset.Row[2].(string),
  		})
  	}

  	if rset.Err() != nil {
  		return resp, rset.Err()

  	}
  	return resp, nil
  }

  // getFilterDropdownConfig returns dropdown menu for the provided filter field.

  func getFilterDropdownConfig(db *ora.Ses, filtersField string) (Dropdown, error) {
  	var resp Dropdown
  	var err error
  	var stmt *ora.Stmt
  	query := `SELECT 
  		FILTERS_FIELD, OBJECT_TYPE, ID_FIELD, LABEL_FIELD
  		FROM LIST_DROPDOWN_FILTER
  		WHERE FILTERS_FIELD = '` + filtersField + `'`
  
  	stmt, err = db.Prep(query, ora.S, ora.S, ora.S, ora.S)
  	if err != nil {
  		return resp, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return resp, err
  	}
  	if rset.Next() {
  		resp.FiltersField = rset.Row[0].(string)
  		resp.ObjectType = rset.Row[1].(string)

  		resp.IDField = rset.Row[2].(string)

  		resp.LabelField = rset.Row[3].(string)
  	}

  	if rset.Err() != nil {
  		return resp, rset.Err()

  	}
  	return resp, nil
  }

  // sortFilters bubble sorts provided filters slice by position field.

  func sortFilters(filters []ListFilter) {
  	done := false
  	var temp ListFilter
  	for !done {
  		done = true

  		for i := 0; i < len(filters)-1; i++ {

  			if filters[i].Position > filters[i+1].Position {
  				done = false
  				temp = filters[i]
  				filters[i] = filters[i+1]
  				filters[i+1] = temp
  			}
  		}
  	}
  }

  // getListGraph return list graph slice for the provided object type.

  func getListGraph(db *ora.Ses, objType string) ([]ListGraph, error) {
  	resp := make([]ListGraph, 0)
  	var err error
  	var stmt *ora.Stmt
  	query := `SELECT 
  		OBJECT_TYPE, X_FIELD, Y_FIELD, GROUP_FIELD, LABEL
  		FROM LIST_GRAPHS
  		WHERE OBJECT_TYPE = '` + objType + `'`
  
  	stmt, err = db.Prep(query, ora.S, ora.S, ora.S, ora.S)
  	if err != nil {
  		return resp, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return resp, err
  	}
  	for rset.Next() {
  		resp = append(resp, ListGraph{
  			ObjectType: rset.Row[0].(string),

  			X:          rset.Row[1].(string),
  			Y:          rset.Row[2].(string),

  			GroupField: rset.Row[3].(string),

  			Label:      rset.Row[4].(string),

  		})
  	}

  	if rset.Err() != nil {
  		return resp, rset.Err()

  	}
  	return resp, nil
  }

  // getListOptions returns list options for the provided object type.

  func getListOptions(db *ora.Ses, objType string) (ListOptions, error) {
  	var resp ListOptions
  	var err error
  	var stmt *ora.Stmt
  	query := `SELECT 
  		GLOBAL_FILTER, LOCAL_FILTER, REMOTE_FILTER, PAGINATION, 

  		PAGE_SIZE, PIVOT, DETAIL, TOTAL

  		FROM LIST_CONFIG
  		WHERE OBJECT_TYPE = '` + objType + `'`
  
  	stmt, err = db.Prep(query, ora.U32, ora.U32, ora.U32, ora.U32,

  		ora.U64, ora.U64, ora.U32, ora.U32)

  	if err != nil {
  		return ListOptions{}, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return ListOptions{}, err
  	}
  	if rset.Next() {
  		resp.GlobalFilter = rset.Row[0].(uint32) != 0
  		resp.LocalFilters = rset.Row[1].(uint32) != 0
  		resp.RemoteFilters = rset.Row[2].(uint32) != 0
  		resp.Pagination = rset.Row[3].(uint32) != 0
  		resp.PageSize = rset.Row[4].(uint64)
  		resp.Pivot = rset.Row[5].(uint64) != 0
  		resp.Detail = rset.Row[6].(uint32) != 0

  		resp.Total = rset.Row[7].(uint32) != 0

  	}

  	if rset.Err() != nil {
  		return ListOptions{}, rset.Err()

  	}
  	return resp, nil
  }

  // getListParent returns list parent node slice for the provided object type.

  func getListParent(db *ora.Ses, objType string) ([]ListParentNode, error) {
  	resp := make([]ListParentNode, 0)
  	var err error
  	var stmt *ora.Stmt
  	query := `SELECT 
  		PARENT_OBJECT_TYPE, PARENT_LABEL_FIELD, PARENT_FILTER_FIELD
  		FROM LIST_CONFIG_CHILD
  		WHERE OBJECT_TYPE = '` + objType + `'`
  
  	stmt, err = db.Prep(query, ora.S, ora.S, ora.S)
  	if err != nil {
  		return resp, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return resp, err
  	}
  	for rset.Next() {
  		resp = append(resp, ListParentNode{

  			ObjectType:  rset.Row[0].(string),
  			LabelField:  rset.Row[1].(string),

  			FilterField: rset.Row[2].(string),
  		})
  	}

  	if rset.Err() != nil {
  		return nil, rset.Err()

  	}
  
  	return resp, nil
  }

  // getListPivot list pivot slice for the provided object type.

  func getListPivot(db *ora.Ses, objType string) ([]ListPivot, error) {
  	resp := make([]ListPivot, 0)
  	var err error
  	var stmt *ora.Stmt
  	query := `SELECT 
  		OBJECT_TYPE, GROUP_FIELD, DISTINCT_FIELD, VALUE_FIELD
  		FROM LIST_PIVOTS
  		WHERE OBJECT_TYPE = '` + objType + `'`
  
  	stmt, err = db.Prep(query, ora.S, ora.S, ora.S, ora.S)
  	if err != nil {
  		return resp, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return resp, err
  	}
  	for rset.Next() {
  		resp = append(resp, ListPivot{

  			ObjectType:    rset.Row[0].(string),
  			GroupField:    rset.Row[1].(string),

  			DistinctField: rset.Row[2].(string),

  			Value:         rset.Row[3].(string),

  		})
  	}

  	if rset.Err() != nil {
  		return nil, rset.Err()

  	}
  
  	return resp, nil
  }

  // getListDetails returns list details for the provided object type.

  func getListDetails(db *ora.Ses, objType string) (ListDetails, error) {
  	var resp ListDetails
  	var err error
  	var stmt *ora.Stmt
  	query := `SELECT 
  		OBJECT_TYPE, PARENT_OBJECT_TYPE, PARENT_FILTER_FIELD, SINGLE_DETAIL
  		FROM LIST_CONFIG_DETAIL
  		WHERE PARENT_OBJECT_TYPE = '` + objType + `'`
  
  	stmt, err = db.Prep(query, ora.S, ora.S, ora.S, ora.U32)
  	if err != nil {
  		return resp, err
  	}
  	defer stmt.Close()
  
  	rset, err := stmt.Qry()
  	if err != nil {
  		return resp, err
  	}
  	if rset.Next() {
  		resp.ObjectType = rset.Row[0].(string)
  		resp.ParentObjectType = rset.Row[1].(string)
  		resp.ParentFilterField = rset.Row[2].(string)
  		resp.SingleDetail = rset.Row[3].(uint32) != 0
  	}

  	if rset.Err() != nil {
  		return resp, rset.Err()

  	}
  
  	return resp, nil
  }