xmlDrawing.go

// Copyright 2016 - 2023 The excelize Authors. All rights reserved. Use of
// this source code is governed by a BSD-style license that can be found in
// the LICENSE file.
//
// Package excelize providing a set of functions that allow you to write to and
// read from XLAM / XLSM / XLSX / XLTM / XLTX files. Supports reading and
// writing spreadsheet documents generated by Microsoft Excel™ 2007 and later.
// Supports complex components by high compatibility, and provided streaming
// API for generating or reading data from a worksheet with huge amounts of
// data. This library needs Go version 1.16 or later.

package excelize

import (
	"encoding/xml"
	"sync"
)

// Source relationship and namespace list, associated prefixes and schema in which it was
// introduced.
var (
	NameSpaceDocumentPropertiesVariantTypes = xml.Attr{Name: xml.Name{Local: "vt", Space: "xmlns"}, Value: "http://schemas.openxmlformats.org/officeDocument/2006/docPropsVTypes"}
	NameSpaceDrawing2016SVG                 = xml.Attr{Name: xml.Name{Local: "asvg", Space: "xmlns"}, Value: "http://schemas.microsoft.com/office/drawing/2016/SVG/main"}
	NameSpaceDrawingML                      = xml.Attr{Name: xml.Name{Local: "a", Space: "xmlns"}, Value: "http://schemas.openxmlformats.org/drawingml/2006/main"}
	NameSpaceDrawingMLChart                 = xml.Attr{Name: xml.Name{Local: "c", Space: "xmlns"}, Value: "http://schemas.openxmlformats.org/drawingml/2006/chart"}
	NameSpaceDrawingMLSpreadSheet           = xml.Attr{Name: xml.Name{Local: "xdr", Space: "xmlns"}, Value: "http://schemas.openxmlformats.org/drawingml/2006/spreadsheetDrawing"}
	NameSpaceMacExcel2008Main               = xml.Attr{Name: xml.Name{Local: "mx", Space: "xmlns"}, Value: "http://schemas.microsoft.com/office/mac/excel/2008/main"}
	NameSpaceSpreadSheet                    = xml.Attr{Name: xml.Name{Local: "xmlns"}, Value: "http://schemas.openxmlformats.org/spreadsheetml/2006/main"}
	NameSpaceSpreadSheetExcel2006Main       = xml.Attr{Name: xml.Name{Local: "xne", Space: "xmlns"}, Value: "http://schemas.microsoft.com/office/excel/2006/main"}
	NameSpaceSpreadSheetX14                 = xml.Attr{Name: xml.Name{Local: "x14", Space: "xmlns"}, Value: "http://schemas.microsoft.com/office/spreadsheetml/2009/9/main"}
	NameSpaceSpreadSheetX15                 = xml.Attr{Name: xml.Name{Local: "x15", Space: "xmlns"}, Value: "http://schemas.microsoft.com/office/spreadsheetml/2010/11/main"}
	SourceRelationship                      = xml.Attr{Name: xml.Name{Local: "r", Space: "xmlns"}, Value: "http://schemas.openxmlformats.org/officeDocument/2006/relationships"}
	SourceRelationshipChart20070802         = xml.Attr{Name: xml.Name{Local: "c14", Space: "xmlns"}, Value: "http://schemas.microsoft.com/office/drawing/2007/8/2/chart"}
	SourceRelationshipChart2014             = xml.Attr{Name: xml.Name{Local: "c16", Space: "xmlns"}, Value: "http://schemas.microsoft.com/office/drawing/2014/chart"}
	SourceRelationshipChart201506           = xml.Attr{Name: xml.Name{Local: "c16r2", Space: "xmlns"}, Value: "http://schemas.microsoft.com/office/drawing/2015/06/chart"}
	SourceRelationshipCompatibility         = xml.Attr{Name: xml.Name{Local: "mc", Space: "xmlns"}, Value: "http://schemas.openxmlformats.org/markup-compatibility/2006"}
)

// Source relationship and namespace.
const (
	ContentTypeAddinMacro                         = "application/vnd.ms-excel.addin.macroEnabled.main+xml"
	ContentTypeDrawing                            = "application/vnd.openxmlformats-officedocument.drawing+xml"
	ContentTypeDrawingML                          = "application/vnd.openxmlformats-officedocument.drawingml.chart+xml"
	ContentTypeMacro                              = "application/vnd.ms-excel.sheet.macroEnabled.main+xml"
	ContentTypeSheetML                            = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml"
	ContentTypeSpreadSheetMLChartsheet            = "application/vnd.openxmlformats-officedocument.spreadsheetml.chartsheet+xml"
	ContentTypeSpreadSheetMLComments              = "application/vnd.openxmlformats-officedocument.spreadsheetml.comments+xml"
	ContentTypeSpreadSheetMLPivotCacheDefinition  = "application/vnd.openxmlformats-officedocument.spreadsheetml.pivotCacheDefinition+xml"
	ContentTypeSpreadSheetMLPivotTable            = "application/vnd.openxmlformats-officedocument.spreadsheetml.pivotTable+xml"
	ContentTypeSpreadSheetMLSharedStrings         = "application/vnd.openxmlformats-officedocument.spreadsheetml.sharedStrings+xml"
	ContentTypeSpreadSheetMLTable                 = "application/vnd.openxmlformats-officedocument.spreadsheetml.table+xml"
	ContentTypeSpreadSheetMLWorksheet             = "application/vnd.openxmlformats-officedocument.spreadsheetml.worksheet+xml"
	ContentTypeTemplate                           = "application/vnd.openxmlformats-officedocument.spreadsheetml.template.main+xml"
	ContentTypeTemplateMacro                      = "application/vnd.ms-excel.template.macroEnabled.main+xml"
	ContentTypeVBA                                = "application/vnd.ms-office.vbaProject"
	ContentTypeVML                                = "application/vnd.openxmlformats-officedocument.vmlDrawing"
	NameSpaceDrawingMLMain                        = "http://schemas.openxmlformats.org/drawingml/2006/main"
	NameSpaceDublinCore                           = "http://purl.org/dc/elements/1.1/"
	NameSpaceDublinCoreMetadataInitiative         = "http://purl.org/dc/dcmitype/"
	NameSpaceDublinCoreTerms                      = "http://purl.org/dc/terms/"
	NameSpaceExtendedProperties                   = "http://schemas.openxmlformats.org/officeDocument/2006/extended-properties"
	NameSpaceXML                                  = "http://www.w3.org/XML/1998/namespace"
	NameSpaceXMLSchemaInstance                    = "http://www.w3.org/2001/XMLSchema-instance"
	SourceRelationshipChart                       = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/chart"
	SourceRelationshipChartsheet                  = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/chartsheet"
	SourceRelationshipComments                    = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/comments"
	SourceRelationshipDialogsheet                 = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/dialogsheet"
	SourceRelationshipDrawingML                   = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/drawing"
	SourceRelationshipDrawingVML                  = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/vmlDrawing"
	SourceRelationshipExtendProperties            = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/extended-properties"
	SourceRelationshipHyperLink                   = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink"
	SourceRelationshipImage                       = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/image"
	SourceRelationshipOfficeDocument              = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument"
	SourceRelationshipPivotCache                  = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotCacheDefinition"
	SourceRelationshipPivotTable                  = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotTable"
	SourceRelationshipSharedStrings               = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/sharedStrings"
	SourceRelationshipTable                       = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/table"
	SourceRelationshipVBAProject                  = "http://schemas.microsoft.com/office/2006/relationships/vbaProject"
	SourceRelationshipWorkSheet                   = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/worksheet"
	StrictNameSpaceDocumentPropertiesVariantTypes = "http://purl.oclc.org/ooxml/officeDocument/docPropsVTypes"
	StrictNameSpaceDrawingMLMain                  = "http://purl.oclc.org/ooxml/drawingml/main"
	StrictNameSpaceExtendedProperties             = "http://purl.oclc.org/ooxml/officeDocument/extendedProperties"
	StrictNameSpaceSpreadSheet                    = "http://purl.oclc.org/ooxml/spreadsheetml/main"
	StrictSourceRelationship                      = "http://purl.oclc.org/ooxml/officeDocument/relationships"
	StrictSourceRelationshipChart                 = "http://purl.oclc.org/ooxml/officeDocument/relationships/chart"
	StrictSourceRelationshipComments              = "http://purl.oclc.org/ooxml/officeDocument/relationships/comments"
	StrictSourceRelationshipExtendProperties      = "http://purl.oclc.org/ooxml/officeDocument/relationships/extendedProperties"
	StrictSourceRelationshipImage                 = "http://purl.oclc.org/ooxml/officeDocument/relationships/image"
	StrictSourceRelationshipOfficeDocument        = "http://purl.oclc.org/ooxml/officeDocument/relationships/officeDocument"
	// ExtURIConditionalFormattings is the extLst child element
	// ([ISO/IEC29500-1:2016] section 18.2.10) of the worksheet element
	// ([ISO/IEC29500-1:2016] section 18.3.1.99) is extended by the addition of
	// new child ext elements ([ISO/IEC29500-1:2016] section 18.2.7)
	ExtURIConditionalFormattings = "{78C0D931-6437-407D-A8EE-F0AAD7539E65}"
	ExtURIDataValidations        = "{CCE6A557-97BC-4B89-ADB6-D9C93CAAB3DF}"
	ExtURIDrawingBlip            = "{28A0092B-C50C-407E-A947-70E740481C1C}"
	ExtURIIgnoredErrors          = "{01252117-D84E-4E92-8308-4BE1C098FCBB}"
	ExtURIMacExcelMX             = "{64002731-A6B0-56B0-2670-7721B7C09600}"
	ExtURIProtectedRanges        = "{FC87AEE6-9EDD-4A0A-B7FB-166176984837}"
	ExtURISlicerCachesListX14    = "{BBE1A952-AA13-448e-AADC-164F8A28A991}"
	ExtURISlicerListX14          = "{A8765BA9-456A-4DAB-B4F3-ACF838C121DE}"
	ExtURISlicerListX15          = "{3A4CF648-6AED-40f4-86FF-DC5316D8AED3}"
	ExtURISparklineGroups        = "{05C60535-1F16-4fd2-B633-F4F36F0B64E0}"
	ExtURISVG                    = "{96DAC541-7B7A-43D3-8B79-37D633B846F1}"
	ExtURITimelineRefs           = "{7E03D99C-DC04-49d9-9315-930204A7B6E9}"
	ExtURIWebExtensions          = "{F7C9EE02-42E1-4005-9D12-6889AFFD525C}"
)

// Excel specifications and limits
const (
	MaxCellStyles        = 64000
	MaxColumns           = 16384
	MaxColumnWidth       = 255
	MaxFieldLength       = 255
	MaxFilePathLength    = 207
	MaxFontFamilyLength  = 31
	MaxFontSize          = 409
	MaxRowHeight         = 409
	MaxSheetNameLength   = 31
	MinColumns           = 1
	MinFontSize          = 1
	StreamChunkSize      = 1 << 24
	TotalCellChars       = 32767
	TotalRows            = 1048576
	TotalSheetHyperlinks = 65529
	UnzipSizeLimit       = 1000 << 24
	// pivotTableVersion should be greater than 3. One or more of the
	// PivotTables chosen are created in a version of Excel earlier than
	// Excel 2007 or in compatibility mode. Slicer can only be used with
	// PivotTables created in Excel 2007 or a newer version of Excel.
	pivotTableVersion           = 3
	defaultPictureScale         = 1.0
	defaultChartDimensionWidth  = 480
	defaultChartDimensionHeight = 290
	defaultChartLegendPosition  = "bottom"
	defaultChartShowBlanksAs    = "gap"
	defaultShapeSize            = 160
	defaultShapeLineWidth       = 1
)

// ColorMappingType is the type of color transformation.
type ColorMappingType byte

// Color transformation types enumeration.
const (
	ColorMappingTypeLight1 ColorMappingType = iota
	ColorMappingTypeDark1
	ColorMappingTypeLight2
	ColorMappingTypeDark2
	ColorMappingTypeAccent1
	ColorMappingTypeAccent2
	ColorMappingTypeAccent3
	ColorMappingTypeAccent4
	ColorMappingTypeAccent5
	ColorMappingTypeAccent6
	ColorMappingTypeHyperlink
	ColorMappingTypeFollowedHyperlink
	ColorMappingTypeUnset int = -1
)

// IndexedColorMapping is the table of default mappings from indexed color value
// to RGB value. Note that 0-7 are redundant of 8-15 to preserve backwards
// compatibility. A legacy indexing scheme for colors that is still required
// for some records, and for backwards compatibility with legacy formats. This
// element contains a sequence of RGB color values that correspond to color
// indexes (zero-based). When using the default indexed color palette, the
// values are not written out, but instead are implied. When the color palette
// has been modified from default, then the entire color palette is written
// out.
var IndexedColorMapping = []string{
	"000000", "FFFFFF", "FF0000", "00FF00", "0000FF", "FFFF00", "FF00FF", "00FFFF",
	"000000", "FFFFFF", "FF0000", "00FF00", "0000FF", "FFFF00", "FF00FF", "00FFFF",
	"800000", "008000", "000080", "808000", "800080", "008080", "C0C0C0", "808080",
	"9999FF", "993366", "FFFFCC", "CCFFFF", "660066", "FF8080", "0066CC", "CCCCFF",
	"000080", "FF00FF", "FFFF00", "00FFFF", "800080", "800000", "008080", "0000FF",
	"00CCFF", "CCFFFF", "CCFFCC", "FFFF99", "99CCFF", "FF99CC", "CC99FF", "FFCC99",
	"3366FF", "33CCCC", "99CC00", "FFCC00", "FF9900", "FF6600", "666699", "969696",
	"003366", "339966", "003300", "333300", "993300", "993366", "333399", "333333",
	"000000", "FFFFFF",
}

// supportedImageTypes defined supported image types.
var supportedImageTypes = map[string]string{
	".emf": ".emf", ".emz": ".emz", ".gif": ".gif", ".jpeg": ".jpeg",
	".jpg": ".jpeg", ".png": ".png", ".svg": ".svg", ".tif": ".tiff",
	".tiff": ".tiff", ".wmf": ".wmf", ".wmz": ".wmz",
}

// supportedContentTypes defined supported file format types.
var supportedContentTypes = map[string]string{
	".xlam": ContentTypeAddinMacro,
	".xlsm": ContentTypeMacro,
	".xlsx": ContentTypeSheetML,
	".xltm": ContentTypeTemplateMacro,
	".xltx": ContentTypeTemplate,
}

// supportedUnderlineTypes defined supported underline types.
var supportedUnderlineTypes = []string{"none", "single", "double"}

// supportedDrawingUnderlineTypes defined supported underline types in drawing
// markup language.
var supportedDrawingUnderlineTypes = []string{
	"none", "words", "sng", "dbl", "heavy", "dotted", "dottedHeavy", "dash", "dashHeavy", "dashLong", "dashLongHeavy", "dotDash", "dotDashHeavy", "dotDotDash", "dotDotDashHeavy", "wavy", "wavyHeavy",
	"wavyDbl",
}

// xlsxCNvPr directly maps the cNvPr (Non-Visual Drawing Properties). This
// element specifies non-visual canvas properties. This allows for additional
// information that does not affect the appearance of the picture to be stored.
type xlsxCNvPr struct {
	ID         int             `xml:"id,attr"`
	Name       string          `xml:"name,attr"`
	Descr      string          `xml:"descr,attr"`
	Title      string          `xml:"title,attr,omitempty"`
	HlinkClick *xlsxHlinkClick `xml:"a:hlinkClick"`
}

// xlsxHlinkClick (Click Hyperlink) Specifies the on-click hyperlink
// information to be applied to a run of text. When the hyperlink text is
// clicked the link is fetched.
type xlsxHlinkClick struct {
	R              string `xml:"xmlns:r,attr,omitempty"`
	RID            string `xml:"r:id,attr,omitempty"`
	InvalidURL     string `xml:"invalidUrl,attr,omitempty"`
	Action         string `xml:"action,attr,omitempty"`
	TgtFrame       string `xml:"tgtFrame,attr,omitempty"`
	Tooltip        string `xml:"tooltip,attr,omitempty"`
	History        bool   `xml:"history,attr,omitempty"`
	HighlightClick bool   `xml:"highlightClick,attr,omitempty"`
	EndSnd         bool   `xml:"endSnd,attr,omitempty"`
}

// xlsxPicLocks directly maps the picLocks (Picture Locks). This element
// specifies all locking properties for a graphic frame. These properties inform
// the generating application about specific properties that have been
// previously locked and thus should not be changed.
type xlsxPicLocks struct {
	NoAdjustHandles    bool `xml:"noAdjustHandles,attr,omitempty"`
	NoChangeArrowheads bool `xml:"noChangeArrowheads,attr,omitempty"`
	NoChangeAspect     bool `xml:"noChangeAspect,attr"`
	NoChangeShapeType  bool `xml:"noChangeShapeType,attr,omitempty"`
	NoCrop             bool `xml:"noCrop,attr,omitempty"`
	NoEditPoints       bool `xml:"noEditPoints,attr,omitempty"`
	NoGrp              bool `xml:"noGrp,attr,omitempty"`
	NoMove             bool `xml:"noMove,attr,omitempty"`
	NoResize           bool `xml:"noResize,attr,omitempty"`
	NoRot              bool `xml:"noRot,attr,omitempty"`
	NoSelect           bool `xml:"noSelect,attr,omitempty"`
}

// xlsxBlip element specifies the existence of an image (binary large image or
// picture) and contains a reference to the image data.
type xlsxBlip struct {
	Embed   string                        `xml:"r:embed,attr"`
	Cstate  string                        `xml:"cstate,attr,omitempty"`
	R       string                        `xml:"xmlns:r,attr"`
	ExtList *xlsxEGOfficeArtExtensionList `xml:"a:extLst"`
}

// xlsxStretch directly maps the stretch element. This element specifies that a
// BLIP should be stretched to fill the target rectangle. The other option is a
// tile where a BLIP is tiled to fill the available area.
type xlsxStretch struct {
	FillRect string `xml:"a:fillRect"`
}

// xlsxOff directly maps the colOff and rowOff element. This element is used to
// specify the column offset within a cell.
type xlsxOff struct {
	X int `xml:"x,attr"`
	Y int `xml:"y,attr"`
}

// xlsxExt directly maps the ext element.
type xlsxExt struct {
	Cx int `xml:"cx,attr"`
	Cy int `xml:"cy,attr"`
}

// xlsxPrstGeom directly maps the prstGeom (Preset geometry). This element
// specifies when a preset geometric shape should be used instead of a custom
// geometric shape. The generating application should be able to render all
// preset geometries enumerated in the ST_ShapeType list.
type xlsxPrstGeom struct {
	Prst string `xml:"prst,attr"`
}

// xlsxXfrm directly maps the xfrm (2D Transform for Graphic Frame). This
// element specifies the transform to be applied to the corresponding graphic
// frame. This transformation is applied to the graphic frame just as it would
// be for a shape or group shape.
type xlsxXfrm struct {
	Off xlsxOff `xml:"a:off"`
	Ext xlsxExt `xml:"a:ext"`
}

// xlsxCNvPicPr directly maps the cNvPicPr (Non-Visual Picture Drawing
// Properties). This element specifies the non-visual properties for the picture
// canvas. These properties are to be used by the generating application to
// determine how certain properties are to be changed for the picture object in
// question.
type xlsxCNvPicPr struct {
	PicLocks xlsxPicLocks `xml:"a:picLocks"`
}

// directly maps the nvPicPr (Non-Visual Properties for a Picture). This element
// specifies all non-visual properties for a picture. This element is a
// container for the non-visual identification properties, shape properties and
// application properties that are to be associated with a picture. This allows
// for additional information that does not affect the appearance of the picture
// to be stored.
type xlsxNvPicPr struct {
	CNvPr    xlsxCNvPr    `xml:"xdr:cNvPr"`
	CNvPicPr xlsxCNvPicPr `xml:"xdr:cNvPicPr"`
}

// xlsxCTSVGBlip specifies a graphic element in Scalable Vector Graphics (SVG)
// format.
type xlsxCTSVGBlip struct {
	XMLNSaAVG string `xml:"xmlns:asvg,attr"`
	Embed     string `xml:"r:embed,attr"`
	Link      string `xml:"r:link,attr,omitempty"`
}

// xlsxCTOfficeArtExtension used for future extensibility and is seen elsewhere
// throughout the drawing area.
type xlsxCTOfficeArtExtension struct {
	XMLName xml.Name      `xml:"a:ext"`
	URI     string        `xml:"uri,attr"`
	SVGBlip xlsxCTSVGBlip `xml:"asvg:svgBlip"`
}

// xlsxEGOfficeArtExtensionList used for future extensibility and is seen
// elsewhere throughout the drawing area.
type xlsxEGOfficeArtExtensionList struct {
	Ext []xlsxCTOfficeArtExtension `xml:"ext"`
}

// xlsxBlipFill directly maps the blipFill (Picture Fill). This element
// specifies the kind of picture fill that the picture object has. Because a
// picture has a picture fill already by default, it is possible to have two
// fills specified for a picture object.
type xlsxBlipFill struct {
	Blip    xlsxBlip    `xml:"a:blip"`
	Stretch xlsxStretch `xml:"a:stretch"`
}

// xlsxLineProperties specifies the width of a line in EMUs. This simple type
// has a minimum value of greater than or equal to 0. This simple type has a
// maximum value of less than or equal to 20116800.
type xlsxLineProperties struct {
	W int `xml:"w,attr,omitempty"`
}

// xlsxSpPr directly maps the spPr (Shape Properties). This element specifies
// the visual shape properties that can be applied to a picture. These are the
// same properties that are allowed to describe the visual properties of a shape
// but are used here to describe the visual appearance of a picture within a
// document.
type xlsxSpPr struct {
	Xfrm     xlsxXfrm           `xml:"a:xfrm"`
	PrstGeom xlsxPrstGeom       `xml:"a:prstGeom"`
	Ln       xlsxLineProperties `xml:"a:ln"`
}

// xlsxPic elements encompass the definition of pictures within the DrawingML
// framework. While pictures are in many ways very similar to shapes they have
// specific properties that are unique in order to optimize for picture-
// specific scenarios.
type xlsxPic struct {
	NvPicPr  xlsxNvPicPr  `xml:"xdr:nvPicPr"`
	BlipFill xlsxBlipFill `xml:"xdr:blipFill"`
	SpPr     xlsxSpPr     `xml:"xdr:spPr"`
}

// xlsxFrom specifies the starting anchor.
type xlsxFrom struct {
	Col    int `xml:"xdr:col"`
	ColOff int `xml:"xdr:colOff"`
	Row    int `xml:"xdr:row"`
	RowOff int `xml:"xdr:rowOff"`
}

// xlsxTo directly specifies the ending anchor.
type xlsxTo struct {
	Col    int `xml:"xdr:col"`
	ColOff int `xml:"xdr:colOff"`
	Row    int `xml:"xdr:row"`
	RowOff int `xml:"xdr:rowOff"`
}

// xdrClientData directly maps the clientData element. An empty element which
// specifies (via attributes) certain properties related to printing and
// selection of the drawing object. The fLocksWithSheet attribute (either true
// or false) determines whether to disable selection when the sheet is
// protected, and fPrintsWithSheet attribute (either true or false) determines
// whether the object is printed when the sheet is printed.
type xdrClientData struct {
	FLocksWithSheet  bool `xml:"fLocksWithSheet,attr"`
	FPrintsWithSheet bool `xml:"fPrintsWithSheet,attr"`
}

// xdrCellAnchor directly maps the oneCellAnchor (One Cell Anchor Shape Size)
// and twoCellAnchor (Two Cell Anchor Shape Size). This element specifies a two
// cell anchor placeholder for a group, a shape, or a drawing element. It moves
// with cells and its extents are in EMU units.
type xdrCellAnchor struct {
	EditAs       string         `xml:"editAs,attr,omitempty"`
	Pos          *xlsxPoint2D   `xml:"xdr:pos"`
	From         *xlsxFrom      `xml:"xdr:from"`
	To           *xlsxTo        `xml:"xdr:to"`
	Ext          *xlsxExt       `xml:"xdr:ext"`
	Sp           *xdrSp         `xml:"xdr:sp"`
	Pic          *xlsxPic       `xml:"xdr:pic,omitempty"`
	GraphicFrame string         `xml:",innerxml"`
	ClientData   *xdrClientData `xml:"xdr:clientData"`
}

// xlsxPoint2D describes the position of a drawing element within a spreadsheet.
type xlsxPoint2D struct {
	XMLName xml.Name `xml:"xdr:pos"`
	X       int      `xml:"x,attr"`
	Y       int      `xml:"y,attr"`
}

// xlsxWsDr directly maps the root element for a part of this content type shall
// wsDr.
type xlsxWsDr struct {
	sync.Mutex
	XMLName          xml.Name                `xml:"xdr:wsDr"`
	A                string                  `xml:"xmlns:a,attr,omitempty"`
	Xdr              string                  `xml:"xmlns:xdr,attr,omitempty"`
	R                string                  `xml:"xmlns:r,attr,omitempty"`
	AlternateContent []*xlsxAlternateContent `xml:"mc:AlternateContent"`
	AbsoluteAnchor   []*xdrCellAnchor        `xml:"xdr:absoluteAnchor"`
	OneCellAnchor    []*xdrCellAnchor        `xml:"xdr:oneCellAnchor"`
	TwoCellAnchor    []*xdrCellAnchor        `xml:"xdr:twoCellAnchor"`
}

// xlsxGraphicFrame (Graphic Frame) directly maps the xdr:graphicFrame element.
// This element specifies the existence of a graphics frame. This frame contains
// a graphic that was generated by an external source and needs a container in
// which to be displayed on the slide surface.
type xlsxGraphicFrame struct {
	XMLName          xml.Name             `xml:"xdr:graphicFrame"`
	Macro            string               `xml:"macro,attr"`
	NvGraphicFramePr xlsxNvGraphicFramePr `xml:"xdr:nvGraphicFramePr"`
	Xfrm             xlsxXfrm             `xml:"xdr:xfrm"`
	Graphic          *xlsxGraphic         `xml:"a:graphic"`
}

// xlsxNvGraphicFramePr (Non-Visual Properties for a Graphic Frame) directly
// maps the xdr:nvGraphicFramePr element. This element specifies all non-visual
// properties for a graphic frame. This element is a container for the non-
// visual identification properties, shape properties and application properties
// that are to be associated with a graphic frame. This allows for additional
// information that does not affect the appearance of the graphic frame to be
// stored.
type xlsxNvGraphicFramePr struct {
	CNvPr                *xlsxCNvPr `xml:"xdr:cNvPr"`
	ChicNvGraphicFramePr string     `xml:"xdr:cNvGraphicFramePr"`
}

// xlsxGraphic (Graphic Object) directly maps the a:graphic element. This
// element specifies the existence of a single graphic object. Document authors
// should refer to this element when they wish to persist a graphical object of
// some kind. The specification for this graphical object is provided entirely
// by the document author and referenced within the graphicData child element.
type xlsxGraphic struct {
	GraphicData *xlsxGraphicData `xml:"a:graphicData"`
}

// xlsxGraphicData (Graphic Object Data) directly maps the a:graphicData
// element. This element specifies the reference to a graphic object within the
// document. This graphic object is provided entirely by the document authors
// who choose to persist this data within the document.
type xlsxGraphicData struct {
	URI   string     `xml:"uri,attr"`
	Chart *xlsxChart `xml:"c:chart,omitempty"`
}

// xlsxChart (Chart) directly maps the c:chart element.
type xlsxChart struct {
	C   string `xml:"xmlns:c,attr"`
	RID string `xml:"r:id,attr"`
	R   string `xml:"xmlns:r,attr"`
}

// xdrSp (Shape) directly maps the xdr:sp element. This element specifies the
// existence of a single shape. A shape can either be a preset or a custom
// geometry, defined using the SpreadsheetDrawingML framework. In addition to a
// geometry each shape can have both visual and non-visual properties attached.
// Text and corresponding styling information can also be attached to a shape.
// This shape is specified along with all other shapes within either the shape
// tree or group shape elements.
type xdrSp struct {
	Macro    string     `xml:"macro,attr"`
	Textlink string     `xml:"textlink,attr"`
	NvSpPr   *xdrNvSpPr `xml:"xdr:nvSpPr"`
	SpPr     *xlsxSpPr  `xml:"xdr:spPr"`
	Style    *xdrStyle  `xml:"xdr:style"`
	TxBody   *xdrTxBody `xml:"xdr:txBody"`
}

// xdrNvSpPr (Non-Visual Properties for a Shape) directly maps the xdr:nvSpPr
// element. This element specifies all non-visual properties for a shape. This
// element is a container for the non-visual identification properties, shape
// properties and application properties that are to be associated with a shape.
// This allows for additional information that does not affect the appearance of
// the shape to be stored.
type xdrNvSpPr struct {
	CNvPr   *xlsxCNvPr  `xml:"xdr:cNvPr"`
	CNvSpPr *xdrCNvSpPr `xml:"xdr:cNvSpPr"`
}

// xdrCNvSpPr (Connection Non-Visual Shape Properties) directly maps the
// xdr:cNvSpPr element. This element specifies the set of non-visual properties
// for a connection shape. These properties specify all data about the
// connection shape which do not affect its display within a spreadsheet.
type xdrCNvSpPr struct {
	TxBox bool `xml:"txBox,attr"`
}

// xdrStyle (Shape Style) directly maps the xdr:style element. The element
// specifies the style that is applied to a shape and the corresponding
// references for each of the style components such as lines and fills.
type xdrStyle struct {
	LnRef     *aRef     `xml:"a:lnRef"`
	FillRef   *aRef     `xml:"a:fillRef"`
	EffectRef *aRef     `xml:"a:effectRef"`
	FontRef   *aFontRef `xml:"a:fontRef"`
}

// aRef directly maps the a:lnRef, a:fillRef and a:effectRef element.
type aRef struct {
	Idx       int            `xml:"idx,attr"`
	ScrgbClr  *aScrgbClr     `xml:"a:scrgbClr"`
	SchemeClr *attrValString `xml:"a:schemeClr"`
	SrgbClr   *attrValString `xml:"a:srgbClr"`
}

// aScrgbClr (RGB Color Model - Percentage Variant) directly maps the a:scrgbClr
// element. This element specifies a color using the red, green, blue RGB color
// model. Each component, red, green, and blue is expressed as a percentage from
// 0% to 100%. A linear gamma of 1.0 is assumed.
type aScrgbClr struct {
	R float64 `xml:"r,attr"`
	G float64 `xml:"g,attr"`
	B float64 `xml:"b,attr"`
}

// aFontRef (Font Reference) directly maps the a:fontRef element. This element
// represents a reference to a themed font. When used it specifies which themed
// font to use along with a choice of color.
type aFontRef struct {
	Idx       string         `xml:"idx,attr"`
	SchemeClr *attrValString `xml:"a:schemeClr"`
}

// xdrTxBody (Shape Text Body) directly maps the xdr:txBody element. This
// element specifies the existence of text to be contained within the
// corresponding shape. All visible text and visible text related properties are
// contained within this element. There can be multiple paragraphs and within
// paragraphs multiple runs of text.
type xdrTxBody struct {
	BodyPr *aBodyPr `xml:"a:bodyPr"`
	P      []*aP    `xml:"a:p"`
}

// GraphicOptions directly maps the format settings of the picture.
type GraphicOptions struct {
	PrintObject     *bool
	Locked          *bool
	LockAspectRatio bool
	AutoFit         bool
	OffsetX         int
	OffsetY         int
	ScaleX          float64
	ScaleY          float64
	Hyperlink       string
	HyperlinkType   string
	Positioning     string
}

// Shape directly maps the format settings of the shape.
type Shape struct {
	Macro     string
	Type      string
	Width     uint
	Height    uint
	Format    GraphicOptions
	Color     ShapeColor
	Line      ShapeLine
	Paragraph []ShapeParagraph
}

// ShapeParagraph directly maps the format settings of the paragraph in
// the shape.
type ShapeParagraph struct {
	Font Font
	Text string
}

// ShapeColor directly maps the color settings of the shape.
type ShapeColor struct {
	Line   string
	Fill   string
	Effect string
}

// ShapeLine directly maps the line settings of the shape.
type ShapeLine struct {
	Width *float64
}