// Copyright 2016 - 2020 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 XLSX / XLSM / XLTM files. Supports reading and writing
// spreadsheet documents generated by Microsoft Exce™ 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 1.10 or later.

package excelize

import "fmt"

// SheetViewOption is an option of a view of a worksheet. See
// SetSheetViewOptions().
type SheetViewOption interface {
	setSheetViewOption(view *xlsxSheetView)
}

// SheetViewOptionPtr is a writable SheetViewOption. See
// GetSheetViewOptions().
type SheetViewOptionPtr interface {
	SheetViewOption
	getSheetViewOption(view *xlsxSheetView)
}

type (
	// DefaultGridColor is a SheetViewOption. It specifies a flag indicating that
	// the consuming application should use the default grid lines color (system
	// dependent). Overrides any color specified in colorId.
	DefaultGridColor bool
	// RightToLeft is a SheetViewOption. It specifies a flag indicating whether
	// the sheet is in 'right to left' display mode. When in this mode, Column A
	// is on the far right, Column B ;is one column left of Column A, and so on.
	// Also, information in cells is displayed in the Right to Left format.
	RightToLeft bool
	// ShowFormulas is a SheetViewOption. It specifies a flag indicating whether
	// this sheet should display formulas.
	ShowFormulas bool
	// ShowGridLines is a SheetViewOption. It specifies a flag indicating whether
	// this sheet should display gridlines.
	ShowGridLines bool
	// ShowRowColHeaders is a SheetViewOption. It specifies a flag indicating
	// whether the sheet should display row and column headings.
	ShowRowColHeaders bool
	// ZoomScale is a SheetViewOption. It specifies a window zoom magnification
	// for current view representing percent values. This attribute is restricted
	// to values ranging from 10 to 400. Horizontal & Vertical scale together.
	ZoomScale float64
	// TopLeftCell is a SheetViewOption. It specifies a location of the top left
	// visible cell Location of the top left visible cell in the bottom right
	// pane (when in Left-to-Right mode).
	TopLeftCell string
	// ShowZeros is a SheetViewOption. It specifies a flag indicating
	// whether to "show a zero in cells that have zero value".
	// When using a formula to reference another cell which is empty, the referenced value becomes 0
	// when the flag is true. (Default setting is true.)
	ShowZeros bool

	/* TODO
	// ShowWhiteSpace is a SheetViewOption. It specifies a flag indicating
	// whether page layout view shall display margins. False means do not display
	// left, right, top (header), and bottom (footer) margins (even when there is
	// data in the header or footer).
	ShowWhiteSpace bool
	// WindowProtection is a SheetViewOption.
	WindowProtection bool
	*/
)

// Defaults for each option are described in XML schema for CT_SheetView

func (o TopLeftCell) setSheetViewOption(view *xlsxSheetView) {
	view.TopLeftCell = string(o)
}

func (o *TopLeftCell) getSheetViewOption(view *xlsxSheetView) {
	*o = TopLeftCell(string(view.TopLeftCell))
}

func (o DefaultGridColor) setSheetViewOption(view *xlsxSheetView) {
	view.DefaultGridColor = boolPtr(bool(o))
}

func (o *DefaultGridColor) getSheetViewOption(view *xlsxSheetView) {
	*o = DefaultGridColor(defaultTrue(view.DefaultGridColor)) // Excel default: true
}

func (o RightToLeft) setSheetViewOption(view *xlsxSheetView) {
	view.RightToLeft = bool(o) // Excel default: false
}

func (o *RightToLeft) getSheetViewOption(view *xlsxSheetView) {
	*o = RightToLeft(view.RightToLeft)
}

func (o ShowFormulas) setSheetViewOption(view *xlsxSheetView) {
	view.ShowFormulas = bool(o) // Excel default: false
}

func (o *ShowFormulas) getSheetViewOption(view *xlsxSheetView) {
	*o = ShowFormulas(view.ShowFormulas) // Excel default: false
}

func (o ShowGridLines) setSheetViewOption(view *xlsxSheetView) {
	view.ShowGridLines = boolPtr(bool(o))
}

func (o *ShowGridLines) getSheetViewOption(view *xlsxSheetView) {
	*o = ShowGridLines(defaultTrue(view.ShowGridLines)) // Excel default: true
}

func (o ShowZeros) setSheetViewOption(view *xlsxSheetView) {
	view.ShowZeros = boolPtr(bool(o))
}

func (o *ShowZeros) getSheetViewOption(view *xlsxSheetView) {
	*o = ShowZeros(defaultTrue(view.ShowZeros)) // Excel default: true
}

func (o ShowRowColHeaders) setSheetViewOption(view *xlsxSheetView) {
	view.ShowRowColHeaders = boolPtr(bool(o))
}

func (o *ShowRowColHeaders) getSheetViewOption(view *xlsxSheetView) {
	*o = ShowRowColHeaders(defaultTrue(view.ShowRowColHeaders)) // Excel default: true
}

func (o ZoomScale) setSheetViewOption(view *xlsxSheetView) {
	// This attribute is restricted to values ranging from 10 to 400.
	if float64(o) >= 10 && float64(o) <= 400 {
		view.ZoomScale = float64(o)
	}
}

func (o *ZoomScale) getSheetViewOption(view *xlsxSheetView) {
	*o = ZoomScale(view.ZoomScale)
}

// getSheetView returns the SheetView object
func (f *File) getSheetView(sheetName string, viewIndex int) (*xlsxSheetView, error) {
	xlsx, err := f.workSheetReader(sheetName)
	if err != nil {
		return nil, err
	}
	if viewIndex < 0 {
		if viewIndex < -len(xlsx.SheetViews.SheetView) {
			return nil, fmt.Errorf("view index %d out of range", viewIndex)
		}
		viewIndex = len(xlsx.SheetViews.SheetView) + viewIndex
	} else if viewIndex >= len(xlsx.SheetViews.SheetView) {
		return nil, fmt.Errorf("view index %d out of range", viewIndex)
	}

	return &(xlsx.SheetViews.SheetView[viewIndex]), err
}

// SetSheetViewOptions sets sheet view options. The viewIndex may be negative
// and if so is counted backward (-1 is the last view).
//
// Available options:
//
//    DefaultGridColor(bool)
//    RightToLeft(bool)
//    ShowFormulas(bool)
//    ShowGridLines(bool)
//    ShowRowColHeaders(bool)
//    ZoomScale(float64)
//    TopLeftCell(string)
//
// Example:
//
//    err = f.SetSheetViewOptions("Sheet1", -1, ShowGridLines(false))
//
func (f *File) SetSheetViewOptions(name string, viewIndex int, opts ...SheetViewOption) error {
	view, err := f.getSheetView(name, viewIndex)
	if err != nil {
		return err
	}

	for _, opt := range opts {
		opt.setSheetViewOption(view)
	}
	return nil
}

// GetSheetViewOptions gets the value of sheet view options. The viewIndex may
// be negative and if so is counted backward (-1 is the last view).
//
// Available options:
//
//    DefaultGridColor(bool)
//    RightToLeft(bool)
//    ShowFormulas(bool)
//    ShowGridLines(bool)
//    ShowRowColHeaders(bool)
//    ZoomScale(float64)
//    TopLeftCell(string)
//
// Example:
//
//    var showGridLines excelize.ShowGridLines
//    err = f.GetSheetViewOptions("Sheet1", -1, &showGridLines)
//
func (f *File) GetSheetViewOptions(name string, viewIndex int, opts ...SheetViewOptionPtr) error {
	view, err := f.getSheetView(name, viewIndex)
	if err != nil {
		return err
	}

	for _, opt := range opts {
		opt.getSheetViewOption(view)
	}
	return nil
}