package pterm

import (
	"fmt"

	"github.com/gookit/color"

	"github.com/pterm/pterm/internal"
)

// RGB color model is an additive color model in which red, green, and blue light are added together in various ways to reproduce a broad array of colors.
// The name of the model comes from the initials of the three additive primary colors, red, green, and blue.
// https://en.wikipedia.org/wiki/RGB_color_model
type RGB struct {
	R          uint8
	G          uint8
	B          uint8
	Background bool
}

type RGBStyle struct {
	Options                []Color
	Foreground, Background RGB

	hasBg bool
}

// NewRGBStyle returns a new RGBStyle.
// The foreground color is required, the background color is optional.
// The colors will be set as is, ignoring the RGB.Background property.
func NewRGBStyle(foreground RGB, background ...RGB) RGBStyle {
	var s RGBStyle
	s.Foreground = foreground
	if len(background) > 0 {
		s.Background = background[0]
		s.hasBg = true
	}
	return s
}

// AddOptions adds options to the RGBStyle.
func (p RGBStyle) AddOptions(opts ...Color) RGBStyle {
	p.Options = append(p.Options, opts...)
	return p
}

// Print formats using the default formats for its operands and writes to standard output.
// Spaces are added between operands when neither is a string.
// It returns the number of bytes written and any write error encountered.
func (p RGBStyle) Print(a ...interface{}) *TextPrinter {
	Print(p.Sprint(a...))
	tp := TextPrinter(p)
	return &tp
}

// Println formats using the default formats for its operands and writes to standard output.
// Spaces are always added between operands and a newline is appended.
// It returns the number of bytes written and any write error encountered.
func (p RGBStyle) Println(a ...interface{}) *TextPrinter {
	Println(p.Sprint(a...))
	tp := TextPrinter(p)
	return &tp
}

// Printf formats according to a format specifier and writes to standard output.
// It returns the number of bytes written and any write error encountered.
func (p RGBStyle) Printf(format string, a ...interface{}) *TextPrinter {
	Printf(format, p.Sprint(a...))
	tp := TextPrinter(p)
	return &tp
}

// Printfln formats according to a format specifier and writes to standard output.
// Spaces are always added between operands and a newline is appended.
// It returns the number of bytes written and any write error encountered.
func (p RGBStyle) Printfln(format string, a ...interface{}) *TextPrinter {
	Printf(format, p.Sprint(a...))
	tp := TextPrinter(p)
	return &tp
}

// PrintOnError prints every error which is not nil.
// If every error is nil, nothing will be printed.
// This can be used for simple error checking.
func (p RGBStyle) PrintOnError(a ...interface{}) *TextPrinter {
	for _, arg := range a {
		if err, ok := arg.(error); ok {
			if err != nil {
				p.Println(err)
			}
		}
	}

	tp := TextPrinter(p)
	return &tp
}

// PrintOnErrorf wraps every error which is not nil and prints it.
// If every error is nil, nothing will be printed.
// This can be used for simple error checking.
func (p RGBStyle) PrintOnErrorf(format string, a ...interface{}) *TextPrinter {
	for _, arg := range a {
		if err, ok := arg.(error); ok {
			if err != nil {
				p.Println(fmt.Errorf(format, err))
			}
		}
	}

	tp := TextPrinter(p)
	return &tp
}

// Sprint formats using the default formats for its operands and returns the resulting string.
// Spaces are added between operands when neither is a string.
func (p RGBStyle) Sprint(a ...interface{}) string {
	var rgbStyle *color.RGBStyle
	if !p.hasBg {
		rgbStyle = color.NewRGBStyle(color.RGB(p.Foreground.R, p.Foreground.G, p.Foreground.B))
	} else {
		rgbStyle = color.NewRGBStyle(color.RGB(p.Foreground.R, p.Foreground.G, p.Foreground.B), color.RGB(p.Background.R, p.Background.G, p.Background.B))
	}
	if len(p.Options) > 0 {
		for _, opt := range p.Options {
			rgbStyle.AddOpts(color.Color(opt))
		}
	}
	return rgbStyle.Sprint(a...)
}

// Sprintln formats using the default formats for its operands and returns the resulting string.
// Spaces are always added between operands and a newline is appended.
func (p RGBStyle) Sprintln(a ...interface{}) string {
	return p.Sprint(a...) + "\n"
}

// Sprintf formats according to a format specifier and returns the resulting string.
func (p RGBStyle) Sprintf(format string, a ...interface{}) string {
	return p.Sprint(Sprintf(format, a...))
}

// Sprintfln formats according to a format specifier and returns the resulting string.
// Spaces are always added between operands and a newline is appended.
func (p RGBStyle) Sprintfln(format string, a ...interface{}) string {
	return p.Sprintf(format, a...) + "\n"
}

// GetValues returns the RGB values separately.
func (p RGB) GetValues() (r, g, b uint8) {
	return p.R, p.G, p.B
}

// NewRGB returns a new RGB.
func NewRGB(r, g, b uint8, background ...bool) RGB {
	var bg bool

	if len(background) > 0 {
		bg = background[0]
	}

	return RGB{R: r, G: g, B: b, Background: bg}
}

// Fade fades one RGB value (over other RGB values) to another RGB value, by giving the function a minimum, maximum and current value.
func (p RGB) Fade(min, max, current float32, end ...RGB) RGB {
	if max == current {
		return end[len(end)-1]
	}
	if min < 0 {
		max -= min
		current -= min
		min = 0
	}
	if len(end) == 1 {
		return RGB{
			R:          uint8(internal.MapRangeToRange(min, max, float32(p.R), float32(end[0].R), current)),
			G:          uint8(internal.MapRangeToRange(min, max, float32(p.G), float32(end[0].G), current)),
			B:          uint8(internal.MapRangeToRange(min, max, float32(p.B), float32(end[0].B), current)),
			Background: p.Background,
		}
	} else if len(end) > 1 {
		f := (max - min) / float32(len(end))
		tempCurrent := current
		if f > current {
			return p.Fade(min, f, current, end[0])
		} else {
			for i := 0; i < len(end)-1; i++ {
				tempCurrent -= f
				if f > tempCurrent {
					return end[i].Fade(min, min+f, tempCurrent, end[i+1])
				}
			}
		}
	}
	return p
}

// Sprint formats using the default formats for its operands and returns the resulting string.
// Spaces are added between operands when neither is a string.
func (p RGB) Sprint(a ...interface{}) string {
	if p.Background {
		return color.RGB(p.R, p.G, p.B, p.Background).Sprint(a...) + "\033[0m\033[K"
	}
	return color.RGB(p.R, p.G, p.B, p.Background).Sprint(a...)
}

// Sprintln formats using the default formats for its operands and returns the resulting string.
// Spaces are always added between operands and a newline is appended.
func (p RGB) Sprintln(a ...interface{}) string {
	return p.Sprint(Sprintln(a...))
}

// Sprintf formats according to a format specifier and returns the resulting string.
func (p RGB) Sprintf(format string, a ...interface{}) string {
	return p.Sprint(Sprintf(format, a...))
}

// Sprintfln formats according to a format specifier and returns the resulting string.
// Spaces are always added between operands and a newline is appended.
func (p RGB) Sprintfln(format string, a ...interface{}) string {
	return p.Sprintf(format, a...) + "\n"
}

// Print formats using the default formats for its operands and writes to standard output.
// Spaces are added between operands when neither is a string.
// It returns the number of bytes written and any write error encountered.
func (p RGB) Print(a ...interface{}) *TextPrinter {
	Print(p.Sprint(a...))
	tp := TextPrinter(p)
	return &tp
}

// Println formats using the default formats for its operands and writes to standard output.
// Spaces are always added between operands and a newline is appended.
// It returns the number of bytes written and any write error encountered.
func (p RGB) Println(a ...interface{}) *TextPrinter {
	Print(p.Sprintln(a...))
	tp := TextPrinter(p)
	return &tp
}

// Printf formats according to a format specifier and writes to standard output.
// It returns the number of bytes written and any write error encountered.
func (p RGB) Printf(format string, a ...interface{}) *TextPrinter {
	Print(p.Sprintf(format, a...))
	tp := TextPrinter(p)
	return &tp
}

// Printfln formats according to a format specifier and writes to standard output.
// Spaces are always added between operands and a newline is appended.
// It returns the number of bytes written and any write error encountered.
func (p RGB) Printfln(format string, a ...interface{}) *TextPrinter {
	Print(p.Sprintfln(format, a...))
	tp := TextPrinter(p)
	return &tp
}

// PrintOnError prints every error which is not nil.
// If every error is nil, nothing will be printed.
// This can be used for simple error checking.
func (p RGB) PrintOnError(a ...interface{}) *TextPrinter {
	for _, arg := range a {
		if err, ok := arg.(error); ok {
			if err != nil {
				p.Println(err)
			}
		}
	}

	tp := TextPrinter(p)
	return &tp
}

// PrintOnErrorf wraps every error which is not nil and prints it.
// If every error is nil, nothing will be printed.
// This can be used for simple error checking.
func (p RGB) PrintOnErrorf(format string, a ...interface{}) *TextPrinter {
	for _, arg := range a {
		if err, ok := arg.(error); ok {
			if err != nil {
				p.Println(fmt.Errorf(format, err))
			}
		}
	}

	tp := TextPrinter(p)
	return &tp
}

func (p RGB) ToRGBStyle() RGBStyle {
	if p.Background {
		return RGBStyle{Background: p}
	}

	return RGBStyle{Foreground: p}
}