package main

// import "fmt"
import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

func main() {
	arrays()
}

func arrays() {
	var arr [5]int // fills with default value
	arr[2] = 5
	fmt.Println(arr) // properly prints whole array

	arr2 := []int{1, 2, 3}
	arr3 := [5]int{1, 2, 3}
	fmt.Println(arr2, arr3, len(arr2))

	arr2d := [][]int{{1, 2}, {10, 20}}
	fmt.Println(arr2d)

	bigarr := []int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
	smallerArr := bigarr[:]
	fmt.Println(smallerArr)
	smallerArr1 := bigarr[4:]
	fmt.Println(smallerArr1)
	smallerArr2 := bigarr[:2]
	fmt.Println(smallerArr2)
	smallerArr3 := bigarr[4:6] // start index:end index
	fmt.Println(smallerArr3)

	var a []int = []int{1, 2, 3}
	b := append(a, 4, 5, 6)
	fmt.Println(b)

	for k, elem := range bigarr { // equivalent to: for k := 0; k < len(bigarr); k++
		fmt.Println(k, elem)
	}

	for _, elem := range bigarr { // equivalent to this C# code: foreach(var elem in bigarr)
		fmt.Println(elem)
	}
}

func loops() {
	i = 0
	for i < 5 {
		fmt.Println(i)
		i++
	}

	for {
		if i == 8 {
			break
		} else if i%2 == 0 {
			fmt.Println(i)
		}
		i++
	}

	for j := 0; j < 5; j++ {
		fmt.Println(j)
	}
}

func conditionals() {
	age := 21
	if driving_age := 18; age < driving_age {
		fmt.Println("You cannot drive!")
	} else if age < 16 {
		fmt.Println("You cannot use this app!")
	} else {
		fmt.Println("You're good")
	}

	n := 5
	switch n {
	case 1:
		fmt.Println("Very cool")
	case 4:
		fmt.Println("Not cool")
	default:
		fmt.Println("Bruh")
	}

	switch {
	case n > 3:
		fmt.Println("Yay")
	default:
		fmt.Println("Nay")
	}
}

func input() {
	scanner := bufio.NewScanner(os.Stdin)

	fmt.Printf("Type age: ")
	scanner.Scan()

	userInput := scanner.Text() // Always string, duuh
	// Variable, base (binary, octal, decimal, ..), integer size (8, 16, 32, 64, ..)
	// _ is an anonymous variable, so it doesn't get anywhere. Second returned variable is error
	// Bitsize 0 is normal int
	age, _ := strconv.ParseInt(userInput, 10, 0)

	fmt.Printf("You were born in %d!", 2021-age)

}

var i int

func variablesAndPrinting() {
	var msg string
	msg = "Hello World!"

	test := 5.98
	var num int = int(test)
	num += 4
	num++

	str := "Yoo"
	var str1 = "Bruh"

	//var v1, v2, v3 int = 45, 2342, 6634
	//v4, v5, v6 = 6653, true, "nafd"

	fmt.Println(msg, num) // Prints both with space in between
	fmt.Print(str, str1)
	fmt.Println()
	/* %T - type
	* %v - value
	* %% - escape % character
	* %t - prints bool
	* %b, %o, %d, %x - format int as base 2, 8, 10 and 16 repsectively
	* %e, %f, %g - format float as scientific notation, decimal no exponent (cuts of number) or large exponent (full number) respectively
	* %f - default width, default precision; %9f - width of 9, default precision; %.2f - default width, precision 2; %9.f - width of 9, precision 0; %9.2f - width of 9, precision 2;
	  - width forces certain string length (use negative number to add spaces to the right), it works with %s and %q also (%-9q)
	* %d - pads a number with a given digit, so %07d with force width of 7 and add 0s to the number
	* %s, %q - show string or show string with quotes
	*/
	fmt.Printf("%T", num) // Prints type
	out := fmt.Sprintf("%v %b", str, num)
	fmt.Println(out)
}