package main

import (
    "fmt"
    "time"
)

func main() {
    // 1. Basic Switch
    // Implicit break: Go only runs the selected case.
    i := 2
    fmt.Print("Write ", i, " as ")
    switch i {
    case 1:
        fmt.Println("one")
    case 2:
        fmt.Println("two")
    case 3:
        fmt.Println("three")
    }

    // 2. Multiple Expressions in Case
    // You can separate values with commas.
    day := time.Now().Weekday()
    switch day {
    case time.Saturday, time.Sunday:
        fmt.Println("It's the weekend")
    default:
        fmt.Println("It's a weekday")
    }

    // 3. Switch without Expression (Tagless)
    // Acts like a long if-else chain. Clean way to write complex logic.
    t := time.Now()
    switch {
    case t.Hour() < 12:
        fmt.Println("Good morning!")
    case t.Hour() < 17:
        fmt.Println("Good afternoon!")
    default:
        fmt.Println("Good evening!")
    }

    // 4. Type Switch
    // Discover the dynamic type of an interface value.
    whatAmI := func(i interface{}) {
        switch t := i.(type) {
        case bool:
            fmt.Println("I'm a bool")
        case int:
            fmt.Println("I'm an int")
        default:
            fmt.Printf("Don't know type %T\n", t)
        }
    }
    whatAmI(true)
    whatAmI(1)
    whatAmI("hello")
}