package main
import (
"flag"
"fmt"
"math/rand"
"os"
"time"
)
var (
version string = "v0.6.1"
dump bool
random bool
notify bool
print bool
err error
body string
file string
reqInfo map[string]string
apodDate string
)
func main() {
// Early Check: If command was not passed then print usage and
// exit. Later command & service both are checked, this check
// is for version command. If not checked then running cetus
// without any args will fail because os.Args[1] will panic
// the program & produce runtime error.
if len(os.Args) == 1 {
printUsage()
os.Exit(0)
}
parseArgs()
}
// parseArgs will be parsing the arguments, it will verify if they are
// correct. Flag values are also set by parseArgs.
func parseArgs() {
// Running just `cetus` would've paniced the program if length
// of os.Args was not checked beforehand because there would
// be no os.Args[1].
switch os.Args[1] {
case "version", "-version", "--version", "-v":
fmt.Printf("Cetus %s\n", version)
os.Exit(0)
case "help", "-help", "--help", "-h":
// If help was passed then the program shouldn't exit
// with non-zero error code.
printUsage()
os.Exit(0)
case "set", "fetch":
// If command & service was not passed then print
// usage and exit.
if len(os.Args) < 3 {
printUsage()
os.Exit(1)
}
default:
fmt.Printf("Invalid command: %q\n", os.Args[1])
printUsage()
os.Exit(1)
}
rand.Seed(time.Now().Unix())
// If the program has reached this far then that means a valid
// command was passed & now we should check if a valid service
// was passed and parse the flags.
cetus := flag.NewFlagSet("cetus", flag.ExitOnError)
// We first declare common flags then service specific flags.
cetus.BoolVar(&dump, "dump", false, "Dump the response")
cetus.BoolVar(¬ify, "notify", false, "Send a desktop notification with info")
cetus.BoolVar(&print, "print", false, "Print information")
cetus.BoolVar(&random, "random", false, "Choose a random image")
switch os.Args[2] {
case "apod", "nasa":
defDate := time.Now().UTC().Format("2006-01-02")
cetus.StringVar(&apodDate, "date", defDate, "Date of NASA APOD to retrieve")
cetus.Parse(os.Args[3:])
execAPOD()
case "bpod", "bing":
cetus.Parse(os.Args[3:])
execBPOD()
default:
fmt.Printf("Invalid service: %q\n", os.Args[2])
printUsage()
os.Exit(1)
}
}