package main
import (
"flag"
"fmt"
"math/rand"
"os"
"time"
"framagit.org/andinus/cetus/pkg/apod"
"framagit.org/andinus/cetus/pkg/background"
"framagit.org/andinus/cetus/pkg/bpod"
)
func main() {
// Early Check: If command was not passed then print usage and
// exit. Later command & service both are checked, this check
// if 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(1)
}
version := "v0.5.0"
if os.Args[1] == "version" {
fmt.Printf("Cetus %s\n", version)
os.Exit(0)
}
// If command & service was not passed then print usage and
// exit.
if len(os.Args) < 3 {
printUsage()
os.Exit(1)
}
rand.Seed(time.Now().Unix())
apodCmd := flag.NewFlagSet("apod", flag.ExitOnError)
defDate := time.Now().UTC().Format("2006-01-02")
// Flags to parse for apod service.
apodAPI := apodCmd.String("api", "https://api.nasa.gov/planetary/apod", "APOD API link")
apodKey := apodCmd.String("api-key", "DEMO_KEY", "NASA API Key for expanded usage")
apodDate := apodCmd.String("date", defDate, "Date of NASA APOD to retrieve")
apodRand := apodCmd.Bool("random", false, "Choose a date random starting from 1995-06-16")
apodPathOnly := apodCmd.Bool("path-only", false, "Print only the path")
apodQuiet := apodCmd.Bool("quiet", false, "Stay quiet")
apodDump := apodCmd.Bool("dump", false, "Dump received response")
bpodCmd := flag.NewFlagSet("bpod", flag.ExitOnError)
// Flags to parse for bpod service.
bpodAPI := bpodCmd.String("api", "https://www.bing.com/HPImageArchive.aspx", "BPOD API")
bpodRand := bpodCmd.Bool("random", false, "Choose a random image from last week's BPOD")
bpodPathOnly := bpodCmd.Bool("path-only", false, "Print only the path")
bpodQuiet := bpodCmd.Bool("quiet", false, "Stay quiet")
bpodDump := bpodCmd.Bool("dump", false, "Dump received response")
// Switching on commands will cause more repetition than
// switching on service. If we switch on commands then switch
// on service will have to be replicated on every command
// switch. Reverse is also true, this way we will repeat
// command switch in every service but we do so in a better
// way.
//
// However we check if the correct command was passed. version
// command is not included because it has been dealt with
// earlier in the program & the program should've exited after
// that, if it reaches here then it's an error.
switch os.Args[1] {
case "set", "fetch":
default:
fmt.Printf("Invalid command: %q\n", os.Args[1])
printUsage()
os.Exit(1)
}
switch os.Args[2] {
case "apod", "nasa":
apodCmd.Parse(os.Args[3:])
case "bpod", "bing":
bpodCmd.Parse(os.Args[3:])
default:
fmt.Printf("Invalid service: %q\n", os.Args[2])
printUsage()
os.Exit(1)
}
if apodCmd.Parsed() {
// reqInfo holds all the parameters that needs to be
// sent with the request. GetJson() will pack apiKey &
// date in params map before sending it to another
// function. Adding params here will not change the
// behaviour of the function, changes have to be made
// in GetJson() too.
reqInfo := make(map[string]string)
reqInfo["api"] = string(*apodAPI)
reqInfo["apiKey"] = string(*apodKey)
reqInfo["date"] = string(*apodDate)
if *apodRand {
reqInfo["apiKey"] = apod.RandDate()
}
body, err := apod.GetJson(reqInfo)
chkErr(err)
if *apodDump {
fmt.Printf(body)
os.Exit(0)
}
res := apod.Res{}
err = apod.UnmarshalJson(&res, body)
chkErr(err)
// res.Msg will be returned when there is error on
// user input or the api server.
if len(res.Msg) != 0 {
fmt.Printf("Message: %s", res.Msg)
os.Exit(1)
}
// If path-only is passed then it will only print the
// path, even if quiet is passed. If the user wants
// the program to be quiet then path-only shouldn't be
// passed. If path-only is not passed & quiet is also
// not passed then print the response.
//
// Path is only printed when the media type is an
// image because res.HDURL is empty on non image media
// type.
if *apodPathOnly {
fmt.Println(res.HDURL)
} else if !*apodQuiet {
apod.Print(res)
}
// Proceed only if the command was set because if it
// was fetch then it's already finished & should exit
// now.
if os.Args[1] == "fetch" {
os.Exit(0)
}
// Try to set background only if the media type is an
// image.
if res.MediaType == "image" {
err = background.Set(res.HDURL)
chkErr(err)
}
}
if bpodCmd.Parsed() {
// reqInfo here works similar to apodCmd block's
// reqInfo, refer to explanation there.
reqInfo := make(map[string]string)
reqInfo["api"] = string(*bpodAPI)
if *bpodRand {
reqInfo["random"] = "true"
}
body, err := bpod.GetJson(reqInfo)
chkErr(err)
if *bpodDump {
fmt.Printf(body)
os.Exit(0)
}
res, err := bpod.UnmarshalJson(body)
chkErr(err)
// Correct format
res.Url = fmt.Sprintf("%s%s", "https://www.bing.com", res.Url)
dt, err := time.Parse("20060102", res.StartDate)
chkErr(err)
res.StartDate = dt.Format("2006-01-02")
// path-only here works similar to apodCmd block's
// path-only, refer to explanation there.
if *bpodPathOnly {
fmt.Println(res.Url)
} else if !*bpodQuiet {
bpod.Print(res)
}
// Proceed only if the command was set because if it
// was fetch then it's already finished & should exit
// now.
if os.Args[1] == "fetch" {
os.Exit(0)
}
err = background.Set(res.Url)
chkErr(err)
}
}
func printUsage() {
fmt.Println("Usage: cetus <command> <service> [<args>]\n")
fmt.Println("Commands: ")
fmt.Println(" set Set the latest image as background")
fmt.Println(" fetch Fetch the latest image information")
fmt.Println(" version Print version")
fmt.Println("Services: ")
fmt.Println(" apod NASA Astronomy Picture of the Day")
fmt.Println(" bpod Bing Photo of the Day")
}
func chkErr(err error) {
if err != nil {
fmt.Println(err)
os.Exit(1)
}
}