1 files changed, 220 insertions, 0 deletions
diff --git a/cmd/cetus/main.go b/cmd/cetus/main.go
new file mode 100644
index 0000000..7629cd2
--- /dev/null
+++ b/cmd/cetus/main.go
@@ -0,0 +1,220 @@
+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"
+	"framagit.org/andinus/cetus/pkg/cetus"
+)
+
+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)
+	}
+
+	if os.Args[1] == "version" {
+		cetus.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)
+	}
+}