package main

import (
	"flag"
	"fmt"
	"io/ioutil"
	"jsh"
)

func catFiles(queue chan *jsh.JshFrame) {
	// Get all of the non-flags. The rest were processed by the main function
	fileNames := flag.Args()
	for _, fileName := range fileNames {
		file, err := ioutil.ReadFile(fileName)

		var jshFrame jsh.JshFrame

		// If there's an error, output an error frame to the queue and continue
		if err != nil {
			errText := make(map[string]string)
			errText[fileName] = fmt.Sprintf("%s", err.Error())
			jshFrame = jsh.JshFrame{"", errText}
			queue <- &jshFrame
			continue
		}

		// Put the file contents into a frame and send them to the output
		output := jsh.CatOutput{}
		output.Files = []string{fileName}
		output.Output = string(file)
		jshFrame = jsh.JshFrame{output, ""}
		queue <- &jshFrame
	}
}

func runJsonMode() {
	queue := make(chan *jsh.JshFrame)
	done := make(chan bool)
	go jsh.OutputFrames(queue, done)
	catFiles(queue)
	close(queue)
	<-done
}

func main() {
	// TODO: Support more flags
	jsonModePtr := flag.Bool("json", false, "whether to use json mode for input and output")
	flag.Parse()

	if !*jsonModePtr {
		fmt.Printf("%s", jsh.FallbackWithArgs("/usr/bin/cat", flag.Args()))
	} else {
		runJsonMode()
	}
}