package main

import (
	"encoding/json"
	"fmt"
	"log"
	"os/exec"
	"strings"
)

type tree struct {
	Id            int    `json:"id"`
	Name          string `json:"name,omitempty"`
	AppId         string `json:"app_id,omitempty"`
	Type          string `json:"type,omitempty"`
	Nodes         []tree `json:"nodes,omitempty"`
	FloatingNodes []tree `json:"floating_nodes,omitempty"`
}

type window struct {
	Id           int
	AppIdAndName string
}

func flatten(in tree, windows *[]window) {
	if in.Name != "" && (in.Type == "con" || in.Type == "floating_con") {
		*windows = append(*windows, window{in.Id, in.AppId + " " + in.Name})
	}
	for _, node := range append(in.Nodes, in.FloatingNodes...) {
		flatten(node, windows)
	}
}

func getWindowNames(windows []window) string {
	var windowNames []string
	for _, idAndName := range windows {
		windowNames = append(windowNames, idAndName.AppIdAndName)
	}
	return strings.Join(windowNames, "\n")
}

func selectWithWofi(windows string) string {
	cmd := exec.Command("wofi", "-i", "-d")
	cmd.Stdin = strings.NewReader(windows)
	stdout, err := cmd.Output()
	if err != nil {
		return ""
	}
	return strings.TrimSpace(string(stdout))
}

func findWindowId(windowName string, windows []window) int {
	for _, window := range windows {
		if windowName == window.AppIdAndName {
			return window.Id
		}
	}
	log.Fatal("Invalid Window Name")
	return -1
}

func switchToWindow(id int) {
	arg1 := fmt.Sprintf("[con_id=%d]", id)
	cmd := exec.Command("swaymsg", arg1, "focus")
	cmd.Start()
}

func main() {

	cmd := exec.Command("swaymsg", "-r", "-t", "get_tree")
	stdout, err := cmd.Output()
	if err != nil {
		log.Fatal(err)
		return
	}

	var swaymsg_output tree
	if err := json.Unmarshal(stdout, &swaymsg_output); err != nil {
		log.Fatal(err)
	}

	var windows []window
	flatten(swaymsg_output, &windows)

	if selected := selectWithWofi(getWindowNames(windows)); selected != "" {
		windowId := findWindowId(selected, windows)
		switchToWindow(windowId)
	}
}