package main

import (
	"bufio"
	"encoding/json"
	"fmt"
	"io"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
)

type Project struct {
	EnginePath  string `json:"enginePath"`
	ProjectPath string `json:"projectPath"`
	ProjectName string `json:"projectName"`
	Version     string `json:"engineVersion"`
}

func LoadProjects(projectFilePath string) ([]Project, error) {
	file, err := os.ReadFile(projectFilePath)
	if err != nil {
		return nil, err
	}
	var projects []Project
	if err := json.Unmarshal(file, &projects); err != nil {
		return nil, err
	}
	return projects, nil
}

func removeDir(path string) {
	err := os.RemoveAll(path)
	if err != nil {
		Log("Can't remove content at " + path)
	} else {
		Log("Removed " + path)
	}
}

func CleanUnrealProject(project Project) {
	dirs := []string{
		"Binaries",
		"DerivedDataCache",
		"Intermediate",
		"Saved",
		"Script",
	}

	for _, dir := range dirs {
		fullPath := filepath.Join(project.ProjectPath, dir)
		removeDir(fullPath)
	}

	pluginsPath := filepath.Join(project.ProjectPath, "Plugins")
	entries, err := os.ReadDir(pluginsPath)
	if err != nil {
		return
	}

	for _, entry := range entries {
		if !entry.IsDir() {
			continue
		}

		pluginDir := filepath.Join(pluginsPath, entry.Name())
		removeDir(filepath.Join(pluginDir, "Binaries"))
		removeDir(filepath.Join(pluginDir, "Intermediate"))
	}
}

func GenerateUnrealSolution(project Project) {
	var buildCmd string

	switch runtime.GOOS {
	case "linux":
		buildCmd = project.EnginePath + "/Engine/Build/BatchFiles/Linux/GenerateProjectFiles.sh"
	case "darwin":
		buildCmd = project.EnginePath + "/Engine/Build/BatchFiles/Mac/GenerateProjectFiles.sh"
	default:
		fmt.Println("Generate Project is not yet supported on Windows")
		return
	}

	projectCmd := project.ProjectPath + "/" + project.ProjectName + ".uproject"
	cmd := exec.Command(buildCmd, projectCmd, "-game")

	logToOutput(cmd)
}

func BuildUnrealSolution(project Project) {
	switch runtime.GOOS {
	case "linux":
		cmd := exec.Command("make", "-C", project.ProjectPath, project.ProjectName)
		logToOutput(cmd)
	default:
		fmt.Println("Build Project is not yet supported on Windows")
		return
	}
}

func RunUnrealProject(project Project) {
	var buildCmd string

	switch runtime.GOOS {
	case "linux":
		buildCmd = project.EnginePath + "/Engine/Binaries/Linux/UnrealEditor"
	case "darwin":
		buildCmd = project.EnginePath + "/Engine/Binaries/Mac/UnrealEditor.app/Contents/MacOS/UnrealEditor"
	default:
		buildCmd = project.EnginePath + "/Engine/Binaries/Win64/UnrealEditor.exe"
	}

	projectCmd := project.ProjectPath + "/" + project.ProjectName + ".uproject"
	cmd := exec.Command(buildCmd, projectCmd)

	logToOutput(cmd)
}

func logToOutput(cmd *exec.Cmd) {
	stdout, err := cmd.StdoutPipe()
	if err != nil {
		fmt.Println("Error during pipe stdout creation")
	}

	stderr, err := cmd.StderrPipe()
	if err != nil {
		fmt.Println("Error during pipe stderr creation")
	}

	if err := cmd.Start(); err != nil {
		fmt.Println("Error while loading command")
	}

	readPipe := func(reader io.ReadCloser) {
		scanner := bufio.NewScanner(reader)
		for scanner.Scan() {
			line := scanner.Text()
			Log(line)
		}
	}

	go readPipe(stdout)
	go readPipe(stderr)

	if err := cmd.Wait(); err != nil {
		fmt.Println("Error")
	}
}