package main

import (
	"bufio"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"sort"
	"strings"
)

func main() {
	// Check for arguments
	if len(os.Args) < 2 {
		fmt.Println("Usage: runner <file-or-directory>")
		os.Exit(1)
	}

	// Select first argument, and check if it's a file or directory
	targetPath := os.Args[1]

	info, err := os.Stat(targetPath)
	if err != nil {
		fmt.Println("Error:", err)
		os.Exit(1)
	}

	var files []string
	if info.IsDir() {
		// Collect all .sh files from directory
		entries, err := os.ReadDir(targetPath)
		if err != nil {
			fmt.Println("Error reading directory:", err)
			os.Exit(1)
		}
		for _, e := range entries {
			if !e.IsDir() && strings.HasSuffix(e.Name(), ".sh") {
				files = append(files, filepath.Join(targetPath, e.Name()))
			}
		}
		sort.Strings(files)
	} else {
		files = append(files, targetPath)
	}

	originalDir, _ := os.Getwd()
	currentDir := originalDir

	for _, file := range files {
		// Change to the original directory before executing each file
		if err := os.Chdir(originalDir); err != nil {
			fmt.Println("Error changing to original directory:", err)
			os.Exit(1)
		}
		currentDir = originalDir

		fmt.Println("=== Executing file:", file, "===")
		if err := runCommandsFromFile(file, &currentDir); err != nil {
			fmt.Println("Error:", err)
			os.Exit(1)
		}
	}
}

func runCommandsFromFile(filename string, currentDir *string) error {
	// Try to open the file
	f, err := os.Open(filename)
	if err != nil {
		return fmt.Errorf("error opening file: %w", err)
	}
	defer f.Close()

	// Create a scanner to read the file line by line
	scanner := bufio.NewScanner(f)
	for scanner.Scan() {
		cmdLine := strings.TrimSpace(scanner.Text())

		if cmdLine == "" || strings.HasPrefix(cmdLine, "#") {
			continue
		}

		// Handle cd command
		if strings.HasPrefix(cmdLine, "cd ") {
			newDir := strings.TrimSpace(strings.TrimPrefix(cmdLine, "cd "))
			if strings.HasPrefix(newDir, "~") {
				home, _ := os.UserHomeDir()
				newDir = filepath.Join(home, strings.TrimPrefix(newDir, "~"))
			}
			if !filepath.IsAbs(newDir) {
				newDir = filepath.Join(*currentDir, newDir)
			}

			if err := os.Chdir(newDir); err != nil {
				return fmt.Errorf("failed to change directory: %w", err)
			}
			*currentDir, _ = os.Getwd()
			fmt.Println("Changed directory to:", *currentDir)
			continue
		}

		// Execute the command
		fmt.Println(">>> Executing:", cmdLine)
		cmd := exec.Command("bash", "-c", cmdLine)
		cmd.Stdout = os.Stdout
		cmd.Stderr = os.Stderr
		cmd.Dir = *currentDir

		if err := cmd.Run(); err != nil {
			fmt.Printf("Error detected! Stopping at: %s \n", cmdLine)
			return err
		}
	}

	if err := scanner.Err(); err != nil {
		return fmt.Errorf("error reading file: %w", err)
	}
	return nil
}