package samba

import (
	"bufio"
	"fmt"
	"os"
	"strings"
)

/*

	Samba Share Warpper

	Note that this module only provide exposing of local disk / storage.
	This module do not handle providing the virtualized interface for samba

*/

type ShareManager struct {
	SambaConfigPath string
}

type ShareConfig struct {
	Name       string
	Path       string
	ValidUsers []string
	ReadOnly   bool
	Browseable bool
	GuestOk    bool
}

func NewSambaShareManager() *ShareManager {
	return &ShareManager{
		SambaConfigPath: "/etc/samba/smb.conf",
	}
}

// ReadSambaShares reads the smb.conf file and extracts all existing shares
func (s *ShareManager) ReadSambaShares() ([]ShareConfig, error) {
	file, err := os.Open(s.SambaConfigPath)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	var shares []ShareConfig
	var currentShare *ShareConfig

	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		line := strings.TrimSpace(scanner.Text())

		// Check for section headers
		if strings.HasPrefix(line, "[") && strings.HasSuffix(line, "]") {
			if currentShare != nil {
				shares = append(shares, *currentShare)
			}
			currentShare = &ShareConfig{
				Name: strings.Trim(line, "[]"),
			}
			continue
		}

		// Check if we are currently processing a share section
		if currentShare != nil {
			tokens := strings.SplitN(line, "=", 2)
			if len(tokens) != 2 {
				continue
			}
			key := strings.TrimSpace(tokens[0])
			value := strings.TrimSpace(tokens[1])

			switch key {
			case "path":
				currentShare.Path = value
			case "valid users":
				currentShare.ValidUsers = strings.Fields(value)
			case "read only":
				currentShare.ReadOnly = (value == "yes")
			case "browseable":
				currentShare.Browseable = (value == "yes")
			case "guest ok":
				currentShare.GuestOk = (value == "yes")
			}
		}
	}

	// Add the last share if there is one
	if currentShare != nil {
		shares = append(shares, *currentShare)
	}

	// Check for scanner errors
	if err := scanner.Err(); err != nil {
		return nil, err
	}

	return shares, nil
}

// AppendSambaShareConfig appends the Samba share configuration to smb.conf
func (s *ShareManager) AppendSambaShareConfig(config string) error {
	file, err := os.OpenFile(s.SambaConfigPath, os.O_APPEND|os.O_WRONLY, 0644)
	if err != nil {
		return err
	}
	defer file.Close()

	if _, err := file.WriteString(config); err != nil {
		return err
	}

	return nil
}

// RemoveSambaShareConfig removes the Samba share configuration from smb.conf
func (s *ShareManager) RemoveSambaShareConfig(shareName string) error {
	// Open the smb.conf file for reading
	file, err := os.Open(s.SambaConfigPath)
	if err != nil {
		return err
	}
	defer file.Close()

	// Create a temporary file to store modified smb.conf
	tmpFile, err := os.CreateTemp("", "smb.conf.*.tmp")
	if err != nil {
		return err
	}
	defer tmpFile.Close()

	// Create a scanner to read the smb.conf file line by line
	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		line := scanner.Text()

		// Check if the line contains the share name
		if strings.HasPrefix(line, "["+shareName+"]") {
			// Skip the lines until the next section
			for scanner.Scan() {
				if strings.HasPrefix(scanner.Text(), "[") {
					break
				}
			}
			continue // Skip writing the share configuration to the temporary file
		}

		// Write the line to the temporary file
		_, err := fmt.Fprintln(tmpFile, line)
		if err != nil {
			return err
		}
	}

	// Check for scanner errors
	if err := scanner.Err(); err != nil {
		return err
	}

	// Close the original smb.conf file
	if err := file.Close(); err != nil {
		return err
	}

	// Close the temporary file
	if err := tmpFile.Close(); err != nil {
		return err
	}

	// Replace the original smb.conf file with the temporary file
	if err := os.Rename(tmpFile.Name(), "/etc/samba/smb.conf"); err != nil {
		return err
	}

	return nil
}