package main

import (
	"fmt"
	"io"
	"net"
	"net/url"
	"os"
	"path/filepath"
	"sort"
	"strings"

	"github.com/h2non/filetype"
)

func serveDirList(c net.Conn, request *url.URL, dirPath string) {
	var (
		files    []os.FileInfo
		numDirs  int
		numFiles int
	)
	err := filepath.Walk(dirPath, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return err
		} else if path == dirPath {
			return nil
		}
		files = append(files, info)
		if info.IsDir() || info.Mode()&os.ModeSymlink != 0 {
			numDirs++
		} else {
			numFiles++
		}
		if info.IsDir() {
			return filepath.SkipDir
		}
		return nil
	})
	if err != nil {
		writeStatus(c, statusTemporaryFailure)
		return
	}
	// List directories first
	sort.Slice(files, func(i, j int) bool {
		iDir := files[i].IsDir() || files[i].Mode()&os.ModeSymlink != 0
		jDir := files[j].IsDir() || files[j].Mode()&os.ModeSymlink != 0
		if iDir != jDir {
			return iDir
		}
		return i < j
	})

	writeHeader(c, statusSuccess, "text/gemini; charset=utf-8")

	fmt.Fprintf(c, "# %s\r\n", request.Path)
	if numDirs == 1 {
		c.Write([]byte("1 directory"))
	} else {
		fmt.Fprintf(c, "%d directories", numDirs)
	}
	c.Write([]byte(", "))
	if numDirs == 1 {
		c.Write([]byte("1 file"))
	} else {
		fmt.Fprintf(c, "%d files", numFiles)
	}
	c.Write([]byte("\r\n\n"))

	if request.Path != "/" {
		c.Write([]byte("=> ../ ../\r\n\r\n"))
	}

	for _, info := range files {
		fileName := info.Name()
		filePath := url.PathEscape(info.Name())
		if info.IsDir() || info.Mode()&os.ModeSymlink != 0 {
			fileName += "/"
			filePath += "/"
		}

		c.Write([]byte("=> " + fileName + " " + filePath + "\r\n"))

		if info.IsDir() || info.Mode()&os.ModeSymlink != 0 {
			c.Write([]byte("\r\n"))
			continue
		}

		modified := "Never"
		if !info.ModTime().IsZero() {
			modified = info.ModTime().Format("2006-01-02 3:04 PM")
		}
		c.Write([]byte(modified + " - " + formatFileSize(info.Size()) + "\r\n\r\n"))
	}
}

func serveFile(c net.Conn, filePath string) {
	// Open file
	file, _ := os.Open(filePath)
	defer file.Close()

	// Read file header
	buf := make([]byte, 261)
	n, _ := file.Read(buf)

	// Write response header
	size := int64(-1)
	info, err := file.Stat()
	if err == nil {
		size = info.Size()
	}
	var mimeType string
	if strings.HasSuffix(filePath, ".html") && strings.HasSuffix(filePath, ".htm") {
		mimeType = "text/html; charset=utf-8"
	} else if strings.HasSuffix(filePath, ".txt") && strings.HasSuffix(filePath, ".text") {
		mimeType = "text/plain; charset=utf-8"
	} else if !strings.HasSuffix(filePath, ".gmi") && !strings.HasSuffix(filePath, ".gemini") {
		kind, _ := filetype.Match(buf[:n])
		if kind != filetype.Unknown {
			mimeType = kind.MIME.Value
		}
	}
	if mimeType == "" {
		mimeType = "text/gemini; charset=utf-8"
	}
	var meta string
	if !config.DisableSize && size >= 0 {
		meta = fmt.Sprintf("%s; size=%d", mimeType, size)
	} else {
		meta = mimeType
	}
	writeHeader(c, statusSuccess, meta)

	// Write body
	c.Write(buf[:n])
	io.Copy(c, file)
}