WIP: Implement WebDAV server

- Add a WebDAV server implementation using the `vweb` framework.
- The server supports basic authentication, request logging, and essential WebDAV methods.
- Implements file operations, authentication, and request logging.

Co-authored-by: mahmmoud.hassanein <mahmmoud.hassanein@gmail.com>

lib/vfs/webdav/prop.v

@@ -0,0 +1,181 @@
+module webdav
+
+import freeflowuniverse.herolib.core.pathlib
+import encoding.xml
+import os
+import time
+import vweb
+import net.urllib
+
+fn (mut app App) generate_response_element(path string, depth int) xml.XMLNode {
+	name := os.file_name(path)
+	href_link := urllib.path_escape(name)
+	href := xml.XMLNode{
+		name:     'D:href'
+		children: ['${href_link}']
+	}
+
+	propstat := app.generate_propstat_element(path, depth)
+
+	return xml.XMLNode{
+		name:     'D:response'
+		children: [href, propstat]
+	}
+}
+
+fn (mut app App) generate_propstat_element(path string, depth int) xml.XMLNode {
+	mut status := xml.XMLNode{
+		name:     'D:status'
+		children: ['HTTP/1.1 200 OK']
+	}
+
+	prop := app.generate_prop_element(path, depth) or {
+		// TODO: status should be according to returned error
+		return xml.XMLNode{
+			name:     'D:propstat'
+			children: [
+				xml.XMLNode{
+					name:     'D:status'
+					children: ['HTTP/1.1 500 Internal Server Error']
+				},
+			]
+		}
+	}
+
+	return xml.XMLNode{
+		name:     'D:propstat'
+		children: [prop, status]
+	}
+}
+
+fn (mut app App) generate_prop_element(path string, depth int) !xml.XMLNode {
+	if !os.exists(path) {
+		return error('not found')
+	}
+
+	stat := os.stat(path)!
+
+	// name := match os.is_dir(path) {
+	// 	true {
+	// 		os.base(path)
+	// 	}
+	// 	false {
+	// 		os.file_name(path)
+	// 	}
+	// }
+	// display_name := xml.XMLNode{
+	// 	name:     'D:displayname'
+	// 	children: ['${name}']
+	// }
+
+	content_length := if os.is_dir(path) { 0 } else { stat.size }
+	get_content_length := xml.XMLNode{
+		name:     'D:getcontentlength'
+		children: ['${content_length}']
+	}
+
+	ctime := format_iso8601(time.unix(stat.ctime))
+	creation_date := xml.XMLNode{
+		name:     'D:creationdate'
+		children: ['${ctime}']
+	}
+
+	mtime := format_iso8601(time.unix(stat.mtime))
+	get_last_mod := xml.XMLNode{
+		name:     'D:getlastmodified'
+		children: ['${mtime}']
+	}
+
+	content_type := match os.is_dir(path) {
+		true {
+			'httpd/unix-directory'
+		}
+		false {
+			app.get_file_content_type(path)
+		}
+	}
+
+	get_content_type := xml.XMLNode{
+		name:     'D:getcontenttype'
+		children: ['${content_type}']
+	}
+
+	mut get_resource_type_children := []xml.XMLNodeContents{}
+	if os.is_dir(path) {
+		get_resource_type_children << xml.XMLNode{
+			name: 'D:collection '
+		}
+	}
+
+	get_resource_type := xml.XMLNode{
+		name:     'D:resourcetype'
+		children: get_resource_type_children
+	}
+
+	mut nodes := []xml.XMLNodeContents{}
+	nodes << get_content_length
+	nodes << creation_date
+	nodes << get_last_mod
+	nodes << get_resource_type
+
+	if depth > 0 {
+		nodes << get_content_type
+	}
+
+	mut res := xml.XMLNode{
+		name:     'D:prop'
+		children: nodes.clone()
+	}
+
+	return res
+}
+
+fn (mut app App) get_file_content_type(path string) string {
+	ext := os.file_ext(path)
+	content_type := if v := vweb.mime_types[ext] {
+		v
+	} else {
+		'application/octet-stream'
+	}
+
+	return content_type
+}
+
+fn format_iso8601(t time.Time) string {
+	return '${t.year:04d}-${t.month:02d}-${t.day:02d}T${t.hour:02d}:${t.minute:02d}:${t.second:02d}Z'
+}
+
+fn (mut app App) get_responses(path string, depth int) ![]xml.XMLNodeContents {
+	mut responses := []xml.XMLNodeContents{}
+
+	if depth == 0 {
+		responses << app.generate_response_element(path, depth)
+		return responses
+	}
+
+	if os.is_dir(path) {
+		mut dir := pathlib.get_dir(path: path) or {
+			app.set_status(500, 'failed to get directory ${path}: ${err}')
+			return error('failed to get directory ${path}: ${err}')
+		}
+
+		entries := dir.list(recursive: false) or {
+			app.set_status(500, 'failed to list directory ${path}: ${err}')
+			return error('failed to list directory ${path}: ${err}')
+		}
+
+		// if entries.paths.len == 0 {
+		// 	// An empty directory
+		// 	responses << app.generate_response_element(path)
+		// 	return responses
+		// }
+
+		for entry in entries.paths {
+			responses << app.generate_response_element(entry.path, depth)
+		}
+	} else {
+		responses << app.generate_response_element(path, depth)
+	}
+
+	return responses
+}