Files
fnx_web/svelte/src/filesystem/Navigator.js

238 lines
6.7 KiB
JavaScript

import { fs_get_node } from "./FilesystemAPI";
import { fs_encode_path, fs_split_path } from "./FilesystemUtil";
export class Navigator {
// Parts of the raw API response
path = []
base_index = 0
children = []
permissions = {}
// base equals path[base_index]. It's updated every time the path updates
base = {}
// Initialized will be set to true when the first file or directory is loaded
initialized = false
shuffle = false
loading = false
// Whether navigation events should update the browser history
history_enabled = true
constructor(history_enabled = true) {
this.history_enabled = history_enabled
// If history logging is enabled we capture the popstate event, which
// fires when the user uses the back and forward buttons in the browser.
// Instead of reloading the page we use the navigator to navigate to the
// new page
if (history_enabled) {
window.onpopstate = () => {
// Get the part of the URL after the fs root and navigate to it
const path = document.location.pathname.replace("/d/", "")
this.navigate(decodeURIComponent(path), false)
}
}
}
// The Navigator acts as a svelte store. This allows for DOM reactivity.
// This works by implementing the store contract:
// https://svelte.dev/docs/svelte-components#script-4-prefix-stores-with-$-to-access-their-values
subscribers = []
subscribe(sub_func) {
// Immediately return the current value
sub_func(this)
this.subscribers.push(sub_func)
// Return the unsubscribe function
return () => {
this.subscribers.splice(this.subscribers.indexOf(sub_func), 1)
}
}
async navigate(path, push_history) {
if (path[0] !== "/") {
path = "/" + path
}
this.loading = true
console.debug("Navigating to path", path, push_history)
try {
const resp = await fs_get_node(path)
this.open_node(resp, push_history)
} catch (err) {
if (err.value && err.value === "path_not_found") {
if (path !== this.path[0].path && path !== "/" && path !== "") {
console.debug("Path", path, "was not found, trying to navigate to parent")
this.navigate(fs_split_path(path).parent, push_history)
}
} else if (err.message) {
console.error(err)
alert("Error: " + err.message)
} else {
console.error(err)
alert("Error: " + err)
}
} finally {
this.loading = false
}
}
async navigate_up() {
if (this.path.length > 1) {
await this.navigate(this.path[this.path.length - 2].path)
}
}
async reload() {
await this.navigate(this.base.path, false)
}
open_node(node, push_history) {
// Update window title and navigation history. If push_history is false
// we still replace the URL with replaceState. This way the user is not
// greeted to a 404 page when refreshing after renaming a file
if (this.history_enabled) {
window.document.title = node.path[node.base_index].name + " ~ pixeldrain"
const url = "/d" + fs_encode_path(node.path[node.base_index].path)
if (push_history) {
window.history.pushState({}, window.document.title, url)
} else {
window.history.replaceState({}, window.document.title, url)
}
}
// If the new node is a child of the previous node we save the parent's
// children array
if (node.path.length > 1 && node.path[node.path.length - 2].path === this.base.path) {
console.debug("Current parent path and new node path match. Saving siblings")
this.cached_siblings_path = node.path[node.path.length - 1].path
this.cached_siblings = this.children
}
// Sort directory children
sort_children(node.children)
// Update shared state
this.path = node.path
this.base_index = node.base_index
this.base = node.path[node.base_index]
this.children = node.children
this.permissions = node.permissions
this.initialized = true
console.debug("Opened node", node)
// Signal to our subscribers that the new node is loaded. This triggers
// the reactivity
for (let i = 0; i < this.subscribers.length; i++) {
this.subscribers[i](this)
}
// Remove spinner
this.loading = false
}
// These are used to navigate forward and backward within a directory (using
// the previous and next buttons on the toolbar). The cached siblings will
// be used so that we don't need to make an extra request to the parent
// directory. The siblings_path variable is used to verify that the parent
// directory is still the same. If it's different the siblings array is not
// used
cached_siblings_path = ""
cached_siblings = null
async get_siblings() {
// Check if we already have siblings cached
if (
this.cached_siblings === null ||
this.cached_siblings_path !== this.path[this.path.length - 2].path
) {
console.debug("Cached siblings not available. Fetching new")
const resp = await fs_get_node(this.path[this.path.length - 2].path)
// Sort directory children to make sure the order is consistent
sort_children(resp.children)
// Save new siblings in navigator state
this.cached_siblings_path = this.path[this.path.length - 2].path
this.cached_siblings = resp.children
}
return this.cached_siblings
}
// Opens a sibling of the currently open file. The offset is relative to the
// file which is currently open. Give a positive number to move forward and
// a negative number to move backward
async open_sibling(offset) {
if (this.path.length <= 1) {
return
}
this.loading = true
let siblings
try {
siblings = await this.get_siblings()
} catch (err) {
console.error(err)
alert(err)
this.loading = false
return
}
let next_sibling = null
if (this.shuffle) {
// Shuffle is on, pick a random sibling
for (let i = 0; i < 10; i++) {
next_sibling = siblings[Math.floor(Math.random() * siblings.length)]
// If we selected the same sibling we already have open we try
// again. Else we break the loop
if (next_sibling.name !== this.base.name) {
break
}
}
} else {
// Loop over the parent node's children to find the one which is
// currently open. Then, if possible, we save the one which comes before
// or after it
for (let i = 0; i < siblings.length; i++) {
if (
siblings[i].name === this.base.name &&
i + offset >= 0 && // Prevent underflow
i + offset < siblings.length // Prevent overflow
) {
next_sibling = siblings[i + offset]
break
}
}
}
// If we found a sibling we open it
if (next_sibling !== null) {
console.debug("Opening sibling", next_sibling.path)
this.navigate(next_sibling.path, true)
} else {
console.debug("No siblings found")
this.loading = false
}
}
}
const sort_children = (children) => {
children.sort((a, b) => {
// Sort directories before files
if (a.type !== b.type) {
return a.type === "dir" ? -1 : 1
}
return a.name.localeCompare(b.name, undefined, { numeric: true })
})
}