import { defineMessages, type KeyBinding, type MessageDescriptor } from '@modrinth/ui'
import type { RouteLocationNormalizedLoaded } from 'vue-router'

import { getLastBrowseContentProjectType, isBrowseContentProjectType } from '@/helpers/settings'

/** Which half of the settings page an action belongs to. */
export type ShortcutGroupId = 'scroll' | 'nav'

/** Theme store fields that switch an action on. */
export type ShortcutEnabledField =
	| 'quickScrollEnabled'
	| 'shortcutNavHome'
	| 'shortcutNavWorlds'
	| 'shortcutNavDiscover'
	| 'shortcutNavSkins'
	| 'shortcutNavMultiplayer'
	| 'shortcutNavLibrary'
	| 'shortcutNavLab'
	| 'shortcutNavDownloads'
	| 'shortcutNavCreate'
	| 'shortcutNavSettings'

export interface ShortcutContext {
	worldsTabEnabled: boolean
	offline: boolean
}

export interface ShortcutAction {
	/** Stable id, used for the binding, the enable flag and the settings row. */
	id: string
	group: ShortcutGroupId
	enabledField: ShortcutEnabledField
	defaultBinding: KeyBinding
	label: MessageDescriptor
	description: MessageDescriptor
	/** Navigation actions know where they lead. */
	target?: (route: RouteLocationNormalizedLoaded) => string
	/** Navigation actions that are not reachable right now. */
	unavailable?: (context: ShortcutContext) => boolean
	/** Scrolling actions move the page's own scroller. */
	applyScroll?: (scroller: HTMLElement) => void
}

/**
 * Declared here rather than assembled from the action ids, so the extractor can
 * see them; an id built at runtime is one a translation pass would drop.
 */
const messages = defineMessages({
	scrollTop: {
		id: 'app.shortcut-settings.home-action',
		defaultMessage: 'Scroll to the top',
	},
	scrollTopDescription: {
		id: 'app.shortcut-settings.home-action-description',
		defaultMessage: 'Moves the page you are reading to the top.',
	},
	scrollBottom: {
		id: 'app.shortcut-settings.end-action',
		defaultMessage: 'Scroll to the bottom',
	},
	scrollBottomDescription: {
		id: 'app.shortcut-settings.end-action-description',
		defaultMessage: 'Moves the page you are reading to the bottom.',
	},
	scrollUp: {
		id: 'app.shortcut-settings.page-up-action',
		defaultMessage: 'Scroll up one screen',
	},
	scrollUpDescription: {
		id: 'app.shortcut-settings.page-up-action-description',
		defaultMessage: 'Moves the page you are reading up by one screen.',
	},
	scrollDown: {
		id: 'app.shortcut-settings.page-down-action',
		defaultMessage: 'Scroll down one screen',
	},
	scrollDownDescription: {
		id: 'app.shortcut-settings.page-down-action-description',
		defaultMessage: 'Moves the page you are reading down by one screen.',
	},
	navHome: { id: 'app.shortcut-settings.nav-home', defaultMessage: 'Home' },
	navHomeDescription: {
		id: 'app.shortcut-settings.nav-home-description',
		defaultMessage: 'Jump to the Home page.',
	},
	navWorlds: { id: 'app.shortcut-settings.nav-worlds', defaultMessage: 'Worlds' },
	navWorldsDescription: {
		id: 'app.shortcut-settings.nav-worlds-description',
		defaultMessage: 'Jump to your worlds.',
	},
	navDiscover: {
		id: 'app.shortcut-settings.nav-discover',
		defaultMessage: 'Discover content',
	},
	navDiscoverDescription: {
		id: 'app.shortcut-settings.nav-discover-description',
		defaultMessage: 'Jump to browsing content.',
	},
	navSkins: { id: 'app.shortcut-settings.nav-skins', defaultMessage: 'Skin selector' },
	navSkinsDescription: {
		id: 'app.shortcut-settings.nav-skins-description',
		defaultMessage: 'Jump to the skin selector.',
	},
	navMultiplayer: { id: 'app.shortcut-settings.nav-multiplayer', defaultMessage: 'Multiplayer' },
	navMultiplayerDescription: {
		id: 'app.shortcut-settings.nav-multiplayer-description',
		defaultMessage: 'Jump to multiplayer.',
	},
	navLibrary: { id: 'app.shortcut-settings.nav-library', defaultMessage: 'Library' },
	navLibraryDescription: {
		id: 'app.shortcut-settings.nav-library-description',
		defaultMessage: 'Jump to your library.',
	},
	navLab: { id: 'app.shortcut-settings.nav-lab', defaultMessage: 'Lab' },
	navLabDescription: {
		id: 'app.shortcut-settings.nav-lab-description',
		defaultMessage: 'Jump to the Lab.',
	},
	navDownloads: { id: 'app.shortcut-settings.nav-downloads', defaultMessage: 'Downloads' },
	navDownloadsDescription: {
		id: 'app.shortcut-settings.nav-downloads-description',
		defaultMessage: 'Jump to downloads.',
	},
	navCreate: { id: 'app.shortcut-settings.nav-create', defaultMessage: 'Create new instance' },
	navCreateDescription: {
		id: 'app.shortcut-settings.nav-create-description',
		defaultMessage: 'Jump to creating a new instance.',
	},
	navSettings: { id: 'app.shortcut-settings.nav-settings', defaultMessage: 'Settings' },
	navSettingsDescription: {
		id: 'app.shortcut-settings.nav-settings-description',
		defaultMessage: 'Jump to the settings.',
	},
})

function keyboard(code: string, mod = false, alt = false, shift = false): KeyBinding {
	return { device: 'keyboard', code, mod, alt, shift }
}

/**
 * Resolves the Discover content target from the current route, so the nav
 * button and the keyboard shortcut share one source of truth.
 */
export function discoverContentTarget(route: RouteLocationNormalizedLoaded): string {
	const projectType = route.params.projectType
	if (
		!route.query.i &&
		!route.query.sid &&
		!route.query.wid &&
		typeof projectType === 'string' &&
		isBrowseContentProjectType(projectType)
	) {
		return `/browse/${projectType}`
	}

	return `/browse/${getLastBrowseContentProjectType()}`
}

/**
 * Every shortcut the launcher answers to. The binding here is the one a fresh
 * install uses; a recorded binding is stored separately and wins over it.
 */
export const SHORTCUT_ACTIONS: ShortcutAction[] = [
	{
		id: 'shortcutScrollTop',
		group: 'scroll',
		enabledField: 'quickScrollEnabled',
		defaultBinding: keyboard('Home'),
		label: messages.scrollTop,
		description: messages.scrollTopDescription,
		applyScroll: (scroller) => scroller.scrollTo({ top: 0, behavior: 'smooth' }),
	},
	{
		id: 'shortcutScrollBottom',
		group: 'scroll',
		enabledField: 'quickScrollEnabled',
		defaultBinding: keyboard('End'),
		label: messages.scrollBottom,
		description: messages.scrollBottomDescription,
		applyScroll: (scroller) =>
			scroller.scrollTo({ top: scroller.scrollHeight, behavior: 'smooth' }),
	},
	{
		id: 'shortcutScrollUp',
		group: 'scroll',
		enabledField: 'quickScrollEnabled',
		defaultBinding: keyboard('PageUp'),
		label: messages.scrollUp,
		description: messages.scrollUpDescription,
		applyScroll: (scroller) => {
			// Immediate scrolling keeps rapid key repeats responsive.
			scroller.scrollTop = Math.max(0, scroller.scrollTop - scroller.clientHeight * 0.9)
		},
	},
	{
		id: 'shortcutScrollDown',
		group: 'scroll',
		enabledField: 'quickScrollEnabled',
		defaultBinding: keyboard('PageDown'),
		label: messages.scrollDown,
		description: messages.scrollDownDescription,
		applyScroll: (scroller) => {
			scroller.scrollTop = Math.min(
				scroller.scrollHeight,
				scroller.scrollTop + scroller.clientHeight * 0.9,
			)
		},
	},
	{
		id: 'shortcutNavHome',
		group: 'nav',
		enabledField: 'shortcutNavHome',
		defaultBinding: keyboard('Digit1', true),
		label: messages.navHome,
		description: messages.navHomeDescription,
		target: () => '/',
	},
	{
		id: 'shortcutNavWorlds',
		group: 'nav',
		enabledField: 'shortcutNavWorlds',
		defaultBinding: keyboard('Digit2', true),
		label: messages.navWorlds,
		description: messages.navWorldsDescription,
		target: () => '/worlds',
		unavailable: (context) => !context.worldsTabEnabled,
	},
	{
		id: 'shortcutNavDiscover',
		group: 'nav',
		enabledField: 'shortcutNavDiscover',
		defaultBinding: keyboard('Digit3', true),
		label: messages.navDiscover,
		description: messages.navDiscoverDescription,
		target: (route) => discoverContentTarget(route),
		unavailable: (context) => context.offline,
	},
	{
		id: 'shortcutNavSkins',
		group: 'nav',
		enabledField: 'shortcutNavSkins',
		defaultBinding: keyboard('Digit4', true),
		label: messages.navSkins,
		description: messages.navSkinsDescription,
		target: () => '/skins',
	},
	{
		id: 'shortcutNavMultiplayer',
		group: 'nav',
		enabledField: 'shortcutNavMultiplayer',
		defaultBinding: keyboard('Digit5', true),
		label: messages.navMultiplayer,
		description: messages.navMultiplayerDescription,
		target: () => '/multiplayer',
	},
	{
		id: 'shortcutNavLibrary',
		group: 'nav',
		enabledField: 'shortcutNavLibrary',
		defaultBinding: keyboard('Digit6', true),
		label: messages.navLibrary,
		description: messages.navLibraryDescription,
		target: () => '/library',
	},
	{
		id: 'shortcutNavLab',
		group: 'nav',
		enabledField: 'shortcutNavLab',
		defaultBinding: keyboard('Digit7', true),
		label: messages.navLab,
		description: messages.navLabDescription,
		target: () => '/lab',
	},
	{
		id: 'shortcutNavDownloads',
		group: 'nav',
		enabledField: 'shortcutNavDownloads',
		defaultBinding: keyboard('Digit8', true),
		label: messages.navDownloads,
		description: messages.navDownloadsDescription,
		target: () => '/downloads',
	},
	{
		id: 'shortcutNavCreate',
		group: 'nav',
		enabledField: 'shortcutNavCreate',
		defaultBinding: keyboard('Digit9', true),
		label: messages.navCreate,
		description: messages.navCreateDescription,
		target: () => '/create',
		unavailable: (context) => context.offline,
	},
	{
		id: 'shortcutNavSettings',
		group: 'nav',
		enabledField: 'shortcutNavSettings',
		defaultBinding: keyboard('Comma', true),
		label: messages.navSettings,
		description: messages.navSettingsDescription,
		target: () => '/settings',
	},
]

export const SCROLL_ACTIONS = SHORTCUT_ACTIONS.filter((action) => action.group === 'scroll')
export const NAV_ACTIONS = SHORTCUT_ACTIONS.filter((action) => action.group === 'nav')

export function shortcutAction(id: string): ShortcutAction | undefined {
	return SHORTCUT_ACTIONS.find((action) => action.id === id)
}