import type { Organization, Project, Report, User, Version } from '@modrinth/utils'

type Thread = { id: string }

export type PlatformNotificationAction = {
	title: string
	action_route: [string, string]
}

export type PlatformNotificationBody = {
	project_id?: string
	version_id?: string
	report_id?: string
	thread_id?: string
	invited_by?: string
	organization_id?: string
}

export type PlatformNotification = {
	id: string
	user_id: string
	type: 'project_update' | 'team_invite' | 'status_change' | 'moderator_message'
	title: string
	text: string
	link: string
	read: boolean
	created: string
	actions: PlatformNotificationAction[]
	body?: PlatformNotificationBody
	extra_data?: Record<string, unknown>
	grouped_notifs?: PlatformNotification[]
}

async function getBulk<T extends { id: string }>(
	type: string,
	ids: string[],
	apiVersion = 2,
): Promise<T[]> {
	if (!ids || ids.length === 0) {
		return []
	}
	const url = `${type}?ids=${encodeURIComponent(JSON.stringify([...new Set(ids)]))}`
	try {
		const res = await useBaseFetch(url, { apiVersion })
		return Array.isArray(res) ? res : []
	} catch {
		return []
	}
}

export async function fetchExtraNotificationData(
	notifications: PlatformNotification[],
): Promise<PlatformNotification[]> {
	const bulk = {
		projects: [] as string[],
		reports: [] as string[],
		threads: [] as string[],
		users: [] as string[],
		versions: [] as string[],
		organizations: [] as string[],
	}

	for (const notification of notifications) {
		if (notification.body) {
			if (notification.body.project_id) bulk.projects.push(notification.body.project_id)
			if (notification.body.version_id) bulk.versions.push(notification.body.version_id)
			if (notification.body.report_id) bulk.reports.push(notification.body.report_id)
			if (notification.body.thread_id) bulk.threads.push(notification.body.thread_id)
			if (notification.body.invited_by) bulk.users.push(notification.body.invited_by)
			if (notification.body.organization_id)
				bulk.organizations.push(notification.body.organization_id)
		}
	}

	const reports = (await getBulk<Report>('reports', bulk.reports)).filter(Boolean)
	for (const r of reports) {
		if (!r?.item_type) continue
		if (r.item_type === 'project') bulk.projects.push(r.item_id)
		else if (r.item_type === 'user') bulk.users.push(r.item_id)
		else if (r.item_type === 'version') bulk.versions.push(r.item_id)
	}

	const versions = (await getBulk<Version>('versions', bulk.versions)).filter(Boolean)
	for (const v of versions) bulk.projects.push(v.project_id)

	const [projects, threads, users, organizations] = await Promise.all([
		getBulk<Project>('projects', bulk.projects),
		getBulk<Thread>('threads', bulk.threads),
		getBulk<User>('users', bulk.users),
		getBulk<Organization>('organizations', bulk.organizations, 3),
	])

	for (const n of notifications) {
		n.extra_data = {}
		if (n.body) {
			if (n.body.project_id)
				n.extra_data.project = projects.find((x) => x.id === n.body!.project_id)
			if (n.body.organization_id)
				n.extra_data.organization = organizations.find((x) => x.id === n.body!.organization_id)
			if (n.body.report_id) {
				n.extra_data.report = reports.find((x) => x.id === n.body!.report_id)
				const t = (n.extra_data.report as Report | undefined)?.item_type
				if (t === 'project')
					n.extra_data.project = projects.find(
						(x) => x.id === (n.extra_data?.report as Report | undefined)?.item_id,
					)
				else if (t === 'user')
					n.extra_data.user = users.find(
						(x) => x.id === (n.extra_data?.report as Report | undefined)?.item_id,
					)
				else if (t === 'version') {
					n.extra_data.version = versions.find(
						(x) => x.id === (n.extra_data?.report as Report | undefined)?.item_id,
					)
					n.extra_data.project = projects.find(
						(x) => x.id === (n.extra_data?.version as Version | undefined)?.project_id,
					)
				}
			}
			if (n.body.thread_id) n.extra_data.thread = threads.find((x) => x.id === n.body!.thread_id)
			if (n.body.invited_by)
				n.extra_data.invited_by = users.find((x) => x.id === n.body!.invited_by)
			if (n.body.version_id)
				n.extra_data.version = versions.find((x) => x.id === n.body!.version_id)
		}
	}
	return notifications
}

export function groupNotifications(notifications: PlatformNotification[]): PlatformNotification[] {
	const grouped: PlatformNotification[] = []
	for (let i = 0; i < notifications.length; i++) {
		const current = notifications[i]
		const next = notifications[i + 1]
		if (current.body && i < notifications.length - 1 && isSimilar(current, next)) {
			current.grouped_notifs = [next]
			let j = i + 2
			while (j < notifications.length && isSimilar(current, notifications[j])) {
				current.grouped_notifs.push(notifications[j])
				j++
			}
			grouped.push(current)
			i = j - 1
		} else {
			grouped.push(current)
		}
	}
	return grouped
}

function isSimilar(a: PlatformNotification, b: PlatformNotification | undefined): boolean {
	return !!a?.body?.project_id && a.body!.project_id === b?.body?.project_id
}

export async function markAsRead(
	ids: string[],
): Promise<(notifications: PlatformNotification[]) => PlatformNotification[]> {
	await useBaseFetch(`notifications?ids=${JSON.stringify([...new Set(ids)])}`, {
		method: 'PATCH',
	})
	return (notifications: PlatformNotification[]) => {
		const newNotifs = notifications ?? []
		newNotifs.forEach((n) => {
			if (ids.includes(n.id)) n.read = true
		})
		return newNotifs
	}
}