import { computed, type ComputedRef } from 'vue'
import { useRoute } from 'vue-router'

export interface InstanceContext {
	isInInstance: ComputedRef<boolean>
	instanceId: ComputedRef<string | null>
	currentPage: ComputedRef<string | null>
}

export function useInstanceContext(): InstanceContext {
	const route = useRoute()

	const instanceId = computed<string | null>(() => {
		const param = route.params.id
		if (param && typeof param === 'string') return param

		const query = route.query.i
		if (query && typeof query === 'string') return query

		return null
	})

	const isInInstance = computed<boolean>(() => {
		// /instance/:id and all subroutes (Mods, Files, Worlds, Screenshots, Logs)
		if (route.path.startsWith('/instance/')) return true

		// /browse/:type?i=:id
		if (route.path.startsWith('/browse/') && route.query.i) return true

		// /project/:id?i=:id
		if (route.path.startsWith('/project/') && route.query.i) return true

		return false
	})

	const currentPage = computed<string | null>(() => {
		const segments = route.path.split('/').filter(Boolean)
		return segments[0] ?? null
	})

	return { isInInstance, instanceId, currentPage }
}