import { ScopedKey, type ServerScope } from "@/utils/server-scope"

const normalize = (directory: string) => directory.replace(/[\\/]+$/, "")

const key = (scope: ServerScope, directory: string) => ScopedKey.from(scope, normalize(directory))

type State =

| {

status: "pending"

}

| {

status: "ready"

}

| {

status: "failed"

message: string

}

const state = new Map<string, State>()

const waiters = new Map<

string,

{

promise: Promise<State>

resolve: (state: State) => void

}

>()

function deferred() {

const box = { resolve: (_: State) => {} }

const promise = new Promise<State>((resolve) => {

box.resolve = resolve

})

return { promise, resolve: box.resolve }

}

export const Worktree = {

get(scope: ServerScope, directory: string) {

return state.get(key(scope, directory))

},

pending(scope: ServerScope, directory: string) {

const id = key(scope, directory)

const current = state.get(id)

if (current && current.status !== "pending") return

state.set(id, { status: "pending" })

},

ready(scope: ServerScope, directory: string) {

const id = key(scope, directory)

const next = { status: "ready" } as const

state.set(id, next)

const waiter = waiters.get(id)

if (!waiter) return

waiters.delete(id)

waiter.resolve(next)

},

failed(scope: ServerScope, directory: string, message: string) {

const id = key(scope, directory)

const next = { status: "failed", message } as const

state.set(id, next)

const waiter = waiters.get(id)

if (!waiter) return

waiters.delete(id)

waiter.resolve(next)

},

wait(scope: ServerScope, directory: string) {

const id = key(scope, directory)

const current = state.get(id)

if (current && current.status !== "pending") return Promise.resolve(current)

const existing = waiters.get(id)

if (existing) return existing.promise

const waiter = deferred()

waiters.set(id, waiter)

return waiter.promise

},

}