package com.estateunified.panel

import java.util.UUID
import java.util.concurrent.ConcurrentHashMap

internal data class OtpRequest(
    val requestId: String,
    val phone: String,
    val createdAtMs: Long,
)

internal class OtpStore(
    val acceptedCode: String = System.getenv("PANEL_OTP_CODE")?.ifBlank { null } ?: "0000",
    private val ttlMs: Long = 5 * 60 * 1000L,
) {
    private val requests = ConcurrentHashMap<String, OtpRequest>()

    fun create(phone: String): OtpRequest {
        val req =
            OtpRequest(
                requestId = UUID.randomUUID().toString(),
                phone = normalizePhone(phone),
                createdAtMs = System.currentTimeMillis(),
            )
        requests[req.requestId] = req
        cleanup()
        return req
    }

    fun verify(
        phone: String,
        code: String,
    ): Boolean {
        cleanup()
        if (code.trim() != acceptedCode) return false
        val norm = normalizePhone(phone)
        return requests.values.any { it.phone == norm }
    }

    private fun normalizePhone(phone: String): String {
        val trimmed = phone.trim()
        if (!trimmed.startsWith("+")) return trimmed
        return "+" + trimmed.drop(1).replace("\\s+".toRegex(), "")
    }

    private fun cleanup() {
        val now = System.currentTimeMillis()
        val expired = requests.values.filter { now - it.createdAtMs > ttlMs }.map { it.requestId }
        expired.forEach { requests.remove(it) }
    }
}