import { test } from "node:test"
import assert from "node:assert/strict"
import { buildLiveOptimizerData, DEFAULT_ROUTE_AI_OPTIMIZER_SETTINGS, type OptimizerApiServer, type RouteOptimizerSpeedProbe } from "./route-optimizer-data"

// Independent legacy oracle: forced pick, original pool order, first equal total.
function legacy(wans: string[], pool: RouteOptimizerSpeedProbe[], now: number) {
  const score = (p: RouteOptimizerSpeedProbe, iface: string) => {
    const want=iface.trim().toLowerCase(), got=p.srcInterface.trim().toLowerCase()
    if(got && want && got!==want)return -1
    return (got&&want?100:!got&&want?35:!want&&got?15:5)
      +(p.lastPingRttMs!==null?20:0)+(p.lastTxAvgMbps!==null?10:0)+(p.lastRxAvgMbps!==null?10:0)
      +(p.lastPingAt?Math.max(0,20-Math.floor((now-Date.parse(p.lastPingAt))/3600000)):0)
  }
  let best=-Infinity, result: (string|null)[]=[]
  function visit(i:number,used:Set<string>,picked:(string|null)[],sum:number){
    if(i===wans.length){if(sum>best){best=sum;result=[...picked]}return}
    let matched=false
    for(const p of pool){if(used.has(p.id))continue;const value=score(p,wans[i]);if(value<0)continue
      matched=true;used.add(p.id);visit(i+1,used,[...picked,p.id],sum+value);used.delete(p.id)
    }
    if(!matched)visit(i+1,used,[...picked,null],sum)
  }
  visit(0,new Set(),[],0);return result
}

const common={host:"192.0.2.1",enabled:true,status:"online" as const,latency:10,country:"RU",site:"TEST",model:"CHR"}
function chosen(wans:string[],probes:RouteOptimizerSpeedProbe[]){
  const rows:OptimizerApiServer[]=[{...common,id:1,name:"Home",type:"home-router",wanUplinks:wans.map((iface,i)=>({id:`w${i}`,name:`WAN${i}`,iface,isp:"ISP",ip:"198.51.100.1",maxDl:100,maxUl:100}))},{...common,id:2,name:"Jump",type:"jump-host"}]
  return buildLiveOptimizerData(rows,[],DEFAULT_ROUTE_AI_OPTIMIZER_SETTINGS,probes).homes[0].wanJhLegs.map(leg=>leg.observed?.probeId??null)
}

function probe(i:number,iface:string):RouteOptimizerSpeedProbe{return {id:`p${i}`,srcServerId:"1",dstServerId:"2",srcInterface:iface,dstInterface:"",enabled:true,lastPingRttMs:10,lastPingLossPct:0,lastTxAvgMbps:100,lastRxAvgMbps:100,lastPingAt:null}}

test("branch bound preserves legacy assignments for ties, incompatibility and partial matching",context=>{
 const now=Date.parse("2026-10-04T12:00:00Z");context.mock.method(Date,"now",()=>now)
 let seed=917;const random=(n:number)=>{seed=(Math.imul(seed,1664525)+1013904223)>>>0;return (seed>>>8)%n}
 const names=["","ether1","ether2"," ETHER1 "]
 for(let fixture=0;fixture<1230;fixture++){
   const count=fixture<1200?1+random(4):7,wans=Array.from({length:count},()=>names[1+random(names.length-1)])
   const pool=Array.from({length:count+random(3)},(_,i)=>({...probe(i,names[random(names.length)]),lastPingRttMs:random(2)?0:null,lastTxAvgMbps:random(2)?100:null,lastRxAvgMbps:random(2)?100:null,lastPingAt:random(3)?null:"2026-10-04T10:00:00Z"}))
   assert.deepEqual(chosen(wans,pool),legacy(wans,pool,now),`fixture ${fixture}`)
 }
})

test("twenty equal wildcard probes keep the first seven in pool order",()=>{
 const wans=Array.from({length:7},(_,i)=>`ether${i}`),pool=Array.from({length:20},(_,i)=>probe(i,""))
 assert.deepEqual(chosen(wans,pool),Array.from({length:7},(_,i)=>`p${i}`))
})

test("early forced choice remains unchanged when a later WAN loses its compatible probe",()=>{
 const wans=["ether1", "ether1"],pool=[probe(0,"ether1"),probe(1,"ether2")]
 assert.deepEqual(chosen(wans,pool),["p0",null])
})


test("DFS uses one ranking time when the clock crosses an hour boundary",context=>{
 const at=Date.parse('2026-10-07T12:00:00Z');let calls=0;context.mock.method(Date,'now',()=>at+calls++*3600000)
 const pool=Array.from({length:3},(_,i)=>({...probe(i,''),lastPingAt:new Date(at-(2-i)*3600000).toISOString()}))
 assert.deepEqual(chosen(['ether1','ether2'],pool),legacy(['ether1','ether2'],pool,at))
})

test("greedy fallback remains unchanged for eight WANs and a short pool",()=>{
 const wans=Array.from({length:8},()=> 'ether1'),pool=[probe(0,'ether2'),probe(1,'ether1'),probe(2,''),probe(3,'')]
 assert.deepEqual(chosen(wans,pool),['p1','p2','p3',null,null,null,null,null])
})