package httpserver

import (
	"context"
	"crypto/sha256"
	"encoding/json"
	"time"

	"git.yuntuo.hk/k2safe/orbit/internal/fault"
	core "git.yuntuo.hk/k2safe/orbit/model"
	"git.yuntuo.hk/k2safe/orbit/platform/auth"
	"git.yuntuo.hk/k2safe/orbit/pulse/worker"
)

type claimResult struct {
	assignment *worker.Assignment
	err        error
}

func workerPollKey(ns core.ID, in worker.ConnectInput) [32]byte {
	// 正式注册已校验；再次规范化仅取得稳定能力集合，不包含任何秘密。
	in, _ = worker.NormalizeConnect(in)
	raw, _ := json.Marshal(struct {
		Namespace, Queue core.ID
		Capabilities     []worker.Capability
		Keys             bool
	}{ns, in.QueueID, in.Capabilities, in.ConcurrencyKeys})
	return sha256.Sum256(raw)
}
func (h *WorkerHub) claimFair(ctx context.Context, t auth.Token, b worker.Binding, key [32]byte) (out claimResult) {
	// HTTP handler 原本具有 panic 隔离；异步领取同样不能因一次异常杀死其他连接。
	defer func() {
		if recover() != nil {
			out = claimResult{err: fault.Unavailable}
		}
	}()
	h.mu.Lock()
	until := h.emptyPolls[key]
	h.mu.Unlock()
	if until.After(time.Now()) {
		return out
	}
	call, stop := context.WithTimeout(ctx, 8*time.Second)
	defer stop()
	out.assignment, out.err = h.service.Claim(call, t, b)
	if out.assignment == nil && out.err == nil {
		h.mu.Lock()
		now := time.Now()
		for k, v := range h.emptyPolls {
			if !v.After(now) {
				delete(h.emptyPolls, k)
			}
		}
		if len(h.emptyPolls) < 128 {
			h.emptyPolls[key] = now.Add(h.poll)
		}
		h.mu.Unlock()
	}
	return out
}