package discriminator

// The heuristic crowdsec. It reads SWW_WAF_CROWDSEC_LAPI_URL, and the decisions
// through the reputation lists.

import (
	"context"
	"time"

	"sneak.berlin/go/smallwebwaf/internal/bans"
	"sneak.berlin/go/smallwebwaf/internal/config"
	"sneak.berlin/go/smallwebwaf/internal/reputation"
	"sneak.berlin/go/smallwebwaf/internal/requestlog"
)

// crowdSec refuses a request when a decision of the CrowdSec decision list on
// the client is in force at now. It then adds the tag crowdsec, notes the
// list, as noteHit does, and bans the client until that decision ends. Its
// figures are the decision's scenario and when it ends.
type crowdSec struct{}

func (crowdSec) name() string { return "crowdsec" }

func (crowdSec) check(_ context.Context, rq *request, now time.Time) *verdict {
	decision, listed := rq.crowdSecDecisionInForce(now)
	if !listed {
		return nil
	}

	rq.addTag(config.CrowdSecTag)
	rq.noteHit(bans.ReputationHit{Source: rq.h.config.CrowdSecDecisionsURL},
		"listed by the CrowdSec decision list")

	return &verdict{
		action: rq.banForCrowdSec(now, decision),
		figures: map[string]any{
			"scenario": decision.Scenario,
			"expires":  requestlog.FormatTime(decision.Expires),
		},
	}
}

// crowdSecDecisionInForce returns the decision of the CrowdSec decision list on
// the client that is in force at now, and reports whether there is one, which
// the heuristic crowdsec refuses the request for.
func (rq *request) crowdSecDecisionInForce(
	now time.Time,
) (reputation.Decision, bool) {
	return rq.h.lists.CrowdSecDecision(rq.client, now)
}