// This file is part of the happyDomain (R) project.
// Copyright (c) 2020-2026 happyDomain
// Authors: Pierre-Olivier Mercier, et al.

package checker

import (
	"sort"
	"sync"

	sdk "git.happydns.org/checker-sdk-go/checker"
)

// registry holds the rules and collectors that ship with the checker.
// Each rule/collector registers itself in an init() so that adding a new
// one is a single-file change — no central list to maintain.
var registry = struct {
	mu         sync.Mutex
	rules      []sdk.CheckRule
	collectors []Collector
}{}

// RegisterRule appends a rule to the global registry. Intended to be
// called from init() in each rule file.
func RegisterRule(r sdk.CheckRule) {
	registry.mu.Lock()
	defer registry.mu.Unlock()
	registry.rules = append(registry.rules, r)
}

// RegisterCollector appends a collector to the global registry. Reserved
// for step 4; the orchestrator currently wires only rootCollector
// directly.
func RegisterCollector(c Collector) {
	registry.mu.Lock()
	defer registry.mu.Unlock()
	registry.collectors = append(registry.collectors, c)
}

// Rules returns every registered rule, sorted by Name() so the output is
// stable across init-order changes (which Go does not guarantee between
// files).
func Rules() []sdk.CheckRule {
	registry.mu.Lock()
	out := make([]sdk.CheckRule, len(registry.rules))
	copy(out, registry.rules)
	registry.mu.Unlock()
	sort.Slice(out, func(i, j int) bool { return out[i].Name() < out[j].Name() })
	return out
}