// Release Hub — zentraler Manifest-Aggregator für Patch-DB Agents
//
// Ziele
// - Zentrale Verwaltung mehrerer Agent-Endpunkte (Manifest-URLs)
// - Regelmäßiges Pullen/Parsen der Manifeste
// - Vereinheitlichte Release-Liste mit Filter-/Such-UI (Server-seitig gefiltert)
// - Reines Go (Standardbibliothek), ohne externe Cloud/CDN
// - Persistenz in lokalen JSON-Dateien (Agents + Cache)
// - REST-JSON-API (/api/releases, /api/agents)
//
// Starten
//   go run .
//
// Hinweis zum erwarteten Manifest-Format
// - Bevorzugt:
//   { "releases": [ { "version": "1.2.3", "released_at": "2025-10-01T10:00:00Z", ... } ] }
// - Alternativ: ein reines Array [ { ... }, { ... } ]
// - Außerdem unterstützt: verschachtelte JSON-Strukturen. Insbesondere das Schema
//   releases → branch → channel → arch → bitness → os → { release-obj }
//   wird erkannt und in flache Releases umgewandelt. Zusätzlich akzeptiert der Hub
//   gängige Alias-Felder (z. B. releasedAt/release_date/published_at → released_at,
//   size → size_bytes, sha256sum → sha256, ...).
// - Datumsformat: RFC3339, YYYY-MM-DD, oder Sekunden seit Epoch.
// - Bekannte Felder: version, build, released_at, branch, channel, os, arch, notes, assets[]
// - assets: { url, sha256, size_bytes, signature_url, content_type }

package main

import (
	"bytes"
	"encoding/json"
	"errors"
	"fmt"
	"html/template"
	"io"
	"log"
	"net/http"
	"os"
	"path/filepath"
	"sort"
	"strconv"
	"strings"
	"sync"
	"time"
	"unicode"
)

// ---- Datenmodell ------------------------------------------------------------

type Asset struct {
	URL          string `json:"url"`
	SHA256       string `json:"sha256"`
	Size         int64  `json:"size_bytes,omitempty"`
	SignatureURL string `json:"signature_url,omitempty"`
	ContentType  string `json:"content_type,omitempty"`
}

type FlexTime struct{ time.Time }

func (ft *FlexTime) UnmarshalJSON(b []byte) error {
	s := strings.Trim(string(b), "\"")
	if s == "" || s == "null" {
		return nil
	}
	// Versuche RFC3339, dann Datum-only
	if t, err := time.Parse(time.RFC3339, s); err == nil {
		ft.Time = t
		return nil
	}
	if t, err := time.Parse("2006-01-02", s); err == nil {
		ft.Time = t
		return nil
	}
	// Fallback: versuche seconds since epoch
	if sec, err := strconv.ParseInt(s, 10, 64); err == nil {
		ft.Time = time.Unix(sec, 0).UTC()
		return nil
	}
	return fmt.Errorf("unsupported time format: %q", s)
}

// Release ist die vereinheitlichte Sicht auf Agent-Releases.
// Felder sind konservativ gewählt, weitere können bei Bedarf ergänzt werden.
type Release struct {
	Version    string   `json:"version"`
	Build      string   `json:"build,omitempty"`
	ReleasedAt FlexTime `json:"released_at"`
	Branch     string   `json:"branch,omitempty"`
	Channel    string   `json:"channel,omitempty"`
	OS         string   `json:"os,omitempty"`
	Arch       string   `json:"arch,omitempty"`
	Notes      string   `json:"notes,omitempty"`
	Vendor     string   `json:"vendor,omitempty"`
	Product    string   `json:"product,omitempty"`
	Assets     []Asset  `json:"assets,omitempty"`

	// Quelle (wird vom Hub gesetzt)
	AgentID   string `json:"agent_id"`
	AgentName string `json:"agent_name"`
}

// ManifestEnvelope erlaubt sowohl {"releases": [...] } als auch reines Array
// zu dekodieren.
type ManifestEnvelope struct {
	Releases []Release `json:"releases"`
}

// Agent beschreibt einen registrierten Manifest-Endpunkt.
type Agent struct {
	ID           string    `json:"id"`
	Name         string    `json:"name"`
	EndpointURL  string    `json:"endpoint_url"`
	Enabled      bool      `json:"enabled"`
	LastOK       time.Time `json:"last_ok,omitempty"`
	LastError    string    `json:"last_error,omitempty"`
	ETag         string    `json:"etag,omitempty"`
	LastModified string    `json:"last_modified,omitempty"`
}

// ---- Persistence ------------------------------------------------------------

type Store struct {
	mu       sync.RWMutex
	agents   map[string]*Agent
	releases []Release // zusammengeführte, letzte erfolgreiche Pulls

	dataDir string
}

func NewStore(dataDir string) *Store {
	return &Store{
		agents:  make(map[string]*Agent),
		dataDir: dataDir,
	}
}

func (s *Store) load() error {
	if err := os.MkdirAll(s.dataDir, 0o755); err != nil {
		return err
	}

	// Agents
	b, err := os.ReadFile(filepath.Join(s.dataDir, "agents.json"))
	if err == nil {
		var list []*Agent
		if err := json.Unmarshal(b, &list); err != nil {
			return err
		}
		for _, a := range list {
			s.agents[a.ID] = a
		}
	}

	// Releases Cache
	b, err = os.ReadFile(filepath.Join(s.dataDir, "releases-cache.json"))
	if err == nil {
		var rr []Release
		if err := json.Unmarshal(b, &rr); err != nil {
			return err
		}
		s.releases = rr
	}
	return nil
}

func (s *Store) saveAgents() error {
	s.mu.RLock()
	defer s.mu.RUnlock()
	list := make([]*Agent, 0, len(s.agents))
	for _, a := range s.agents {
		list = append(list, a)
	}
	sort.Slice(list, func(i, j int) bool { return list[i].Name < list[j].Name })
	b, _ := json.MarshalIndent(list, "", "  ")
	return os.WriteFile(filepath.Join(s.dataDir, "agents.json"), b, 0o644)
}

func (s *Store) saveReleases() error {
	s.mu.RLock()
	defer s.mu.RUnlock()
	b, _ := json.MarshalIndent(s.releases, "", "  ")
	return os.WriteFile(filepath.Join(s.dataDir, "releases-cache.json"), b, 0o644)
}

// ---- Fetching ---------------------------------------------------------------

type Fetcher struct {
	client   *http.Client
	store    *Store
	interval time.Duration
	stopCh   chan struct{}
}

func NewFetcher(store *Store, interval time.Duration) *Fetcher {
	return &Fetcher{
		client:   &http.Client{Timeout: 20 * time.Second},
		store:    store,
		interval: interval,
		stopCh:   make(chan struct{}),
	}
}

func (f *Fetcher) Start() {
	go func() {
		// Initial sofortiger Lauf
		f.FetchOnce()
		ticker := time.NewTicker(f.interval)
		defer ticker.Stop()
		for {
			select {
			case <-ticker.C:
				f.FetchOnce()
			case <-f.stopCh:
				return
			}
		}
	}()
}

func (f *Fetcher) Stop() { close(f.stopCh) }

func (f *Fetcher) FetchOnce() {
	f.store.mu.RLock()
	agents := make([]*Agent, 0, len(f.store.agents))
	for _, a := range f.store.agents {
		if a.Enabled {
			agents = append(agents, a)
		}
	}
	f.store.mu.RUnlock()

	var all []Release
	var mu sync.Mutex
	var wg sync.WaitGroup

	for _, a := range agents {
		a := a
		wg.Add(1)
		go func() {
			defer wg.Done()
			rels, err := f.fetchAgent(a)
			if err != nil {
				log.Printf("fetch agent %s: %v", a.Name, err)
				f.store.mu.Lock()
				a.LastError = err.Error()
				f.store.mu.Unlock()
				return
			}
			for i := range rels {
				rels[i].AgentID = a.ID
				rels[i].AgentName = a.Name
			}
			mu.Lock()
			all = append(all, rels...)
			mu.Unlock()

			f.store.mu.Lock()
			a.LastError = ""
			a.LastOK = time.Now().UTC()
			f.store.mu.Unlock()
		}()
	}

	wg.Wait()

	// Vereinheitlichte Sortierung: neueste zuerst
	sort.Slice(all, func(i, j int) bool {
		return all[i].ReleasedAt.Time.After(all[j].ReleasedAt.Time)
	})

	f.store.mu.Lock()
	f.store.releases = all
	f.store.mu.Unlock()

	_ = f.store.saveReleases()
}

func (f *Fetcher) fetchAgent(a *Agent) ([]Release, error) {
	req, err := http.NewRequest(http.MethodGet, a.EndpointURL, nil)
	if err != nil {
		return nil, err
	}
	if a.ETag != "" {
		req.Header.Set("If-None-Match", a.ETag)
	}
	if a.LastModified != "" {
		req.Header.Set("If-Modified-Since", a.LastModified)
	}

	resp, err := f.client.Do(req)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	if resp.StatusCode == http.StatusNotModified {
		f.store.mu.RLock()
		var cached []Release
		for _, r := range f.store.releases {
			if r.AgentID == a.ID {
				cached = append(cached, r)
			}
		}
		f.store.mu.RUnlock()
		return cached, nil
	}

	if resp.StatusCode != http.StatusOK {
		b, _ := io.ReadAll(io.LimitReader(resp.Body, 2048))
		return nil, fmt.Errorf("unexpected status %s: %s", resp.Status, string(b))
	}

	if et := resp.Header.Get("ETag"); et != "" {
		a.ETag = et
	}
	if lm := resp.Header.Get("Last-Modified"); lm != "" {
		a.LastModified = lm
	}

	raw, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}

	// 1) {"releases": [...]}
	var env ManifestEnvelope
	if err := json.Unmarshal(raw, &env); err == nil && len(env.Releases) > 0 {
		return env.Releases, nil
	}

	// 2) Direktes Array
	var list []Release
	if err := json.Unmarshal(raw, &list); err == nil && len(list) > 0 {
		return list, nil
	}

	// 3) Generisch durchsuchen (beliebig verschachtelt, Aliasse normalisieren)
	if rr, err := parseAnyReleases(raw); err == nil && len(rr) > 0 {
		return cleanReleases(rr), nil
	}

	return nil, errors.New("unrecognized manifest format: expected 'releases' or array")
}

// ---- Filtering & Query ------------------------------------------------------

type ReleaseFilter struct {
	Q       string
	Channel string
	Branch  string
	OS      string
	Arch    string
	Vendor  string
	Product string
	From    time.Time
	To      time.Time
}

func (f ReleaseFilter) match(r Release) bool {
	if f.Q != "" {
		q := strings.ToLower(f.Q)
		hay := strings.ToLower(strings.Join([]string{
			r.Version, r.Build, r.Branch, r.Channel, r.OS, r.Arch, r.Notes, r.Vendor, r.Product, r.AgentName,
		}, ""))
		if !strings.Contains(hay, q) {
			return false
		}
	}
	if f.Channel != "" && !equalFoldOrDash(r.Channel, f.Channel) {
		return false
	}
	if f.Branch != "" && !equalFoldOrDash(r.Branch, f.Branch) {
		return false
	}
	if f.OS != "" && !equalFoldOrDash(r.OS, f.OS) {
		return false
	}
	if f.Arch != "" && !equalFoldOrDash(r.Arch, f.Arch) {
		return false
	}
	if f.Vendor != "" && !equalFoldOrDash(r.Vendor, f.Vendor) {
		return false
	}
	if f.Product != "" && !equalFoldOrDash(r.Product, f.Product) {
		return false
	}
	if !f.From.IsZero() && r.ReleasedAt.Time.Before(f.From) {
		return false
	}
	if !f.To.IsZero() && r.ReleasedAt.Time.After(f.To) {
		return false
	}
	return true
}

func equalFoldOrDash(a, b string) bool {
	a = strings.TrimSpace(a)
	b = strings.TrimSpace(b)
	if a == "" && (b == "-" || b == "") {
		return true
	}
	if b == "" && (a == "-" || a == "") {
		return true
	}
	return strings.EqualFold(a, b)
}

// ---- HTTP/UI ---------------------------------------------------------------

type Server struct {
	store   *Store
	fetcher *Fetcher
	tz      *time.Location
}

func NewServer(store *Store, fetcher *Fetcher) *Server {
	tz, _ := time.LoadLocation("Europe/Berlin")
	return &Server{store: store, fetcher: fetcher, tz: tz}
}

func (s *Server) routesAdmin(mux *http.ServeMux) {
	mux.HandleFunc("/", s.handlerList(false))
	mux.HandleFunc("/agents", s.handleAgents)
	mux.HandleFunc("/agents/add", s.handleAgentAdd)
	mux.HandleFunc("/agents/toggle", s.handleAgentToggle)
	mux.HandleFunc("/agents/delete", s.handleAgentDelete)
	mux.HandleFunc("/refresh", s.handleRefresh)

	mux.HandleFunc("/api/releases", s.handleAPIReleases)
	mux.HandleFunc("/api/agents", s.handleAPIAgents)
	mux.HandleFunc("/healthz", s.handleHealth)
}

func (s *Server) routesPublic(mux *http.ServeMux) {
	// Read-only Oberfläche, keine Admin- oder API-Endpunkte
	mux.HandleFunc("/", s.handlerList(true))
	mux.HandleFunc("/healthz", s.handleHealth)
}

func (s *Server) handleRefresh(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
		return
	}
	go s.fetcher.FetchOnce()
	http.Redirect(w, r, "/", http.StatusSeeOther)
}

func (s *Server) handleAPIReleases(w http.ResponseWriter, r *http.Request) {
	s.store.mu.RLock()
	rels := append([]Release(nil), s.store.releases...)
	s.store.mu.RUnlock()

	// Optional Filter über Query-Params
	rf := parseFilter(r)
	out := make([]Release, 0, len(rels))
	for _, v := range rels {
		if rf.match(v) {
			out = append(out, v)
		}
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(out)
}

func (s *Server) handleAPIAgents(w http.ResponseWriter, r *http.Request) {
	s.store.mu.RLock()
	list := make([]*Agent, 0, len(s.store.agents))
	for _, a := range s.store.agents {
		list = append(list, a)
	}
	s.store.mu.RUnlock()

	sort.Slice(list, func(i, j int) bool { return list[i].Name < list[j].Name })

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(list)
}

func parseFilter(r *http.Request) ReleaseFilter {
	q := strings.TrimSpace(r.URL.Query().Get("q"))
	ch := strings.TrimSpace(r.URL.Query().Get("channel"))
	br := strings.TrimSpace(r.URL.Query().Get("branch"))
	osv := strings.TrimSpace(r.URL.Query().Get("os"))
	ar := strings.TrimSpace(r.URL.Query().Get("arch"))
	vndr := strings.TrimSpace(r.URL.Query().Get("vendor"))
	prd := strings.TrimSpace(r.URL.Query().Get("product"))

	var from, to time.Time
	if v := strings.TrimSpace(r.URL.Query().Get("from")); v != "" {
		from, _ = time.Parse("2006-01-02", v)
	}
	if v := strings.TrimSpace(r.URL.Query().Get("to")); v != "" {
		to, _ = time.Parse("2006-01-02", v)
		if !to.IsZero() {
			to = to.Add(24 * time.Hour).Add(-time.Nanosecond)
		}
	}

	return ReleaseFilter{Q: q, Channel: ch, Branch: br, OS: osv, Arch: ar, Vendor: vndr, Product: prd, From: from, To: to}
}

func (s *Server) handlerList(readOnly bool) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		rf := parseFilter(r)

		s.store.mu.RLock()
		rels := append([]Release(nil), s.store.releases...)
		s.store.mu.RUnlock()

		filtered := make([]Release, 0, len(rels))
		for _, v := range rels {
			if rf.match(v) {
				filtered = append(filtered, v)
			}
		}

		data := struct {
			Releases                                      []Release
			CountTotal                                    int
			CountShown                                    int
			Q, Channel, Branch, OS, Arch, Vendor, Product string
			From, To                                      string
			Now                                           string
			BaseStyle                                     string
			ReadOnly                                      bool
		}{
			Releases:   filtered,
			CountTotal: len(rels),
			CountShown: len(filtered),
			Q:          rf.Q, Channel: rf.Channel, Branch: rf.Branch, OS: rf.OS, Arch: rf.Arch, Vendor: rf.Vendor, Product: rf.Product,
			From: dateStr(rf.From), To: dateStr(rf.To),
			Now:       time.Now().In(s.tz).Format("02.01.2006 15:04 MST"),
			BaseStyle: baseStyle,
			ReadOnly:  readOnly,
		}

		var buf bytes.Buffer
		if err := pageTmpl.Execute(&buf, data); err != nil {
			http.Error(w, err.Error(), 500)
			return
		}
		w.Header().Set("Content-Type", "text/html; charset=utf-8")
		w.Write(buf.Bytes())
	}
}

func (s *Server) handleAgents(w http.ResponseWriter, r *http.Request) {
	s.store.mu.RLock()
	list := make([]*Agent, 0, len(s.store.agents))
	for _, a := range s.store.agents {
		list = append(list, a)
	}
	s.store.mu.RUnlock()
	sort.Slice(list, func(i, j int) bool { return list[i].Name < list[j].Name })

	var buf bytes.Buffer
	if err := agentsTmpl.Execute(&buf, struct{ Agents []*Agent }{list}); err != nil {
		http.Error(w, err.Error(), 500)
		return
	}
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	w.Write(buf.Bytes())
}

func (s *Server) handleAgentAdd(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
		return
	}
	name := strings.TrimSpace(r.FormValue("name"))
	url := strings.TrimSpace(r.FormValue("url"))
	if name == "" || url == "" {
		http.Error(w, "name and url required", 400)
		return
	}

	id := genID()
	a := &Agent{ID: id, Name: name, EndpointURL: url, Enabled: true}
	s.store.mu.Lock()
	s.store.agents[a.ID] = a
	s.store.mu.Unlock()
	_ = s.store.saveAgents()
	go s.fetcher.FetchOnce()
	http.Redirect(w, r, "/agents", http.StatusSeeOther)
}

func (s *Server) handleAgentToggle(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
		return
	}
	id := strings.TrimSpace(r.FormValue("id"))

	s.store.mu.Lock()
	a, ok := s.store.agents[id]
	if !ok {
		s.store.mu.Unlock()
		http.Error(w, "not found", 404)
		return
	}
	a.Enabled = !a.Enabled
	s.store.mu.Unlock() // ⚠️ Vor saveAgents entsperren, sonst Deadlock mit RWMutex

	_ = s.store.saveAgents()
	http.Redirect(w, r, "/agents", http.StatusSeeOther)
}

func (s *Server) handleAgentDelete(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
		return
	}
	id := strings.TrimSpace(r.FormValue("id"))
	s.store.mu.Lock()
	delete(s.store.agents, id)
	s.store.mu.Unlock()
	_ = s.store.saveAgents()

	// Entferne Releases dieses Agents aus Cache
	s.store.mu.Lock()
	filtered := s.store.releases[:0]
	for _, r := range s.store.releases {
		if r.AgentID != id {
			filtered = append(filtered, r)
		}
	}
	s.store.releases = filtered
	s.store.mu.Unlock()
	_ = s.store.saveReleases()

	http.Redirect(w, r, "/agents", http.StatusSeeOther)
}

// ---- Utils -----------------------------------------------------------------

// parseAnyReleases durchsucht beliebig verschachtelte JSON-Strukturen nach Arrays von
// Release-ähnlichen Objekten. Gefundene Objekte werden hinsichtlich bekannter Alias-Felder
// normalisiert und dann in []Release dekodiert.
func parseAnyReleases(raw []byte) ([]Release, error) {
	var v any
	if err := json.Unmarshal(raw, &v); err != nil {
		return nil, err
	}

	// 3a) Spezielles hierarchisches SEND.NRW-Schema (releases→branch→channel→arch→bit→os→obj)
	if arr := parseHierarchicalFromRoot(v); len(arr) > 0 {
		b, _ := json.Marshal(arr)
		var rr []Release
		if err := json.Unmarshal(b, &rr); err == nil && len(rr) > 0 {
			return rr, nil
		}
	}

	// 3b) Generisch: beliebige Arrays von Objekt-Maps einsammeln und normalisieren
	var buckets [][]map[string]any
	collectObjectArrays(v, &buckets)
	var all []Release
	for _, arr := range buckets {
		norm := normalizeReleaseSlice(arr)
		b, _ := json.Marshal(norm)
		var rr []Release
		if err := json.Unmarshal(b, &rr); err == nil {
			keep := 0
			for _, r := range rr {
				if r.Version != "" || len(r.Assets) > 0 {
					keep++
				}
			}
			if keep > 0 {
				all = append(all, rr...)
			}
		}
	}
	return all, nil
}

// parseHierarchicalFromRoot erkennt Strukturen vom Typ
//
//	releases → branch → channel → arch → bitness → os → { release-obj }
//
// und liefert normalisierte Release-Maps zurück.
func parseHierarchicalFromRoot(root any) []map[string]any {
	m, ok := root.(map[string]any)
	if !ok {
		return nil
	}

	var defBranch, defChannel, defVendor, defProduct string
	if s, ok := m["default_branch"].(string); ok {
		defBranch = s
	}
	if s, ok := m["default_channel"].(string); ok {
		defChannel = s
	}
	if s, ok := m["vendor"].(string); ok {
		defVendor = s
	}
	if s, ok := m["product"].(string); ok {
		defProduct = s
	}

	relRoot, ok := m["releases"].(map[string]any)
	if !ok {
		return nil
	}

	out := make([]map[string]any, 0)
	for branchKey, channelsV := range relRoot {
		channels, ok := channelsV.(map[string]any)
		if !ok {
			continue
		}
		bk := branchKey
		if bk == "" {
			bk = defBranch
		}
		for channelKey, archsV := range channels {
			archs, ok := archsV.(map[string]any)
			if !ok {
				continue
			}
			ck := channelKey
			if ck == "" {
				ck = defChannel
			}
			for archKey, bitsV := range archs {
				bits, ok := bitsV.(map[string]any)
				if !ok {
					continue
				}
				ak := archKey
				for _, osesV := range bits {
					oses, ok := osesV.(map[string]any)
					if !ok {
						continue
					}
					for osKey, leafV := range oses {
						leaf, ok := leafV.(map[string]any)
						if !ok {
							continue
						}
						nm := normalizeReleaseMap(leaf)
						if _, ok := nm["branch"]; !ok && bk != "" {
							nm["branch"] = bk
						}
						if _, ok := nm["channel"]; !ok && ck != "" {
							nm["channel"] = ck
						}
						if _, ok := nm["arch"]; !ok && ak != "" {
							nm["arch"] = ak
						}
						if _, ok := nm["os"]; !ok && osKey != "" {
							nm["os"] = osKey
						}
						if _, ok := nm["vendor"]; !ok && defVendor != "" {
							nm["vendor"] = defVendor
						}
						if _, ok := nm["product"]; !ok && defProduct != "" {
							nm["product"] = defProduct
						}
						out = append(out, nm)
					}
				}
			}
		}
	}
	return out
}

func collectObjectArrays(v any, out *[][]map[string]any) {
	switch x := v.(type) {
	case []any:
		// Prüfe, ob es ein Array von Objekten ist
		var objArr []map[string]any
		ok := true
		for _, e := range x {
			m, isObj := e.(map[string]any)
			if !isObj {
				ok = false
				break
			}
			objArr = append(objArr, m)
		}
		if ok && len(objArr) > 0 {
			*out = append(*out, objArr)
		}
		// Rekursiv weitersuchen
		for _, e := range x {
			collectObjectArrays(e, out)
		}
	case map[string]any:
		for _, e := range x {
			collectObjectArrays(e, out)
		}
	}
}

func normalizeReleaseSlice(arr []map[string]any) []map[string]any {
	out := make([]map[string]any, 0, len(arr))
	for _, m := range arr {
		out = append(out, normalizeReleaseMap(m))
	}
	return out
}

func normalizeReleaseMap(m map[string]any) map[string]any {
	// Keys in snake_case bringen & Aliasse mappen
	out := make(map[string]any, len(m))
	for k, v := range m {
		out[camelToSnake(k)] = v
	}

	alias := func(dst string, alts ...string) {
		if _, ok := out[dst]; ok {
			return
		}
		for _, a := range alts {
			if val, ok := out[a]; ok {
				out[dst] = val
				return
			}
		}
	}

	// Release-Felder
	alias("version", "ver", "v")
	alias("build", "build_id")
	alias("released_at", "release_date", "releasedAt", "published_at", "publish_date", "date", "time", "timestamp")
	alias("branch", "br")
	alias("channel", "chan")
	alias("os", "platform")
	alias("arch", "architecture")
	alias("notes", "changelog", "summary")

	// Assets normalisieren (falls vorhanden)
	if raw, ok := out["assets"].([]any); ok {
		var aset []map[string]any
		for _, e := range raw {
			if am, ok := e.(map[string]any); ok {
				aset = append(aset, normalizeAssetMap(am))
			}
		}
		out["assets"] = aset
	}

	return out
}

func cleanReleases(in []Release) []Release {
	for i := range in {
		for j := range in[i].Assets {
			if in[i].Assets[j].SHA256 == "-" {
				in[i].Assets[j].SHA256 = ""
			}
			if in[i].Assets[j].SignatureURL == "-" {
				in[i].Assets[j].SignatureURL = ""
			}
		}
	}
	return in
}

func normalizeAssetMap(m map[string]any) map[string]any {
	out := make(map[string]any, len(m))
	for k, v := range m {
		out[camelToSnake(k)] = v
	}
	alias := func(dst string, alts ...string) {
		if _, ok := out[dst]; ok {
			return
		}
		for _, a := range alts {
			if val, ok := out[a]; ok {
				out[dst] = val
				return
			}
		}
	}
	alias("url", "href", "link")
	alias("sha256", "sha256sum", "checksum", "hash")
	alias("size_bytes", "size", "bytes")
	alias("signature_url", "sig", "signature", "signatureUrl")
	alias("content_type", "mime", "mimetype", "type")
	return out
}

func camelToSnake(s string) string {
	// sehr einfacher CamelCase→snake_case Konverter
	var b strings.Builder
	for i, r := range s {
		if unicode.IsUpper(r) {
			if i > 0 {
				b.WriteByte('_')
			}
			b.WriteRune(unicode.ToLower(r))
		} else {
			b.WriteRune(r)
		}
	}
	return b.String()
}

func genID() string {
	// simple time-based id, ausreichend für lokale Tooling-Zwecke
	return fmt.Sprintf("a_%d", time.Now().UnixNano())
}

func dateStr(t time.Time) string {
	if t.IsZero() {
		return ""
	}
	return t.Format("2006-01-02")
}

// ---- Templates & Styles (inline, keine externen CDNs) ----------------------

var baseStyle = `
:root{--bg:#0b1324;--card:#111a30;--muted:#93a0b0;--txt:#e9eef7;--acc:#4cc9f0;--ok:#22c55e;--warn:#f59e0b;--err:#ef4444}
*{box-sizing:border-box} body{margin:0;font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,"Helvetica Neue";background:var(--bg);color:var(--txt)}
.header{position:sticky;top:0;z-index:10;background:linear-gradient(90deg,#0b1324,#0e1a33);border-bottom:1px solid #1c2947;padding:16px}
.container{max-width:90%;margin:0 auto;padding:16px}
.card{background:var(--card);border:1px solid #1c2947;border-radius:16px;box-shadow:0 6px 18px rgba(0,0,0,.25)}
.row{display:flex;gap:12px;flex-wrap:wrap}
.btn{display:inline-block;padding:10px 14px;border-radius:12px;border:1px solid #2a3a63;background:#152448;color:var(--txt);text-decoration:none;cursor:pointer}
.btn:hover{background:#19305a}
.btn-acc{border-color:#2b9bc2}
.badge{padding:2px 8px;border-radius:999px;border:1px solid #2a3a63;color:var(--muted);font-size:12px}
.input, select{background:#0b1429;border:1px solid #2a3a63;border-radius:12px;padding:10px;color:var(--txt);width:100%}
label{font-size:12px;color:var(--muted)}
.table{width:100%;border-collapse:separate;border-spacing:0}
.table th, .table td{padding:10px 12px;border-bottom:1px solid #1c2947}
.table th{position:sticky;top:0;background:#122042;text-align:left}
.kv{display:grid;grid-template-columns:120px 1fr;gap:6px 12px}
.small{font-size:12px;color:var(--muted)}
.code{font-family:ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;font-size:12px}
hr{border:0;border-top:1px solid #1c2947;margin:12px 0}
`

var pageTmpl = template.Must(template.New("page").Funcs(template.FuncMap{
	"fmtTime": func(t FlexTime) string {
		if t.IsZero() {
			return ""
		}
		return t.Time.Format("02.01.2006 15:04")
	},
}).Parse(`<!doctype html>
<html lang="de">
<head>
<meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1">
<title>Release Hub</title>
<style>` + baseStyle + `</style>
</head>
<body>
<div class="header">
  <div class="container row" style="justify-content:space-between;align-items:center">
    <div>
      <div style="font-weight:700;font-size:18px">Release Hub</div>
      <div class="small">Unified Release · Version from: {{.Now}}</div>
    </div>
    {{if .ReadOnly}}
    <div></div>
    {{else}}
    <form class="row" action="/refresh" method="post">
      <button class="btn btn-acc" title="Reload now!">↻ Refresh Data</button>
      <a class="btn" href="/agents">⚙ Agents</a>
    </form>
    {{end}}
  </div>
</div>

<div class="container">
  <div class="card" style="padding:12px">
    <form class="row" method="get" action="/">
      <div style="flex:2;min-width:220px">
        <label>Search</label>
        <input class="input" name="q" value="{{.Q}}" placeholder="Version, Branch, Channel, Agent, Notizen…">
      </div>
      <div style="flex:1;min-width:140px"><label>Channel</label><input class="input" name="channel" value="{{.Channel}}" placeholder="stable/beta…"></div>
      <div style="flex:1;min-width:140px"><label>Branch</label><input class="input" name="branch" value="{{.Branch}}" placeholder="main/12.x…"></div>
      <div style="flex:1;min-width:160px"><label>Vendor</label><input class="input" name="vendor" value="{{.Vendor}}" placeholder="Mozilla"></div>
      <div style="flex:1;min-width:160px"><label>Product</label><input class="input" name="product" value="{{.Product}}" placeholder="Firefox"></div>
      <div style="flex:1;min-width:120px"><label>OS</label><input class="input" name="os" value="{{.OS}}" placeholder="windows/linux/macos"></div>
      <div style="flex:1;min-width:120px"><label>Arch</label><input class="input" name="arch" value="{{.Arch}}" placeholder="amd64/arm64…"></div>
      <div style="flex:1;min-width:130px"><label>From</label><input type="date" class="input" name="from" value="{{.From}}"></div>
      <div style="flex:1;min-width:130px"><label>To</label><input type="date" class="input" name="to" value="{{.To}}"></div>
      <div style="align-self:end"><button class="btn btn-acc">Filter</button></div>
    </form>
  </div>

  <div style="margin-top:12px" class="small">Show {{.CountShown}} from {{.CountTotal}} Releases</div>

  <div class="card" style="margin-top:8px; overflow:auto; max-height:70vh">
    <table class="table">
      <thead>
        <tr>
          <th>Date</th>
          <th>Version</th>
          <th>Branch</th>
          <th>Channel</th>
          <th>OS</th>
          <th>Arch</th>
          <th>Vendor</th>
          <th>Product</th>
          <th>Agent</th>
          <th>Assets</th>
          <th>Notes</th>
        </tr>
      </thead>
      <tbody>
      {{range .Releases}}
        <tr>
          <td>{{fmtTime .ReleasedAt}}</td>
          <td><span class="badge">{{.Version}}</span> {{if .Build}}<span class="small">({{.Build}})</span>{{end}}</td>
          <td>{{.Branch}}</td>
          <td>{{.Channel}}</td>
          <td>{{.OS}}</td>
          <td>{{.Arch}}</td>
          <td class="small">{{.Vendor}}</td>
          <td class="small">{{.Product}}</td>
          <td class="small">{{.AgentName}}</td>
          <td>
            {{if .Assets}}
              <div class="kv small">
                {{range .Assets}}
                  <div>Asset</div>
                  <div><a class="btn" href="{{.URL}}">Download</a> <span class="code">{{.ContentType}}</span> {{if .Size}}· {{.Size}} B{{end}} {{if .SHA256}}· sha256:{{.SHA256}}{{end}}</div>
                {{end}}
              </div>
            {{else}}
              <span class="small">-</span>
            {{end}}
          </td>
          <td class="small">{{.Notes}}</td>
        </tr>
      {{end}}
      </tbody>
    </table>
  </div>
</div>
</body>
</html>
`))

var agentsTmpl = template.Must(template.New("agents").Parse(`<!doctype html>
<html lang="de">
<head>
<meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1">
<title>Agents · Release Hub</title>
<style>` + baseStyle + `</style>
</head>
<body>
<div class="header">
  <div class="container row" style="justify-content:space-between;align-items:center">
    <div>
      <div style="font-weight:700;font-size:18px">Agenten</div>
      <div class="small">Manage Manifest-Endpoint</div>
    </div>
    <div>
      <a class="btn" href="/">← Overview</a>
    </div>
  </div>
</div>

<div class="container">
  <div class="card" style="padding:12px">
    <form class="row" method="post" action="/agents/add">
      <div style="flex:1;min-width:220px"><label>Name</label><input class="input" name="name" placeholder="eg. Mozilla Firefox"></div>
      <div style="flex:3;min-width:360px"><label>Manifest-URL</label><input class="input" name="url" placeholder="https://agent.local/v1/manifest"></div>
      <div style="align-self:end"><button class="btn btn-acc">Add</button></div>
    </form>
  </div>

  <div class="card" style="margin-top:12px">
    <table class="table">
      <thead><tr><th>Name</th><th>URL</th><th>Status</th><th>Actions</th></tr></thead>
      <tbody>
      {{range .Agents}}
        <tr>
          <td>{{.Name}}</td>
          <td class="small">{{.EndpointURL}}</td>
          <td class="small">
            {{if .Enabled}}<span class="badge" style="border-color:#2c6">active{{else}}<span class="badge" style="border-color:#666">inactive{{end}}</span>
            {{if .LastOK}}· OK: {{.LastOK}}{{end}} {{if .LastError}}· Error: {{.LastError}}{{end}}
          </td>
          <td>
            <form style="display:inline" method="post" action="/agents/toggle">
              <input type="hidden" name="id" value="{{.ID}}">
              <button class="btn">{{if .Enabled}}Deactivate{{else}}Activate{{end}}</button>
            </form>
            <form style="display:inline" method="post" action="/agents/delete" onsubmit="return confirm('Confirm Agent delete?')">
              <input type="hidden" name="id" value="{{.ID}}">
              <button class="btn" style="border-color:#a33">Delete</button>
            </form>
          </td>
        </tr>
      {{end}}
      </tbody>
    </table>
  </div>
</div>
</body>
</html>
`))

// ---- main ------------------------------------------------------------------

func getenv(k, d string) string {
	if v := os.Getenv(k); v != "" {
		return v
	}
	return d
}

func getduration(k string, d time.Duration) time.Duration {
	v, ok := os.LookupEnv(k)
	if !ok {
		return d
	}
	v = strings.TrimSpace(v)
	if v == "" {
		return d
	}
	if dur, err := time.ParseDuration(v); err == nil {
		return dur
	}
	if n, err := strconv.ParseInt(v, 10, 64); err == nil {
		return time.Duration(n) * time.Second
	}
	return d
}

func enabled(k string, def bool) bool {
	b, err := strconv.ParseBool(strings.ToLower(os.Getenv(k)))
	if err != nil {
		return def
	}
	return b
}

func main() {
	//flag.Parse()

	envAddr := getenv("HTTP_ADMIN", ":9090")
	envPublicAddr := getenv("HTTP_PUBLIC", ":8080")
	envDataDir := getenv("APP_DATADIR", "/data")
	envRefresh := getduration("APP_REFRESH", 10*time.Minute)

	store := NewStore(envDataDir)
	if err := store.load(); err != nil {
		log.Fatalf("load store: %v", err)
	}

	fetcher := NewFetcher(store, envRefresh)
	fetcher.Start()
	defer fetcher.Stop()

	srv := NewServer(store, fetcher)

	// Admin-Server
	muxAdmin := http.NewServeMux()
	srv.routesAdmin(muxAdmin)

	errCh := make(chan error, 2)
	go func() {
		log.Printf("Admin (voll) listening on %s", envAddr)
		errCh <- http.ListenAndServe(envAddr, muxAdmin)
	}()

	// Öffentlicher Read-only-Server (optional)
	if envPublicAddr != "" {
		muxPublic := http.NewServeMux()
		srv.routesPublic(muxPublic)
		go func() {
			log.Printf("Public (read-only) listening on %s", envPublicAddr)
			errCh <- http.ListenAndServe(envPublicAddr, muxPublic)
		}()
	}

	log.Fatal(<-errCh)
}

// Healthcheck
func (s *Server) handleHealth(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
	w.WriteHeader(http.StatusOK)
	_, _ = w.Write([]byte("ok"))
}