// Package web ist die HTTP-Schicht: Routing, Templates, Handler.
// Bewusst html/template + htmx, kein Frontend-Build (siehe CLAUDE.md,
// Stack). Jede Submission gehört einem Account (Mandant); Auth-Cookies
// binden einen Request an einen angemeldeten Nutzer und damit an dessen
// Account — siehe middleware.go.
package web

import (
	"context"
	"embed"
	"fmt"
	"html/template"
	"net/http"
	"time"

	"github.com/netcell-it/deklarix/internal/evidence"
	"github.com/netcell-it/deklarix/internal/extract"
	"github.com/netcell-it/deklarix/internal/rules"
	"github.com/netcell-it/deklarix/internal/socialconnect"
	"github.com/netcell-it/deklarix/internal/store"
)

//go:embed templates/*.html
var templatesFS embed.FS

//go:embed static/*
var staticFS embed.FS

// Extractor ist die Schnittstelle, die der Server für Stufe 1 braucht.
// *extract.Engine erfüllt sie (regelbasiert, kein externer Dienst);
// Tests injizieren einen Fake, um Facts unabhängig von der echten
// Erkennungslogik vorzugeben.
type Extractor interface {
	Extract(ctx context.Context, in extract.Input) (extract.Result, error)
	ModelVersion() string
}

// Store ist die Schnittstelle, die der Server zur Persistenz braucht —
// bewusst schmal (nur was diese Handler tatsächlich nutzen), nicht der
// komplette *store.Store. *store.Store erfüllt sie; Tests injizieren
// einen Fake statt eine echte Datenbank zu brauchen.
type Store interface {
	CreateSubmission(ctx context.Context, accountID, platform, postType, caption string) (store.Submission, error)
	GetSubmission(ctx context.Context, id string) (store.Submission, error)
	SetSubmissionStatus(ctx context.Context, id, status string) error
	CreateExtraction(ctx context.Context, submissionID string, payload []byte, modelVersion, promptVersion string) (store.Extraction, error)
	GetLatestExtraction(ctx context.Context, submissionID string) (store.Extraction, error)
	CreateFinding(ctx context.Context, submissionID string, extractionID *string, ruleID string, ruleVersion int, severity, title, fix string, sources []string) (store.Finding, error)
	ListCurrentFindings(ctx context.Context, submissionID string) ([]store.Finding, error)
	CreateEvidencePackage(ctx context.Context, submissionID, dossierPath, sha256Hex string, timestampToken []byte) (store.EvidencePackage, error)
	GetLatestEvidencePackage(ctx context.Context, submissionID string) (store.EvidencePackage, error)
	ListSubmissionsForAccount(ctx context.Context, accountID string) ([]store.SubmissionSummary, error)

	CreateParticipant(ctx context.Context, submissionID, role, name string, vorgegeben, freigegeben bool) (store.Participant, error)
	ListParticipants(ctx context.Context, submissionID string) ([]store.Participant, error)
	GetParticipant(ctx context.Context, id string) (store.Participant, error)
	UpdateParticipant(ctx context.Context, id string, vorgegeben, freigegeben bool) (store.Participant, error)
	DeleteParticipant(ctx context.Context, id string) error

	CreateAccount(ctx context.Context, name string) (store.Account, error)
	GetAccount(ctx context.Context, id string) (store.Account, error)
	ListAccounts(ctx context.Context) ([]store.Account, error)
	ListVerifiedKanzleien(ctx context.Context) ([]store.Account, error)
	SetAccountVerified(ctx context.Context, id string, verified bool) (store.Account, error)
	CreateUser(ctx context.Context, accountID, email, passwordHash, role string) (store.User, error)
	GetUserByEmail(ctx context.Context, email string) (store.User, error)
	GetUser(ctx context.Context, id string) (store.User, error)
	ListUsersForAccount(ctx context.Context, accountID string) ([]store.User, error)
	CreateSession(ctx context.Context, token, userID string, expiresAt time.Time) (store.Session, error)
	GetSession(ctx context.Context, token string) (store.Session, error)
	DeleteSession(ctx context.Context, token string) error
	CreateAuditEntry(ctx context.Context, actorUserID, action, targetType, targetID, details string) (store.AuditEntry, error)
	ListAuditLog(ctx context.Context, limit int) ([]store.AuditEntry, error)
	CreateAsset(ctx context.Context, submissionID, kind, purpose, path, sha256Hex string) (store.Asset, error)
	GetLatestAssetForSubmission(ctx context.Context, submissionID string) (store.Asset, error)
	ListAssetsForSubmission(ctx context.Context, submissionID string) ([]store.Asset, error)

	UpsertPlatformConnection(ctx context.Context, accountID, platform, platformUserID, accessToken, refreshToken string, expiresAt *time.Time) (store.PlatformConnection, error)
	ListPlatformConnectionsForAccount(ctx context.Context, accountID string) ([]store.PlatformConnection, error)
	DeletePlatformConnection(ctx context.Context, accountID, platform string) error
}

// Server bündelt Routing und Abhängigkeiten der Web-Schicht.
type Server struct {
	mux         *http.ServeMux
	extractor   Extractor
	ruleSet     []rules.Rule
	store       Store
	timestamper evidence.Timestamper
	dossierDir  string
	assetDir    string
	connectors  map[string]socialconnect.Connector
	templates   *template.Template
}

// NewServer erstellt den Server. ruleSet kommt von rules.Load und wird
// einmal beim Start geladen, nicht pro Request. dossierDir ist das
// Verzeichnis, in das erzeugte Nachweis-Dossiers geschrieben werden;
// assetDir das Verzeichnis für hochgeladene Standbilder. connectors
// enthält nur die Plattformen, für die echte Client-Credentials
// konfiguriert sind (siehe cmd/deklarix/main.go) — eine leere oder nil
// Map ist gültig, dann zeigt /verbindungen "nicht konfiguriert" statt
// eines Verbinden-Buttons.
func NewServer(extractor Extractor, ruleSet []rules.Rule, st Store, timestamper evidence.Timestamper, dossierDir, assetDir string, connectors map[string]socialconnect.Connector) (*Server, error) {
	tmpl, err := template.ParseFS(templatesFS, "templates/*.html")
	if err != nil {
		return nil, fmt.Errorf("web: templates parsen: %w", err)
	}

	s := &Server{
		extractor:   extractor,
		ruleSet:     ruleSet,
		store:       st,
		timestamper: timestamper,
		dossierDir:  dossierDir,
		assetDir:    assetDir,
		connectors:  connectors,
		templates:   tmpl,
	}

	mux := http.NewServeMux()
	mux.HandleFunc("GET /health", s.handleHealth)
	mux.HandleFunc("GET /register", s.handleRegisterForm)
	mux.HandleFunc("POST /register", s.handleRegister)
	mux.HandleFunc("GET /login", s.handleLoginForm)
	mux.HandleFunc("POST /login", s.handleLogin)
	mux.HandleFunc("POST /logout", s.handleLogout)
	mux.HandleFunc("GET /{$}", s.requirePage(s.handleIndex))
	mux.HandleFunc("POST /pruefen", s.requireAPI(s.handleCheck))
	mux.HandleFunc("POST /veroeffentlichen", s.requireAPI(s.handleArchive))
	mux.HandleFunc("GET /dossier/{id}", s.requireAPI(s.handleDossierDownload))
	mux.HandleFunc("GET /beitraege", s.requirePage(s.handleSubmissionList))
	mux.HandleFunc("GET /beitraege/{id}", s.requirePage(s.handleSubmissionDetail))
	mux.HandleFunc("POST /beitraege/{id}/beteiligte", s.requireAPI(s.handleAddParticipant))
	mux.HandleFunc("POST /beitraege/{id}/beteiligte/{pid}/aktualisieren", s.requireAPI(s.handleUpdateParticipant))
	mux.HandleFunc("POST /beitraege/{id}/beteiligte/{pid}/loeschen", s.requireAPI(s.handleDeleteParticipant))
	mux.HandleFunc("POST /beitraege/{id}/insights", s.requireAPI(s.handleAddInsightsAsset))
	mux.HandleFunc("GET /kanzleien", s.handlePublicKanzleiList)
	mux.HandleFunc("GET /verbindungen", s.requirePage(s.handleConnectionsList))
	mux.HandleFunc("GET /oauth/{platform}/start", s.requirePage(s.handleOAuthStart))
	mux.HandleFunc("GET /oauth/{platform}/callback", s.requirePage(s.handleOAuthCallback))
	mux.HandleFunc("POST /verbindungen/{platform}/trennen", s.requireAPI(s.handleDisconnect))
	mux.HandleFunc("GET /admin", s.requireAdmin(s.handleAdminDashboard))
	mux.HandleFunc("GET /admin/accounts", s.requireAdmin(s.handleAdminAccountList))
	mux.HandleFunc("GET /admin/accounts/{id}", s.requireAdmin(s.handleAdminAccountDetail))
	mux.HandleFunc("POST /admin/accounts/{id}/verifizieren", s.requireAdmin(s.handleAdminSetVerified))
	mux.HandleFunc("GET /admin/audit-log", s.requireAdmin(s.handleAdminAuditLog))
	mux.Handle("GET /static/", http.FileServerFS(staticFS))
	s.mux = mux

	return s, nil
}

// ServeHTTP macht Server zu einem http.Handler.
func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	s.mux.ServeHTTP(w, r)
}