no shebang

.gitignore

@@ -2,3 +2,5 @@
 server.log
 mem.go
 nxcaldav
+in/
+out/

.ignore

@@ -1,4 +1,6 @@
 .direnv
-server.log
+# server.log
 mem.go
 nxcaldav
+in/
+out/

README.md

@@ -21,7 +21,7 @@ DELETE FROM users WHERE name = 'bob';
 ```sql
 DELETE FROM calendars WHERE name = 'bob_calendar' AND owner_id = (SELECT id FROM users WHERE name = 'bob');
 /* or */
-DELETE FROM calendars WHERE ;
+DELETE FROM calendars WHERE path = '/bob/calendars/old/';
 ```
 ## rename calendar
 ```sql
@@ -33,3 +33,56 @@ UPDATE calendar_objects SET path = regexp_replace(path, '/old/', '/new/')' WHERE
 ```sql
 select id, path, linecut from calendar_objects, LATERAL regexp_split_to_table(data, E'\r\n') AS linecut where linecut ~ 'CLASS';
 ```
+
+
+---
+
+# Helpers
+
+## Prerequisites
+The scripts require psycopg2 (or psycopg2-binary) and PyYAML.
+
+```shell
+pip install psycopg2-binary pyyaml
+```
+
+## Exporting Events
+The `export_events.py` script extracts events from the database and saves them as `.ics` files in a structured directory format: `username/calendarID/filename.ics`.
+
+### Examples:
+- Export everything:
+```shell
+python export_events.py --output ./my_backup
+```
+
+- Export only one user:
+```shell
+python export_events.py --user alice --output ./alice_backup
+```
+
+- Export a specific calendar:
+```shell
+python export_events.py --user alice --calendar preservation --output ./preservation_backup
+```
+
+
+## Importing Events
+The `import_events.py` script uploads events back into the database. It can either walk a structured directory (like the one created by the export script) or upload a flat directory of files to a specific target calendar.
+
+### Examples:
+- Restore everything from a backup:
+```shell
+python import_events.py --input ./my_backup
+```
+
+- Upload a directory of .ics files to a specific calendar:
+```shell
+python import_events.py --input ./some_events/ --user alice --calendar work
+```
+
+- Upload a single file to a specific calendar:
+```shell
+python import_events.py --input ./event.ics --user bob --calendar bob
+```
+
+

config.yaml

@@ -1,42 +1,76 @@
-server:
-  bind_address: "0.0.0.0:14243"
-  public_url: "http://localhost:8080"
-  redaction_text: "[-]"
-  default_class: "CONFIDENTIAL"
-
 database:
-  url: "postgres://nxcaldav@localhost:5432/nxcaldav?sslmode=disable"
+  url: postgres://nxcaldav@localhost:5432/nxcaldav?sslmode=disable
+server:
+  bind_address: 0.0.0.0:14243
+  default_class: CONFIDENTIAL
+  public_url: http://nxc.nx2.site/
+  email_domain: nx2.site
+  redaction_text: '[-]'
+
+smtp:
+  host: localhost
+  port: 587
+  user: nxcaldav@nx2.site
+  password: Vastly-Wrinkle9-Corsage
 
 users:
-  - name: "daniel"
-    password: "Cyclist-Hypnotize7-Blurb"
+  - name: daniel
+    password: ll
     groups:
       - family
-  - name: "diane"
-    password: "Carve-Unluckily-Reprint1"
+  - name: lennart
+    password: ll
     groups:
       - family
-  - name: "lennart"
-    password: "Baton6-Extortion-Monologue"
-    groups:
-      - family
-  - name: "shared"
-    password: "Oxidant-Ageless3-Dispersed"
+  - name: shared
+    password: Oxidant-Ageless3-Dispersed
 
 calendars:
-  - id: "default"
-    owner: "lennart"
-  - id: "family"
-    owner: "shared"
+  - id: preservation
+    owner: lennart
+    color: '#F6F5F4'
+  - id: effort
+    owner: lennart
+    color: '#FF0000'
+  - id: experience
+    owner: lennart
+    color: '#2C33FF'
+  - id: leisure
+    owner: lennart
+    color: '#10B400'
+  - id: daniel
+    owner: daniel
+    color: '#ff2222'
+  - access:
+    - group: family
+      mode: read-write
+    id: family
+    owner: shared
+    color: '#999999'
+
+address_books:
+  - id: contacts
+    owner: lennart
+  - id: contacts
+    owner: daniel
+  - id: family
+    owner: shared
     access:
-      - groups: "family"
-        mode: "read-write"
+      - group: family
+        mode: read-write
 
 aggregates:
-  - id: "lennart_aggregate"
-    owner: "shared"
-    sources: [ "default", "family" ]
-    access:
-      - group: "diane"
-        mode: "read-only"
-      - ics: "future-only"
+- access:
+  - group: family
+    mode: read-only
+  - ics: future-only
+  id: lennart-aggregat
+  owner: lennart
+  color: '#dd9999'
+  sources:
+    - preservation
+    - effort
+    - experience
+    - leisure
+    - family
+

export_events.py

@@ -0,0 +1,76 @@
+import os
+import argparse
+import psycopg2
+import yaml
+from urllib.parse import urlparse
+
+def get_db_url(config_path):
+    with open(config_path, 'r') as f:
+        cfg = yaml.safe_load(f)
+    return cfg.get('database', {}).get('url')
+
+def export_events():
+    parser = argparse.ArgumentParser(description='Export CalDAV events from database to files.')
+    parser.add_argument('--config', default='config.yaml', help='Path to config.yaml')
+    parser.add_argument('--output', default='export', help='Output directory')
+    parser.add_argument('--user', help='Filter by user name')
+    parser.add_argument('--calendar', help='Filter by calendar ID (name in DB)')
+    
+    args = parser.parse_args()
+    
+    db_url = get_db_url(args.config)
+    if not db_url:
+        print("Error: Could not find database URL in config.")
+        return
+
+    try:
+        conn = psycopg2.connect(db_url)
+        cur = conn.cursor()
+    except Exception as e:
+        print(f"Error connecting to database: {e}")
+        return
+
+    query = """
+        SELECT u.name as user_name, c.name as cal_name, co.path, co.data
+        FROM calendar_objects co
+        JOIN calendars c ON co.calendar_id = c.id
+        JOIN users u ON c.owner_id = u.id
+        WHERE 1=1
+    """
+    params = []
+    if args.user:
+        query += " AND u.name = %s"
+        params.append(args.user)
+    if args.calendar:
+        query += " AND c.name = %s"
+        params.append(args.calendar)
+
+    cur.execute(query, params)
+    rows = cur.fetchall()
+
+    if not rows:
+        print("No events found matching the filters.")
+        return
+
+    for user_name, cal_name, obj_path, data in rows:
+        # Create directory structure: output/user/calendar/
+        target_dir = os.path.join(args.output, user_name, cal_name)
+        os.makedirs(target_dir, exist_ok=True)
+        
+        # Filename from the path (the last part after /)
+        filename = os.path.basename(obj_path)
+        if not filename: # Should not happen with valid paths
+            continue
+            
+        file_path = os.path.join(target_dir, filename)
+        with open(file_path, 'w') as f:
+            f.write(data)
+        
+        print(f"Exported: {user_name}/{cal_name}/{filename}")
+
+    cur.close()
+    conn.close()
+    print(f"Done. Exported {len(rows)} events to '{args.output}'.")
+
+if __name__ == "__main__":
+    export_events()

go.mod

@@ -10,6 +10,7 @@ require (
 )
 
 require (
+	github.com/emersion/go-vcard v0.0.0-20241024213814-c9703dde27ff // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
 	github.com/jackc/puddle/v2 v2.2.2 // indirect

go.sum

@@ -6,6 +6,8 @@ github.com/emersion/go-ical v0.0.0-20240127095438-fc1c9d8fb2b6/go.mod h1:BEksegN
 github.com/emersion/go-ical v0.0.0-20250609112844-439c63cef608 h1:5XWaET4YAcppq3l1/Yh2ay5VmQjUdq6qhJuucdGbmOY=
 github.com/emersion/go-ical v0.0.0-20250609112844-439c63cef608/go.mod h1:BEksegNspIkjCQfmzWgsgbu6KdeJ/4LwUZs7DMBzjzw=
 github.com/emersion/go-vcard v0.0.0-20230815062825-8fda7d206ec9/go.mod h1:HMJKR5wlh/ziNp+sHEDV2ltblO4JD2+IdDOWtGcQBTM=
+github.com/emersion/go-vcard v0.0.0-20241024213814-c9703dde27ff h1:4N8wnS3f1hNHSmFD5zgFkWCyA4L1kCDkImPAtK7D6tg=
+github.com/emersion/go-vcard v0.0.0-20241024213814-c9703dde27ff/go.mod h1:HMJKR5wlh/ziNp+sHEDV2ltblO4JD2+IdDOWtGcQBTM=
 github.com/emersion/go-webdav v0.7.0 h1:cp6aBWXBf8Sjzguka9VJarr4XTkGc2IHxXI1Gq3TKpA=
 github.com/emersion/go-webdav v0.7.0/go.mod h1:mI8iBx3RAODwX7PJJ7qzsKAKs/vY429YfS2/9wKnDbQ=
 github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=

import_events.py

@@ -0,0 +1,123 @@
+import os
+import argparse
+import psycopg2
+import yaml
+from urllib.parse import urlparse
+
+def get_config(config_path):
+    with open(config_path, 'r') as f:
+        return yaml.safe_load(f)
+
+def count_events(data):
+    return data.count('BEGIN:VEVENT')
+
+def import_events():
+    parser = argparse.ArgumentParser(description='Import CalDAV events from files to database.')
+    parser.add_argument('--config', default='config.yaml', help='Path to config.yaml')
+    parser.add_argument('--input', default='export', help='Input directory or file')
+    parser.add_argument('--user', help='Target user (filter or override)')
+    parser.add_argument('--calendar', help='Target calendar (filter or override)')
+    
+    args = parser.parse_args()
+    
+    cfg = get_config(args.config)
+    db_url = cfg.get('database', {}).get('url')
+    if not db_url:
+        print("Error: Could not find database URL in config.")
+        return
+
+    try:
+        conn = psycopg2.connect(db_url)
+        cur = conn.cursor()
+    except Exception as e:
+        print(f"Error connecting to database: {e}")
+        return
+
+    def upload_file(file_path, user_name, cal_name):
+        cur.execute("""
+            SELECT c.id, c.path 
+            FROM calendars c 
+            JOIN users u ON c.owner_id = u.id 
+            WHERE u.name = %s AND c.name = %s
+        """, (user_name, cal_name))
+        res = cur.fetchone()
+        if not res:
+            print(f"Warning: Calendar '{cal_name}' for user '{user_name}' not found in DB. Skipping {file_path}")
+            return False
+        
+        cal_id, cal_base_path = res
+        with open(file_path, 'r') as f:
+            data = f.read()
+        
+        filename = os.path.basename(file_path)
+        obj_path = os.path.join(cal_base_path, filename)
+        etag = f'"{count_events(data)}"'
+        
+        cur.execute("""
+            INSERT INTO calendar_objects (calendar_id, path, data, etag) 
+            VALUES (%s, %s, %s, %s)
+            ON CONFLICT (calendar_id, path) DO UPDATE 
+            SET data = EXCLUDED.data, etag = EXCLUDED.etag
+        """, (cal_id, obj_path, data, etag))
+        return True
+
+    # Gather all files
+    files_to_process = []
+    if os.path.isfile(args.input):
+        files_to_process.append(args.input)
+    elif os.path.isdir(args.input):
+        for root, _, filenames in os.walk(args.input):
+            for f in filenames:
+                if f.endswith('.ics'):
+                    files_to_process.append(os.path.join(root, f))
+    else:
+        print(f"Error: Input '{args.input}' not found.")
+        return
+
+    success_count = 0
+    for f_path in files_to_process:
+        # Determine source structure
+        # If input is a dir, rel_path is relative to it. If file, it's just the filename.
+        if os.path.isdir(args.input):
+            rel_path = os.path.relpath(f_path, args.input)
+        else:
+            rel_path = os.path.basename(f_path)
+            
+        parts = rel_path.split(os.sep)
+        
+        source_user = None
+        source_cal = None
+        
+        # Structure: user/calendar/file.ics (len 3)
+        if len(parts) >= 3:
+            source_user = parts[-3]
+            source_cal = parts[-2]
+        # Structure: calendar/file.ics (len 2)
+        elif len(parts) == 2:
+            source_cal = parts[-2]
+            
+        # 1. Apply Filtering: If flag is set and we have a source value, they must match.
+        if args.user and source_user and args.user != source_user:
+            continue
+        if args.calendar and source_cal and args.calendar != source_cal:
+            continue
+            
+        # 2. Determine Target: Flag overrides source.
+        target_user = args.user or source_user
+        target_cal = args.calendar or source_cal
+        
+        if not target_user or not target_cal:
+            print(f"Skipping {f_path}: Cannot determine user/calendar. Use --user and --calendar flags.")
+            continue
+            
+        if upload_file(f_path, target_user, target_cal):
+            print(f"Imported: {target_user}/{target_cal}/{os.path.basename(f_path)}")
+            success_count += 1
+
+    conn.commit()
+    cur.close()
+    conn.close()
+    print(f"Done. Successfully imported {success_count} events.")
+
+if __name__ == "__main__":
+    import_events()

internal/backend/db.go

@@ -1,49 +1,51 @@
 package backend
 
 import (
-	"slices"
 	"bytes"
 	"context"
 	"errors"
 	"fmt"
 	"log"
 	"net/http"
+	"net/url"
 	"os/exec"
 	"path"
+	"slices"
 	"strings"
 	"time"
 
 	"github.com/emersion/go-ical"
+	"github.com/emersion/go-vcard"
 	"github.com/emersion/go-webdav"
 	"github.com/emersion/go-webdav/caldav"
+	"github.com/emersion/go-webdav/carddav"
 	"github.com/jackc/pgx/v5"
+
 	"github.com/jackc/pgx/v5/pgxpool"
 	"golang.org/x/crypto/bcrypt"
 	"nxcaldav/internal/config"
 )
 
+// for ICS access
 type publicInfo struct {
 	InternalPath string
 	Mode         string // e.g., "future-only"
 }
 
-// DBBackend implements the caldav.Backend interface using a PostgreSQL database.
-// It manages users, calendars, and their events/tasks with built-in support for
-// access control, privacy redaction, and aggregate (virtual) calendars.
+// DBBackend = caldav.Backend interface (PostgreSQL) 
 type DBBackend struct {
 	pool          *pgxpool.Pool                // Connection pool to PostgreSQL
 	prefix        string                       // Public URL base path prefix
+	publicURL     string                       // Full public URL base (e.g. http://dav.example.com/)
 	redactionText string                       // Text used to hide confidential event details (e.g. "[REDACED]")
 	defaultClass  string                       // Class assumed if non is set ("PUBLIC", "PRIVATE", "CONFIDENTIAL")
-	aggregates    map[string]*config.Aggregate // In-memory map of path -> virtual calendar definitions
-	userAggs      map[string][]string          // In-memory map of user -> list of aggregate paths they can see
-	publicAccess  map[string]publicInfo        // In-memory map of public path -> internal info
+	emailDomain   string                       // Domain for email addresses (e.g., "example.com" if email is tony@example.com)
+	smtp          config.SMTPConfig            
+	aggregates    map[string]*config.Aggregate // In-memory maps...
+	userAggs      map[string][]string
+	publicAccess  map[string]publicInfo
 }
 
-// NewDBBackend creates a new database-backed CalDAV provider.
-// It is called once during main.go startup.
-// It initializes the database connection, ensures the tables exist (Schema),
-// and synchronizes the config.yaml data into the database tables.
 func NewDBBackend(ctx context.Context, cfg *config.Config) (*DBBackend, error) {
 	pool, err := pgxpool.New(ctx, cfg.Database.URL)
 	if err != nil {
@@ -53,8 +55,11 @@ func NewDBBackend(ctx context.Context, cfg *config.Config) (*DBBackend, error) {
 	b := &DBBackend{
 		pool:          pool,
 		prefix:        cfg.Server.BasePath(),
+		publicURL:     cfg.Server.PublicURL,
 		redactionText: cfg.Server.Redaction,
 		defaultClass:  cfg.Server.DefaultClass,
+		emailDomain:   cfg.Server.EmailDomain,
+		smtp:          cfg.SMTP,
 		aggregates:    make(map[string]*config.Aggregate),
 		userAggs:      make(map[string][]string),
 		publicAccess:  make(map[string]publicInfo),
@@ -74,8 +79,7 @@ func NewDBBackend(ctx context.Context, cfg *config.Config) (*DBBackend, error) {
 }
 
 // initSchema runs the DDL queries to create the necessary tables if they don't exist.
-// We use ON DELETE CASCADE extensively so that deleting a user or calendar
-// automatically wipes all related events and access rules in the DB.
+// it uses ON DELETE CASCADE extensively
 func (b *DBBackend) initSchema(ctx context.Context) error {
 	queries := []string{
 		`CREATE TABLE IF NOT EXISTS users (
@@ -88,7 +92,8 @@ func (b *DBBackend) initSchema(ctx context.Context) error {
 			owner_id INTEGER REFERENCES users(id) ON DELETE CASCADE,
 			path TEXT UNIQUE NOT NULL,
 			name TEXT,
-			description TEXT
+			description TEXT,
+			color TEXT
 		)`,
 		`CREATE TABLE IF NOT EXISTS calendar_access (
 			calendar_id INTEGER REFERENCES calendars(id) ON DELETE CASCADE,
@@ -104,8 +109,28 @@ func (b *DBBackend) initSchema(ctx context.Context) error {
 		    etag TEXT NOT NULL,
 		    UNIQUE (calendar_id, path)
 		)`,
+		`CREATE TABLE IF NOT EXISTS addressbooks (
+		    id SERIAL PRIMARY KEY,
+		    owner_id INTEGER REFERENCES users(id) ON DELETE CASCADE,
+		    path TEXT UNIQUE NOT NULL,
+		    name TEXT,
+		    description TEXT
+		)`,
+		`CREATE TABLE IF NOT EXISTS addressbook_access (
+		    addressbook_id INTEGER REFERENCES addressbooks(id) ON DELETE CASCADE,
+		    user_id INTEGER REFERENCES users(id) ON DELETE CASCADE,
+		    mode TEXT NOT NULL,
+		    PRIMARY KEY (addressbook_id, user_id)
+		)`,
+		`CREATE TABLE IF NOT EXISTS addressbook_objects (
+		    id SERIAL PRIMARY KEY,
+		    addressbook_id INTEGER REFERENCES addressbooks(id) ON DELETE CASCADE,
+		    path TEXT NOT NULL,
+		    data TEXT NOT NULL,
+		    etag TEXT NOT NULL,
+		    UNIQUE (addressbook_id, path)
+		)`,
 	}
-
 	for _, q := range queries {
 		if _, err := b.pool.Exec(ctx, q); err != nil {
 			return fmt.Errorf("failed to execute schema query: %v", err)
@@ -114,14 +139,10 @@ func (b *DBBackend) initSchema(ctx context.Context) error {
 	return nil
 }
 
-// resolvePassword prepares a password for storage.
-// It is called by syncConfig for every user.
-// 1. If PasswordCmd is set, it runs the bash command to get the password.
-// 2. If the password is not already a bcrypt hash, it hashes it.
 func (b *DBBackend) resolvePassword(u config.User) (string, error) {
 	var raw string
 	if u.PasswordCmd != "" {
-		cmd := exec.Command("bash", "-c", u.PasswordCmd)
+		cmd := exec.Command("sh", "-c", u.PasswordCmd)
 		out, err := cmd.Output()
 		if err != nil {
 			return "", fmt.Errorf("failed to run password command for %s: %v", u.Name, err)
@@ -144,12 +165,6 @@ func (b *DBBackend) resolvePassword(u config.User) (string, error) {
 	return string(hash), nil
 }
 
-// syncConfig reconciles the YAML configuration with the PostgreSQL state.
-// It is called once at server startup.
-// 1. Inserts/Updates all users and their hashed passwords.
-// 2. Inserts/Updates all calendars and their access/group rules.
-// 3. Builds the in-memory Aggregate maps for fast lookup during requests.
-// 4. Performs an 'Orphan Check' to warn the user about DB entries not in config.
 func (b *DBBackend) syncConfig(ctx context.Context, cfg *config.Config) error {
 	tx, err := b.pool.Begin(ctx)
 	if err != nil {
@@ -168,6 +183,7 @@ func (b *DBBackend) syncConfig(ctx context.Context, cfg *config.Config) error {
 	prefix := cfg.Server.BasePath()
 
 	// --- Phase 1: User Sync ---
+	// Inserts/Updates all users and their hashed passwords.
 	for _, u := range cfg.Users {
 		configUserNames[u.Name] = true
 		for _, g := range u.Groups {
@@ -188,6 +204,7 @@ func (b *DBBackend) syncConfig(ctx context.Context, cfg *config.Config) error {
 	}
 
 	// --- Phase 2: Calendar & Access Sync ---
+	// Inserts/Updates all calendars and their access/group rules.
 	for _, c := range cfg.Calendars {
 		path := prefix + fmt.Sprintf("/%s/calendars/%s/", c.Owner, c.ID)
 		configCalendarPaths[path] = true
@@ -200,10 +217,10 @@ func (b *DBBackend) syncConfig(ctx context.Context, cfg *config.Config) error {
 
 		var calID int
 		err = tx.QueryRow(ctx, `
-			INSERT INTO calendars (owner_id, path, name) VALUES ($1, $2, $3)
-			ON CONFLICT (path) DO UPDATE SET owner_id = EXCLUDED.owner_id, name = EXCLUDED.name
+			INSERT INTO calendars (owner_id, path, name, color) VALUES ($1, $2, $3, $4)
+			ON CONFLICT (path) DO UPDATE SET owner_id = EXCLUDED.owner_id, name = EXCLUDED.name, color = EXCLUDED.color
 			RETURNING id`,
-			ownerID, path, c.ID).Scan(&calID)
+			ownerID, path, c.ID, c.Color).Scan(&calID)
 		if err != nil {
 			return err
 		}
@@ -256,6 +273,65 @@ func (b *DBBackend) syncConfig(ctx context.Context, cfg *config.Config) error {
 		}
 	}
 
+	// --- Phase 2.5: Address Book & Access Sync ---
+	configAddressBookPaths := make(map[string]bool)
+	for _, ab := range cfg.AddressBooks {
+		path := prefix + fmt.Sprintf("/%s/addressbooks/%s/", ab.Owner, ab.ID)
+		configAddressBookPaths[path] = true
+
+		var ownerID int
+		err := tx.QueryRow(ctx, "SELECT id FROM users WHERE name = $1", ab.Owner).Scan(&ownerID)
+		if err != nil {
+			return fmt.Errorf("owner %s not found: %v", ab.Owner, err)
+		}
+
+		var abID int
+		err = tx.QueryRow(ctx, `
+			INSERT INTO addressbooks (owner_id, path, name) VALUES ($1, $2, $3)
+			ON CONFLICT (path) DO UPDATE SET owner_id = EXCLUDED.owner_id, name = EXCLUDED.name
+			RETURNING id`,
+			ownerID, path, ab.ID).Scan(&abID)
+		if err != nil {
+			return err
+		}
+
+		// Re-build access rules for this address book
+		_, err = tx.Exec(ctx, "DELETE FROM addressbook_access WHERE addressbook_id = $1", abID)
+		if err != nil {
+			return err
+		}
+
+		addressBookAccessModes := make(map[string]string)
+		for _, a := range ab.Access {
+			var tUsers []string
+			if a.User != "" {
+				tUsers = append(tUsers, a.User)
+			}
+			if a.Group != "" {
+				tUsers = append(tUsers, groupMembers[a.Group]...)
+			}
+			if a.Groups != "" {
+				tUsers = append(tUsers, groupMembers[a.Groups]...)
+			}
+			for _, u := range tUsers {
+				addressBookAccessModes[u] = a.Mode
+			}
+		}
+
+		for uName, mode := range addressBookAccessModes {
+			var userID int
+			err := tx.QueryRow(ctx, "SELECT id FROM users WHERE name = $1", uName).Scan(&userID)
+			if err != nil {
+				return fmt.Errorf("access user %s not found: %v", uName, err)
+			}
+			_, err = tx.Exec(ctx, "INSERT INTO addressbook_access (addressbook_id, user_id, mode) VALUES ($1, $2, $3)",
+				abID, userID, mode)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
 	// --- Phase 3: Aggregate Setup ---
 	// Aggregates are virtual, so we only track them in memory for routing.
 	for _, agg := range cfg.Aggregates {
@@ -319,7 +395,6 @@ func (b *DBBackend) syncConfig(ctx context.Context, cfg *config.Config) error {
 		}
 		calRows.Close()
 	}
-	
 	return tx.Commit(ctx)
 }
 
@@ -358,13 +433,12 @@ func (b *DBBackend) getUsername(ctx context.Context) (string, error) {
 
 // --- Internal Security & Privacy Helpers ---
 
-// checkAccess verifies if the current user has the required permission for a real calendar.
-// It returns the internal database ID of the calendar if access is granted.
-// It is called before any read (PROPFIND, GET, REPORT) or write (PUT, DELETE) operation.
-func (b *DBBackend) checkAccess(ctx context.Context, calendarPath string, requiredMode string) (int, error) {
+// for a real calendars
+// returns internal database ID if granted
+func (b *DBBackend) checkAccess(ctx context.Context, calendarPath string, requiredMode string) (int, string, error) {
 	username, err := b.getUsername(ctx)
 	if err != nil {
-		return 0, err
+		return 0, "", err
 	}
 
 	if !strings.HasSuffix(calendarPath, "/") {
@@ -380,14 +454,14 @@ func (b *DBBackend) checkAccess(ctx context.Context, calendarPath string, requir
 		WHERE c.path = $1`, calendarPath).Scan(&calID, &ownerName)
 	if err != nil {
 		if errors.Is(err, pgx.ErrNoRows) {
-			return 0, webdav.NewHTTPError(http.StatusNotFound, errors.New("calendar not found"))
+			return 0, "", webdav.NewHTTPError(http.StatusNotFound, errors.New("calendar not found"))
 		}
-		return 0, err
+		return 0, "", err
 	}
 
 	// Owners always have full access
 	if ownerName == username {
-		return calID, nil
+		return calID, "owner", nil
 	}
 
 	// Check the calendar_access table for specific permissions
@@ -398,34 +472,29 @@ func (b *DBBackend) checkAccess(ctx context.Context, calendarPath string, requir
 		calID, username).Scan(&mode)
 	if err != nil {
 		if errors.Is(err, pgx.ErrNoRows) {
-			return 0, webdav.NewHTTPError(http.StatusForbidden, errors.New("access denied"))
+			return 0, "", webdav.NewHTTPError(http.StatusForbidden, errors.New("access denied"))
 		}
-		return 0, err
+		return 0, "", err
 	}
 
 	// Enforce Read-Only mode
 	if requiredMode == "write" && mode != "read-write" {
-		return 0, webdav.NewHTTPError(http.StatusForbidden, errors.New("read-only access"))
+		return 0, "", webdav.NewHTTPError(http.StatusForbidden, errors.New("read-only access"))
 	}
 
-	return calID, nil
+	return calID, mode, nil
 }
 
-// filterCalendar is the privacy enforcement engine of the server.
-// It is called every time a calendar object is retrieved from the database
-// for a user who is NOT the owner.
-// It applies the following rules based on the 'CLASS' property of an event/task:
-// 1. PRIVATE: Removes the object entirely.
-// 2. CONFIDENTIAL: Redacts the summary to the configured 'redactionText' while keeping time data.
-// 3. PUBLIC: Passes the object through unchanged.
-func (b *DBBackend) filterCalendar(ctx context.Context, ownerName string, original *ical.Calendar) (*ical.Calendar, error) {
+// Privacy engine
+func (b *DBBackend) filterCalendar(ctx context.Context, ownerName string, mode string, original *ical.Calendar) (*ical.Calendar, error) {
 	username, err := b.getUsername(ctx)
 	if err != nil {
 		return nil, err
 	}
 
-	// Owners see everything unredacted
-	if username == ownerName {
+	// Owners and users with read-write access see everything unredacted.
+	// We check both username and mode for robustness.
+	if username == ownerName || mode == "owner" || mode == "read-write" {
 		return original, nil
 	}
 
@@ -438,7 +507,7 @@ func (b *DBBackend) filterCalendar(ctx context.Context, ownerName string, origin
 			continue
 		}
 
-		class := b.defaultClass;
+		class := b.defaultClass
 		if prop := child.Props.Get("CLASS"); prop != nil {
 			class = strings.ToUpper(prop.Value)
 		}
@@ -499,7 +568,7 @@ func (b *DBBackend) ServePublicICS(w http.ResponseWriter, r *http.Request) {
 			JOIN users u ON c.owner_id = u.id 
 			WHERE c.path = $1`, info.InternalPath).Scan(&calID, &ownerName)
 		if err == nil {
-			objects, err = b.listCalendarObjectsRaw(ctx, calID, ownerName)
+			objects, err = b.listCalendarObjectsRaw(ctx, calID, ownerName, "read")
 		}
 	}
 
@@ -639,7 +708,7 @@ func (b *DBBackend) ListCalendarObjects(ctx context.Context, p string, req *cald
 	}
 
 	username, _ := b.getUsername(ctx)
-	log.Printf("[ListCalendarObjects] user=%s path=%s", username, p)
+	log.Printf("[user: %s] ListCalendarObjects %s", username, p)
 
 	// Route to virtual aggregate logic if needed
 	if agg, ok := b.aggregates[p]; ok {
@@ -652,7 +721,7 @@ func (b *DBBackend) ListCalendarObjects(ctx context.Context, p string, req *cald
 	}
 
 	// Normal calendar logic
-	calID, err := b.checkAccess(ctx, p, "read")
+	calID, mode, err := b.checkAccess(ctx, p, "read")
 	if err != nil {
 		return nil, err
 	}
@@ -663,10 +732,10 @@ func (b *DBBackend) ListCalendarObjects(ctx context.Context, p string, req *cald
 		return nil, err
 	}
 
-	return b.listCalendarObjectsRaw(ctx, calID, ownerName)
+	return b.listCalendarObjectsRaw(ctx, calID, ownerName, mode)
 }
 
-func (b *DBBackend) listCalendarObjectsRaw(ctx context.Context, calID int, ownerName string) ([]caldav.CalendarObject, error) {
+func (b *DBBackend) listCalendarObjectsRaw(ctx context.Context, calID int, ownerName string, mode string) ([]caldav.CalendarObject, error) {
 	rows, err := b.pool.Query(ctx, "SELECT path, data, etag FROM calendar_objects WHERE calendar_id = $1", calID)
 	if err != nil {
 		return nil, err
@@ -687,7 +756,7 @@ func (b *DBBackend) listCalendarObjectsRaw(ctx context.Context, calID int, owner
 		}
 
 		// Apply privacy filters (Private/Confidential)
-		filteredData, err := b.filterCalendar(ctx, ownerName, calData)
+		filteredData, err := b.filterCalendar(ctx, ownerName, mode, calData)
 		if err != nil || filteredData == nil {
 			continue
 		}
@@ -701,6 +770,7 @@ func (b *DBBackend) listCalendarObjectsRaw(ctx context.Context, calID int, owner
 // It rewrites paths so the client thinks items are in the virtual directory.
 func (b *DBBackend) listAggregateObjects(ctx context.Context, aggPath string, agg *config.Aggregate) ([]caldav.CalendarObject, error) {
 	var res []caldav.CalendarObject
+	username, _ := b.getUsername(ctx)
 
 	for _, sourceID := range agg.Sources {
 		sourcePath := b.prefix + fmt.Sprintf("/%s/calendars/%s/", agg.Owner, sourceID)
@@ -715,7 +785,21 @@ func (b *DBBackend) listAggregateObjects(ctx context.Context, aggPath string, ag
 			continue
 		}
 
-		objs, err := b.listCalendarObjectsRaw(ctx, calID, ownerName)
+		// Determine access mode for this user on this source calendar
+		mode := "read"
+		if username == ownerName {
+			mode = "owner"
+		} else if username != "" {
+			err = b.pool.QueryRow(ctx, `
+				SELECT mode FROM calendar_access 
+				WHERE calendar_id = $1 AND user_id = (SELECT id FROM users WHERE name = $2)`,
+				calID, username).Scan(&mode)
+			if err != nil {
+				mode = "read" // Assume read-only if no explicit entry
+			}
+		}
+
+		objs, err := b.listCalendarObjectsRaw(ctx, calID, ownerName, mode)
 		if err != nil {
 			continue
 		}
@@ -746,7 +830,7 @@ func (b *DBBackend) listAggregateObjects(ctx context.Context, aggPath string, ag
 // Called during GET, multiget REPORT, or when clicking an event in the client.
 func (b *DBBackend) GetCalendarObject(ctx context.Context, p string, req *caldav.CalendarCompRequest) (*caldav.CalendarObject, error) {
 	username, _ := b.getUsername(ctx)
-	log.Printf("[GetCalendarObject] user=%s path=%s", username, p)
+	log.Printf("[user: %s] GetCalendarObject %s", username, p)
 
 	dirPath := path.Dir(p) + "/"
 	fileName := path.Base(p)
@@ -788,7 +872,21 @@ func (b *DBBackend) GetCalendarObject(ctx context.Context, p string, req *caldav
 			return nil, err
 		}
 
-		filteredData, err := b.filterCalendar(ctx, ownerName, calData)
+		// Determine access mode for this user on this source calendar
+		mode := "read"
+		if username == ownerName {
+			mode = "owner"
+		} else if username != "" {
+			err = b.pool.QueryRow(ctx, `
+				SELECT mode FROM calendar_access 
+				WHERE calendar_id = $1 AND user_id = (SELECT id FROM users WHERE name = $2)`,
+				calID, username).Scan(&mode)
+			if err != nil {
+				mode = "read" // Assume read-only if no explicit entry
+			}
+		}
+
+		filteredData, err := b.filterCalendar(ctx, ownerName, mode, calData)
 		if err != nil || filteredData == nil {
 			return nil, webdav.NewHTTPError(http.StatusNotFound, errors.New("item filtered out"))
 		}
@@ -814,7 +912,7 @@ func (b *DBBackend) GetCalendarObject(ctx context.Context, p string, req *caldav
 		dirPath += "/"
 	}
 
-	calID, err := b.checkAccess(ctx, dirPath, "read")
+	calID, mode, err := b.checkAccess(ctx, dirPath, "read")
 	if err != nil {
 		return nil, err
 	}
@@ -841,7 +939,7 @@ func (b *DBBackend) GetCalendarObject(ctx context.Context, p string, req *caldav
 	}
 
 	// Apply privacy filtering
-	filteredData, err := b.filterCalendar(ctx, ownerName, calData)
+	filteredData, err := b.filterCalendar(ctx, ownerName, mode, calData)
 	if err != nil || filteredData == nil {
 		return nil, webdav.NewHTTPError(http.StatusNotFound, errors.New("calendar object not found"))
 	}
@@ -859,7 +957,7 @@ func (b *DBBackend) PutCalendarObject(ctx context.Context, p string, calendar *i
 		return nil, webdav.NewHTTPError(http.StatusForbidden, errors.New("aggregates are read-only"))
 	}
 
-	calID, err := b.checkAccess(ctx, dirPath, "write")
+	calID, _, err := b.checkAccess(ctx, dirPath, "write")
 	if err != nil {
 		return nil, err
 	}
@@ -880,6 +978,88 @@ func (b *DBBackend) PutCalendarObject(ctx context.Context, p string, calendar *i
 		return nil, err
 	}
 
+	// Step 3: Handle Status Propagation & Invitations
+	username, _ := b.getUsername(ctx)
+	userEmail := strings.ToLower(username + "@" + b.emailDomain)
+
+	for _, event := range calendar.Events() {
+		organizer := event.Props.Get("ORGANIZER")
+		orgEmail := ""
+		if organizer != nil {
+			orgEmail = strings.TrimPrefix(strings.ToLower(organizer.Value), "mailto:")
+		}
+
+		// --- Case A: User is the ATTENDEE updating their status ---
+		// If the user is NOT the organizer, but is an attendee, find the organizer's
+		// original event and update the status there.
+		if orgEmail != "" && orgEmail != userEmail {
+			log.Printf("[scheduling] Attendee %s updated event. Propagating to organizer %s", userEmail, orgEmail)
+
+			// Find the attendee's status in this version
+			myStatus := "NEEDS-ACTION"
+			for _, att := range event.Props["ATTENDEE"] {
+				if strings.TrimPrefix(strings.ToLower(att.Value), "mailto:") == userEmail {
+					if stat := att.Params.Get("PARTSTAT"); stat != "" {
+						myStatus = stat
+					}
+					break
+				}
+			}
+
+			// Find the UID of this event to locate the organizer's copy
+			uid := ""
+			if u := event.Props.Get("UID"); u != nil {
+				uid = u.Value
+			}
+
+			if uid != "" {
+				// Search for the organizer's copy in their calendars
+				go b.propagateStatusToOrganizer(orgEmail, userEmail, uid, myStatus)
+			}
+			continue // Don't send invitations from an attendee's PUT
+		}
+
+		// --- Case B: User is the ORGANIZER (Sending Invitations) ---
+		// Only send invites if the user is the organizer and we are in the owner's calendar
+		isOwnerCalendar := strings.Contains(p, "/"+username+"/")
+		if !isOwnerCalendar || (orgEmail != "" && orgEmail != userEmail) {
+			continue
+		}
+
+		attendees := event.Props["ATTENDEE"]
+		if len(attendees) == 0 {
+			continue
+		}
+
+		summary := ""
+		if s := event.Props.Get("SUMMARY"); s != nil {
+			summary = s.Value
+		}
+		description := ""
+		if d := event.Props.Get("DESCRIPTION"); d != nil {
+			description = d.Value
+		}
+		start := ""
+		if dtstart, err := event.DateTimeStart(time.UTC); err == nil {
+			start = dtstart.Format(time.RFC1123)
+		}
+		end := ""
+		if dtend, err := event.DateTimeEnd(time.UTC); err == nil {
+			end = dtend.Format(time.RFC1123)
+		}
+
+		for _, attendee := range attendees {
+			recipientEmail := strings.TrimPrefix(attendee.Value, "mailto:")
+			if recipientEmail == "" {
+				continue
+			}
+			// Only send if it's a valid looking email and not the sender themselves
+			if strings.Contains(recipientEmail, "@") && !strings.HasPrefix(recipientEmail, username+"@") {
+				go b.sendInvitation(username, recipientEmail, summary, description, start, end, p, dataStr)
+			}
+		}
+	}
+
 	return &caldav.CalendarObject{
 		Path: p,
 		Data: calendar,
@@ -895,7 +1075,7 @@ func (b *DBBackend) DeleteCalendarObject(ctx context.Context, p string) error {
 		return webdav.NewHTTPError(http.StatusForbidden, errors.New("aggregates are read-only"))
 	}
 
-	calID, err := b.checkAccess(ctx, dirPath, "write")
+	calID, _, err := b.checkAccess(ctx, dirPath, "write")
 	if err != nil {
 		return err
 	}
@@ -910,11 +1090,386 @@ func (b *DBBackend) DeleteCalendarObject(ctx context.Context, p string) error {
 	return nil
 }
 
+// propagateStatusToOrganizer finds the original event in the organizer's calendar
+// and updates the attendee's status.
+func (b *DBBackend) propagateStatusToOrganizer(orgEmail, attendeeEmail, uid, status string) {
+	ctx := context.Background()
+	log.Printf("[scheduling] Searching for original event UID %s for organizer %s", uid, orgEmail)
+
+	// 1. Find the organizer's user ID
+	var orgUserID int
+	err := b.pool.QueryRow(ctx, "SELECT id FROM users WHERE name = $1 OR name = $2",
+		strings.Split(orgEmail, "@")[0], orgEmail).Scan(&orgUserID)
+	if err != nil {
+		log.Printf("[scheduling] Could not find organizer user %s: %v", orgEmail, err)
+		return
+	}
+
+	// 2. Find the calendar object by UID within organizer's calendars
+	rows, err := b.pool.Query(ctx, `
+		SELECT co.path, co.data, co.calendar_id 
+		FROM calendar_objects co
+		JOIN calendars c ON co.calendar_id = c.id
+		WHERE c.owner_id = $1 AND co.data LIKE '%' || $2 || '%'`,
+		orgUserID, uid)
+	if err != nil {
+		log.Printf("[scheduling] Error searching for organizer's copy: %v", err)
+		return
+	}
+	defer rows.Close()
+
+	for rows.Next() {
+		var p, dataStr string
+		var calID int
+		if err := rows.Scan(&p, &dataStr, &calID); err != nil {
+			continue
+		}
+
+		// Verify UID (LIKE is just a hint)
+		calendar, err := ical.NewDecoder(strings.NewReader(dataStr)).Decode()
+		if err != nil {
+			continue
+		}
+
+		found := false
+		for _, event := range calendar.Events() {
+			if u := event.Props.Get("UID"); u != nil && u.Value == uid {
+				// Update attendee status
+				for _, att := range event.Props["ATTENDEE"] {
+					if strings.TrimPrefix(strings.ToLower(att.Value), "mailto:") == attendeeEmail {
+						log.Printf("[scheduling] Updating %s status to %s in organizer's copy %s", attendeeEmail, status, p)
+						att.Params.Set("PARTSTAT", status)
+						found = true
+					}
+				}
+			}
+		}
+
+		if found {
+			var buf bytes.Buffer
+			if err := ical.NewEncoder(&buf).Encode(calendar); err == nil {
+				newEtag := fmt.Sprintf(`"%d-%d"`, time.Now().Unix(), buf.Len())
+				b.pool.Exec(ctx, "UPDATE calendar_objects SET data = $1, etag = $2 WHERE calendar_id = $3 AND path = $4",
+					buf.String(), newEtag, calID, p)
+				log.Printf("[scheduling] Organizer's copy %s updated successfully", p)
+			}
+		}
+	}
+}
+
+// RespondToInvitation handles an attendee's Accept/Decline response.
+func (b *DBBackend) RespondToInvitation(ctx context.Context, p, attendeeEmail, status string) error {
+	log.Printf("[email] Response for %s from %s: %s", p, attendeeEmail, status)
+
+	// 1. Fetch the calendar object
+	var dataStr string
+	var calID int
+	err := b.pool.QueryRow(ctx, "SELECT calendar_id, data FROM calendar_objects WHERE path = $1", p).Scan(&calID, &dataStr)
+	if err != nil {
+		return fmt.Errorf("failed to find calendar object: %v", err)
+	}
+
+	calendar, err := ical.NewDecoder(strings.NewReader(dataStr)).Decode()
+	if err != nil {
+		return fmt.Errorf("failed to decode calendar data: %v", err)
+	}
+
+	// 2. Update PARTSTAT for the attendee
+	modified := false
+	status = strings.ToUpper(status)
+	attendeeEmail = strings.ToLower(strings.TrimSpace(attendeeEmail))
+
+	for _, event := range calendar.Events() {
+		attendees := event.Props["ATTENDEE"]
+		for _, attendee := range attendees {
+			email := strings.TrimPrefix(strings.ToLower(attendee.Value), "mailto:")
+			if email == attendeeEmail {
+				attendee.Params.Set("PARTSTAT", status)
+				modified = true
+			}
+		}
+	}
+
+	if !modified {
+		return fmt.Errorf("attendee %s not found in event", attendeeEmail)
+	}
+
+	// 3. Save back to DB
+	var buf bytes.Buffer
+	if err := ical.NewEncoder(&buf).Encode(calendar); err != nil {
+		return err
+	}
+	newDataStr := buf.String()
+	// Use a timestamp + length for a unique ETag
+	newEtag := fmt.Sprintf(`"%d-%d"`, time.Now().Unix(), len(newDataStr))
+
+	_, err = b.pool.Exec(ctx, "UPDATE calendar_objects SET data = $1, etag = $2 WHERE calendar_id = $3 AND path = $4",
+		newDataStr, newEtag, calID, p)
+	if err != nil {
+		return fmt.Errorf("failed to update calendar object in DB: %v", err)
+	}
+
+	log.Printf("[email] Successfully updated status to %s for %s in %s", status, attendeeEmail, p)
+	return nil
+}
+
 // QueryCalendarObjects filters items based on a CalDAV query (e.g. time range).
 // Currently, it just lists all objects and lets the client filter, but
 // we use it to enforce privacy rules for the initial report.
 func (b *DBBackend) QueryCalendarObjects(ctx context.Context, path_ string, query *caldav.CalendarQuery) ([]caldav.CalendarObject, error) {
 	username, _ := b.getUsername(ctx)
-	log.Printf("[QueryCalendarObjects] user=%s path=%s", username, path_)
+	log.Printf("[user: %s] QueryCalendarObjects %s", username, path_)
 	return b.ListCalendarObjects(ctx, path_, nil)
 }
+
+func (b *DBBackend) GetColor(ctx context.Context, p string) string {
+	// If p is a full URL, extract the path
+	if strings.HasPrefix(p, "http") {
+		if u, err := url.Parse(p); err == nil {
+			p = u.Path
+		}
+	}
+
+	if !strings.HasSuffix(p, "/") {
+		p += "/"
+	}
+
+	// Check if it's an aggregate
+	if agg, ok := b.aggregates[p]; ok {
+		return agg.Color
+	}
+
+	// Check if it's a real calendar
+	var color string
+	err := b.pool.QueryRow(ctx, "SELECT color FROM calendars WHERE path = $1", p).Scan(&color)
+	if err == nil {
+		return color
+	}
+	return ""
+}
+
+// --- CardDAV ---
+
+func (b *DBBackend) AddressBookHomeSetPath(ctx context.Context) (string, error) {
+	username, err := b.getUsername(ctx)
+	if err != nil {
+		return "", err
+	}
+	return b.prefix + fmt.Sprintf("/%s/addressbooks/", username), nil
+}
+
+func (b *DBBackend) ListAddressBooks(ctx context.Context) ([]carddav.AddressBook, error) {
+	username, err := b.getUsername(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	rows, err := b.pool.Query(ctx, `
+	        SELECT path, name, COALESCE(description, '') FROM addressbooks 
+	        WHERE owner_id = (SELECT id FROM users WHERE name = $1)
+	        OR id IN (SELECT addressbook_id FROM addressbook_access WHERE user_id = (SELECT id FROM users WHERE name = $1))`,
+		username)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var res []carddav.AddressBook
+	for rows.Next() {
+		var ab carddav.AddressBook
+		if err := rows.Scan(&ab.Path, &ab.Name, &ab.Description); err != nil {
+			return nil, err
+		}
+		ab.MaxResourceSize = 1000000
+		ab.SupportedAddressData = []carddav.AddressDataType{
+			{ContentType: "text/vcard", Version: "3.0"},
+			{ContentType: "text/vcard", Version: "4.0"},
+		}
+		res = append(res, ab)
+	}
+	return res, nil
+}
+
+func (b *DBBackend) GetAddressBook(ctx context.Context, p string) (*carddav.AddressBook, error) {
+	if !strings.HasSuffix(p, "/") {
+		p += "/"
+	}
+
+	var ab carddav.AddressBook
+	err := b.pool.QueryRow(ctx, "SELECT path, name, COALESCE(description, '') FROM addressbooks WHERE path = $1", p).Scan(&ab.Path, &ab.Name, &ab.Description)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			return nil, webdav.NewHTTPError(http.StatusNotFound, errors.New("address book not found"))
+		}
+		return nil, err
+	}
+	ab.MaxResourceSize = 1000000
+	ab.SupportedAddressData = []carddav.AddressDataType{
+		{ContentType: "text/vcard", Version: "3.0"},
+		{ContentType: "text/vcard", Version: "4.0"},
+	}
+	return &ab, nil
+}
+
+func (b *DBBackend) CreateAddressBook(ctx context.Context, addressBook *carddav.AddressBook) error {
+	return webdav.NewHTTPError(http.StatusForbidden, errors.New("address book creation only via config"))
+}
+
+func (b *DBBackend) DeleteAddressBook(ctx context.Context, p string) error {
+	return webdav.NewHTTPError(http.StatusForbidden, errors.New("address book deletion only via config"))
+}
+
+func (b *DBBackend) checkAddressBookAccess(ctx context.Context, abPath string, requiredMode string) (int, string, error) {
+	username, err := b.getUsername(ctx)
+	if err != nil {
+		return 0, "", err
+	}
+
+	if !strings.HasSuffix(abPath, "/") {
+		abPath += "/"
+	}
+
+	var abID int
+	var ownerName string
+	err = b.pool.QueryRow(ctx, `
+	        SELECT a.id, u.name 
+	        FROM addressbooks a 
+	        JOIN users u ON a.owner_id = u.id 
+	        WHERE a.path = $1`, abPath).Scan(&abID, &ownerName)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			return 0, "", webdav.NewHTTPError(http.StatusNotFound, errors.New("address book not found"))
+		}
+		return 0, "", err
+	}
+
+	if ownerName == username {
+		return abID, "owner", nil
+	}
+
+	var mode string
+	err = b.pool.QueryRow(ctx, `
+	        SELECT mode FROM addressbook_access 
+	        WHERE addressbook_id = $1 AND user_id = (SELECT id FROM users WHERE name = $2)`,
+		abID, username).Scan(&mode)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			return 0, "", webdav.NewHTTPError(http.StatusForbidden, errors.New("access denied"))
+		}
+		return 0, "", err
+	}
+
+	if requiredMode == "write" && mode != "read-write" {
+		return 0, "", webdav.NewHTTPError(http.StatusForbidden, errors.New("read-only access"))
+	}
+	return abID, mode, nil
+}
+
+func (b *DBBackend) ListAddressObjects(ctx context.Context, p string, req *carddav.AddressDataRequest) ([]carddav.AddressObject, error) {
+	if !strings.HasSuffix(p, "/") {
+		p += "/"
+	}
+
+	abID, _, err := b.checkAddressBookAccess(ctx, p, "read")
+	if err != nil {
+		return nil, err
+	}
+
+	rows, err := b.pool.Query(ctx, "SELECT path, data, etag FROM addressbook_objects WHERE addressbook_id = $1", abID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var res []carddav.AddressObject
+	for rows.Next() {
+		var obj carddav.AddressObject
+		var dataStr string
+		if err := rows.Scan(&obj.Path, &dataStr, &obj.ETag); err != nil {
+			return nil, err
+		}
+
+		card, err := vcard.NewDecoder(strings.NewReader(dataStr)).Decode()
+		if err != nil {
+			continue
+		}
+		obj.Card = card
+		res = append(res, obj)
+	}
+	return res, nil
+}
+
+func (b *DBBackend) GetAddressObject(ctx context.Context, p string, req *carddav.AddressDataRequest) (*carddav.AddressObject, error) {
+	dirPath := path.Dir(p) + "/"
+	abID, _, err := b.checkAddressBookAccess(ctx, dirPath, "read")
+	if err != nil {
+		return nil, err
+	}
+
+	var obj carddav.AddressObject
+	var dataStr string
+	err = b.pool.QueryRow(ctx, "SELECT path, data, etag FROM addressbook_objects WHERE addressbook_id = $1 AND path = $2", abID, p).Scan(&obj.Path, &dataStr, &obj.ETag)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			return nil, webdav.NewHTTPError(http.StatusNotFound, errors.New("address book object not found"))
+		}
+		return nil, err
+	}
+
+	card, err := vcard.NewDecoder(strings.NewReader(dataStr)).Decode()
+	if err != nil {
+		return nil, err
+	}
+	obj.Card = card
+	return &obj, nil
+}
+
+func (b *DBBackend) PutAddressObject(ctx context.Context, p string, card vcard.Card, opts *carddav.PutAddressObjectOptions) (*carddav.AddressObject, error) {
+	dirPath := path.Dir(p) + "/"
+	abID, _, err := b.checkAddressBookAccess(ctx, dirPath, "write")
+	if err != nil {
+		return nil, err
+	}
+
+	var buf bytes.Buffer
+	if err := vcard.NewEncoder(&buf).Encode(card); err != nil {
+		return nil, err
+	}
+	dataStr := buf.String()
+	etag := fmt.Sprintf(`"%d"`, len(dataStr))
+
+	_, err = b.pool.Exec(ctx, `
+                INSERT INTO addressbook_objects (addressbook_id, path, data, etag) VALUES ($1, $2, $3, $4)
+                ON CONFLICT (addressbook_id, path) DO UPDATE SET data = EXCLUDED.data, etag = EXCLUDED.etag`,
+		abID, p, dataStr, etag)
+	if err != nil {
+		return nil, err
+	}
+
+	return &carddav.AddressObject{
+		Path: p,
+		Card: card,
+		ETag: etag,
+	}, nil
+}
+
+func (b *DBBackend) DeleteAddressObject(ctx context.Context, p string) error {
+	dirPath := path.Dir(p) + "/"
+	abID, _, err := b.checkAddressBookAccess(ctx, dirPath, "write")
+	if err != nil {
+		return err
+	}
+
+	commandTag, err := b.pool.Exec(ctx, "DELETE FROM addressbook_objects WHERE addressbook_id = $1 AND path = $2", abID, p)
+	if err != nil {
+		return err
+	}
+	if commandTag.RowsAffected() == 0 {
+		return webdav.NewHTTPError(http.StatusNotFound, errors.New("address book object not found"))
+	}
+	return nil
+}
+
+func (b *DBBackend) QueryAddressObjects(ctx context.Context, p string, query *carddav.AddressBookQuery) ([]carddav.AddressObject, error) {
+	return b.ListAddressObjects(ctx, p, nil)
+}

internal/backend/email.go

@@ -0,0 +1,119 @@
+package backend
+
+import (
+	"bytes"
+	"crypto/tls"
+	"fmt"
+	"log"
+	"net/smtp"
+	"net/url"
+	"strings"
+
+	"github.com/emersion/go-ical"
+)
+
+// sendInvitation sends an iMIP (RFC 6047) invitation email.
+// It includes a plain-text fallback and a METHOD:REQUEST iCalendar attachment
+// that calendar clients (Thunderbird, Apple, etc.) will recognize.
+func (b *DBBackend) sendInvitation(senderName, recipientEmail, summary, description, start, end, objectPath, originalICS string) error {
+	fromAddr := fmt.Sprintf("%s@%s", senderName, b.emailDomain)
+	if b.smtp.User != "" {
+		fromAddr = b.smtp.User
+	}
+	fromHeader := fmt.Sprintf("%s <%s>", senderName, fromAddr)
+	
+	baseURL := strings.TrimSuffix(b.publicURL, "/")
+	acceptURL := fmt.Sprintf("%s/respond?path=%s&attendee=%s&status=ACCEPTED", baseURL, url.QueryEscape(objectPath), url.QueryEscape(recipientEmail))
+	declineURL := fmt.Sprintf("%s/respond?path=%s&attendee=%s&status=DECLINED", baseURL, url.QueryEscape(objectPath), url.QueryEscape(recipientEmail))
+
+	// 1. Prepare plain-text fallback - with prominent links
+	textPart := "PLEASE RESPOND TO THIS INVITATION:\r\n"
+	textPart += fmt.Sprintf("✅ ACCEPT:  %s\r\n", acceptURL)
+	textPart += fmt.Sprintf("❌ DECLINE: %s\r\n", declineURL)
+	textPart += "\r\n------------------------------------------\r\n\r\n"
+	textPart += fmt.Sprintf("You have been invited to an event by %s.\r\n\r\n", senderName)
+	textPart += fmt.Sprintf("Event: %s\r\n", summary)
+
+	// 2. Prepare iCalendar part with METHOD:REQUEST
+	var icsContent string
+	calendar, err := ical.NewDecoder(strings.NewReader(originalICS)).Decode()
+	if err == nil {
+		calendar.Props.SetText("METHOD", "REQUEST")
+		// Discourage clients from sending their own response emails
+		for _, event := range calendar.Events() {
+			for _, attendee := range event.Props["ATTENDEE"] {
+				attendee.Params.Set("RSVP", "FALSE")
+			}
+		}
+		var buf bytes.Buffer
+		if err := ical.NewEncoder(&buf).Encode(calendar); err == nil {
+			icsContent = buf.String()
+		}
+	}
+	if icsContent == "" {
+		icsContent = originalICS // Fallback to raw if decoding failed
+	}
+
+	// 3. Construct Multipart MIME Email
+	boundary := "nxcaldav_invite_boundary"
+	subject := fmt.Sprintf("Invitation: %s", summary)
+	
+	header := fmt.Sprintf("Subject: %s\r\n", subject)
+	header += fmt.Sprintf("From: %s\r\n", fromHeader)
+	header += fmt.Sprintf("To: %s\r\n", recipientEmail)
+	header += "MIME-Version: 1.0\r\n"
+	header += fmt.Sprintf("Content-Type: multipart/mixed; boundary=\"%s\"\r\n", boundary)
+	header += "\r\n"
+
+	body := fmt.Sprintf("--%s\r\n", boundary)
+	body += "Content-Type: text/plain; charset=UTF-8\r\n"
+	body += "Content-Transfer-Encoding: 7bit\r\n"
+	body += "\r\n"
+	body += textPart + "\r\n"
+
+	body += fmt.Sprintf("--%s\r\n", boundary)
+	body += "Content-Type: text/calendar; method=REQUEST; charset=UTF-8\r\n"
+	body += "Content-Transfer-Encoding: 7bit\r\n"
+	body += "\r\n"
+	body += icsContent + "\r\n"
+	body += fmt.Sprintf("--%s--\r\n", boundary)
+
+	// 4. Send the mail
+	addr := fmt.Sprintf("%s:%d", b.smtp.Host, b.smtp.Port)
+	tlsConfig := &tls.Config{InsecureSkipVerify: true, ServerName: b.smtp.Host}
+	
+	var c *smtp.Client
+	if b.smtp.Port == 465 {
+		conn, err := tls.Dial("tcp", addr, tlsConfig)
+		if err != nil { return err }
+		c, err = smtp.NewClient(conn, b.smtp.Host)
+	} else {
+		c, err = smtp.Dial(addr)
+	}
+	if err != nil { return err }
+	defer c.Close()
+
+	if err = c.Hello("localhost"); err != nil { return err }
+	if b.smtp.Port != 465 {
+		if ok, _ := c.Extension("STARTTLS"); ok {
+			if err = c.StartTLS(tlsConfig); err != nil { return err }
+		}
+	}
+	if b.smtp.User != "" && b.smtp.Password != "" {
+		auth := smtp.PlainAuth("", b.smtp.User, b.smtp.Password, b.smtp.Host)
+		if err = c.Auth(auth); err != nil { return err }
+	}
+
+	if err = c.Mail(fromAddr); err != nil { return err }
+	if err = c.Rcpt(recipientEmail); err != nil { return err }
+
+	w, err := c.Data()
+	if err != nil { return err }
+	_, err = w.Write([]byte(header + body))
+	if err != nil { return err }
+	err = w.Close()
+	if err != nil { return err }
+
+	log.Printf("[email] Successfully sent iMIP invitation to %s", recipientEmail)
+	return c.Quit()
+}

internal/config/config.go

@@ -18,6 +18,13 @@ type Access struct {
 }
 
 type Calendar struct {
+	ID     string   `yaml:"id"`
+	Owner  string   `yaml:"owner"`
+	Color  string   `yaml:"color,omitempty"`
+	Access []Access `yaml:"access,omitempty"`
+}
+
+type AddressBook struct {
 	ID     string   `yaml:"id"`
 	Owner  string   `yaml:"owner"`
 	Access []Access `yaml:"access,omitempty"`
@@ -26,6 +33,7 @@ type Calendar struct {
 type Aggregate struct {
 	ID      string   `yaml:"id"`
 	Owner   string   `yaml:"owner"`
+	Color   string   `yaml:"color,omitempty"`
 	Sources []string `yaml:"sources"` // Calendar IDs
 	Access  []Access `yaml:"access,omitempty"`
 }
@@ -44,25 +52,47 @@ type DatabaseConfig struct {
 type ServerConfig struct {
 	BindAddress  string `yaml:"bind_address"`
 	PublicURL    string `yaml:"public_url"`
-	Redaction    string `yaml:"redaction_text"`
-	DefaultClass string `yaml:"default_class"`
+	EmailDomain  string `yaml:"email_domain"`
+	Redaction    string `yaml:"redaction_text"` // "[-]"
+	DefaultClass string `yaml:"default_class"` // CONFIDENTIAL/PRIVATE/PUBLIC
 }
-
 func (s ServerConfig) BasePath() string {
 	u, err := url.Parse(s.PublicURL)
-	if err != nil {
-		return ""
-	}
+	if err != nil { return "" }
 	return strings.TrimSuffix(u.Path, "/")
 }
 
+
+type SMTPConfig struct {
+	Host     string `yaml:"host"`
+	Port     int    `yaml:"port"`
+	User     string `yaml:"user"`
+	Password string `yaml:"password"`
+}
+
 type Config struct {
 	Server       ServerConfig   `yaml:"server"`
 	Database     DatabaseConfig `yaml:"database"`
+	SMTP         SMTPConfig     `yaml:"smtp"`
 	Users        []User         `yaml:"users"`
 	Calendars    []Calendar     `yaml:"calendars"`
+	AddressBooks []AddressBook  `yaml:"address_books"`
 	Aggregates   []Aggregate    `yaml:"aggregates"`
 }
+func (c *Config) setDefaults() {
+	if c.Server.BindAddress == ""  { c.Server.BindAddress = ":8080" }
+	if c.Server.Redaction == ""    { c.Server.Redaction = "Busy" }
+	if c.Server.DefaultClass == "" { c.Server.DefaultClass = "CONFIDENTIAL" }
+	if c.Server.EmailDomain == ""  { c.Server.EmailDomain = "nx2.site" }
+	if c.Database.URL == ""        { c.Database.URL = "postgres://nxcaldav@localhost:5432/nxcaldav?sslmode=disable" }
+	if c.SMTP.Host == ""           { c.SMTP.Host = "localhost" }
+	if c.SMTP.Port == 0            { c.SMTP.Port = 25 }
+}
+func (c *Config) checkConfig() {
+	if !(slices.Contains([]string{"PUBLIC", "PRIVATE", "CONFIDENTIAL"}, c.Server.DefaultClass)) {
+		panic("Invaldi Config, default_class")
+	}
+}
 
 func Load(path string) (*Config, error) {
 	f, err := os.Open(path)
@@ -82,23 +112,3 @@ func Load(path string) (*Config, error) {
 	return &cfg, nil
 }
 
-func (c *Config) checkConfig() {
-	if !(slices.Contains([]string{"PUBLIC", "PRIVATE", "CONFIDENTIAL"}, c.Server.DefaultClass)) {
-		panic("Invaldi Config, default_class")
-	}
-}
-
-func (c *Config) setDefaults() {
-	if c.Server.BindAddress == "" {
-		c.Server.BindAddress = ":8080"
-	}
-	if c.Server.Redaction == "" {
-		c.Server.Redaction = "Busy"
-	}
-	if c.Server.DefaultClass == "" {
-		c.Server.DefaultClass = "CONFIDENTIAL"
-	}
-	if c.Database.URL == "" {
-		c.Database.URL = "postgres://nxcaldav@localhost:5432/nxcaldav?sslmode=disable"
-	}
-}

internal/extra/injector.go

@@ -0,0 +1,194 @@
+package extra
+
+import (
+	"bytes"
+	"strings"
+	"fmt"
+	"context"
+	"io"
+	"net/http"
+
+	"nxcaldav/internal/backend"
+	"regexp"
+	"time"
+)
+
+type responseWriter struct {
+	http.ResponseWriter
+	buffer *bytes.Buffer
+	status int
+}
+
+func (rw *responseWriter) Write(b []byte) (int, error) {
+	return rw.buffer.Write(b)
+}
+
+func (rw *responseWriter) WriteHeader(status int) {
+	rw.status = status
+}
+
+// Add Color To Calendar Propfind
+func InjectColor(r *http.Request, ctx context.Context, handler http.Handler, w http.ResponseWriter, be *backend.DBBackend) {
+	reqBody, _ := io.ReadAll(r.Body)
+	r.Body = io.NopCloser(bytes.NewBuffer(reqBody))
+
+	buf := &bytes.Buffer{}
+	rw := &responseWriter{w, buf, http.StatusOK}
+	handler.ServeHTTP(rw, r.WithContext(ctx))
+
+	body := buf.Bytes()
+	
+	// this models after the Radicale Response, largely AI code
+	// 1. Add namespaces to the root multistatus tag
+	reMultistatus := regexp.MustCompile(`(<[a-zA-Z0-9]*:?multistatus)`)
+	body = reMultistatus.ReplaceAll(body, []byte(`$1 xmlns:ICAL="http://apple.com/ns/ical/" xmlns:C="urn:ietf:params:xml:ns:caldav" xmlns:CS="http://calendarserver.org/ns/"`))
+
+	// 2. Response processing
+	reResponse :=  regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?response.*?>.*?</[a-zA-Z0-9]*:?response>`)
+	reHref :=      regexp.MustCompile(`<[a-zA-Z0-9]*:?href.*?>(.*?)</[a-zA-Z0-9]*:?href>`)
+	rePropstat :=  regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?propstat.*?>.*?</[a-zA-Z0-9]*:?propstat>`)
+	reStatusOk :=  regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?status.*?>HTTP/1.1 200 OK</[a-zA-Z0-9]*:?status>`)
+	reProp :=      regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?prop.*?>.*?</[a-zA-Z0-9]*:?prop>`)
+	rePropClose := regexp.MustCompile(`</[a-zA-Z0-9]*:?prop>`)
+
+	body = reResponse.ReplaceAllFunc(body, func(resp []byte) []byte {
+		hrefMatch := reHref.FindSubmatch(resp)
+		if len(hrefMatch) < 2 {
+			return resp
+		}
+		href := string(hrefMatch[1])
+		color := be.GetColor(r.Context(), href)
+		if color == "" {
+			return resp
+		}
+
+		// 1. Strip any existing conflicting tags that might be in 404 blocks
+		reStrip := regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?(calendar-color|getctag|calendar-order).*?/>|<[a-zA-Z0-9]*:?(calendar-color|getctag|calendar-order).*?>.*?</[a-zA-Z0-9]*:?(calendar-color|getctag|calendar-order)>`)
+		resp = reStrip.ReplaceAll(resp, []byte(""))
+
+		fullColor := strings.ToLower(color)
+		if len(fullColor) == 7 && strings.HasPrefix(fullColor, "#") {
+			fullColor += "ff"
+		}
+		// Prepare the properties to inject
+		props := fmt.Sprintf("<ICAL:calendar-color>%s</ICAL:calendar-color>", fullColor)
+		props += fmt.Sprintf("<C:calendar-color>%s</C:calendar-color>", fullColor)
+		props += "<ICAL:calendar-order>0</ICAL:calendar-order>"
+		props += fmt.Sprintf("<CS:getctag>\"%d\"</CS:getctag>", time.Now().Unix())
+
+		// 2. Try to inject into an existing 200 OK propstat
+		has200 := false
+		resp = rePropstat.ReplaceAllFunc(resp, func(ps []byte) []byte {
+			if reStatusOk.Match(ps) {
+				has200 = true
+				return reProp.ReplaceAllFunc(ps, func(prop []byte) []byte {
+					return rePropClose.ReplaceAllFunc(prop, func(closeTag []byte) []byte {
+						return append([]byte(props), closeTag...)
+					})
+				})
+			}
+			return ps
+		})
+
+		// 3. If no 200 OK propstat was found, create one
+		if !has200 {
+			newPropstat := fmt.Sprintf("<propstat xmlns=\"DAV:\"><prop>%s</prop><status>HTTP/1.1 200 OK</status></propstat>", props)
+			reResponseClose := regexp.MustCompile(`</[a-zA-Z0-9]*:?response>`)
+			resp = reResponseClose.ReplaceAllFunc(resp, func(closeTag []byte) []byte {
+				return append([]byte(newPropstat), closeTag...)
+			})
+		}
+
+		return resp
+	})
+
+	w.Header().Set("Content-Length", fmt.Sprintf("%d", len(body)))
+	w.WriteHeader(rw.status)
+	w.Write(body)
+}
+
+// modify caledar probfind
+//
+// this again modeled after the Radicale response
+// Largly AI generated agian
+func HandleDiscoveryPropfind(r *http.Request, ctx context.Context, handler http.Handler, w http.ResponseWriter, be *backend.DBBackend) {
+	reqBody, _ := io.ReadAll(r.Body)
+	r.Body = io.NopCloser(bytes.NewBuffer(reqBody))
+
+	buf := &bytes.Buffer{}
+	rw := &responseWriter{w, buf, http.StatusOK}
+	handler.ServeHTTP(rw, r.WithContext(ctx))
+
+	body := buf.Bytes()
+
+	// 1. Unconditionally add namespaces to root tag
+	reMultistatus := regexp.MustCompile(`(<[a-zA-Z0-9]*:?multistatus)`)
+	body = reMultistatus.ReplaceAll(body, []byte(`$1 xmlns:C="urn:ietf:params:xml:ns:caldav" xmlns:card="urn:ietf:params:xml:ns:carddav"`))
+
+	// 2. Response processing
+	reResponse := regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?response.*?>.*?</[a-zA-Z0-9]*:?response>`)
+	reHref := regexp.MustCompile(`<[a-zA-Z0-9]*:?href.*?>(.*?)</[a-zA-Z0-9]*:?href>`)
+	rePropstat := regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?propstat.*?>.*?</[a-zA-Z0-9]*:?propstat>`)
+	reStatusOk := regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?status.*?>HTTP/1.1 200 OK</[a-zA-Z0-9]*:?status>`)
+	reProp := regexp.MustCompile(`(?s)<[a-zA-Z0-9]*:?prop.*?>.*?</[a-zA-Z0-9]*:?prop>`)
+	rePropClose := regexp.MustCompile(`</[a-zA-Z0-9]*:?prop>`)
+
+	body = reResponse.ReplaceAllFunc(body, func(resp []byte) []byte {
+		hrefMatch := reHref.FindSubmatch(resp)
+		if len(hrefMatch) < 2 {
+			return resp
+		}
+
+		calHome, _ := be.CalendarHomeSetPath(ctx)
+		cardHome, _ := be.AddressBookHomeSetPath(ctx)
+
+		// Strip these tags ONLY from non-200 propstats
+		resp = rePropstat.ReplaceAllFunc(resp, func(ps []byte) []byte {
+			if !reStatusOk.Match(ps) {
+				reTags := regexp.MustCompile(`(?s)<[a-zA-Z0-9:]*(calendar-home-set|addressbook-home-set).*?/>|<[a-zA-Z0-9:]*(calendar-home-set|addressbook-home-set).*?>.*?</[a-zA-Z0-9:]*(calendar-home-set|addressbook-home-set)>`)
+				return reTags.ReplaceAll(ps, []byte(""))
+			}
+			return ps
+		})
+
+		props := ""
+		if calHome != "" && !strings.Contains(string(resp), "calendar-home-set") {
+			props += fmt.Sprintf("<C:calendar-home-set><href xmlns=\"DAV:\">%s</href></C:calendar-home-set>", calHome)
+		}
+		if cardHome != "" && !strings.Contains(string(resp), "addressbook-home-set") {
+			props += fmt.Sprintf("<card:addressbook-home-set><href xmlns=\"DAV:\">%s</href></card:addressbook-home-set>", cardHome)
+		}
+
+		if props == "" {
+			return resp
+		}
+
+		// 2. Try to inject into an existing 200 OK propstat
+		has200 := false
+		resp = rePropstat.ReplaceAllFunc(resp, func(ps []byte) []byte {
+			if reStatusOk.Match(ps) {
+				has200 = true
+				return reProp.ReplaceAllFunc(ps, func(prop []byte) []byte {
+					return rePropClose.ReplaceAllFunc(prop, func(closeTag []byte) []byte {
+						return append([]byte(props), closeTag...)
+					})
+				})
+			}
+			return ps
+		})
+
+		// 3. If no 200 OK propstat was found, create one
+		if !has200 {
+			newPropstat := fmt.Sprintf("<propstat xmlns=\"DAV:\"><prop>%s</prop><status>HTTP/1.1 200 OK</status></propstat>", props)
+			reResponseClose := regexp.MustCompile(`</[a-zA-Z0-9]*:?response>`)
+			resp = reResponseClose.ReplaceAllFunc(resp, func(closeTag []byte) []byte {
+				return append([]byte(newPropstat), closeTag...)
+			})
+		}
+		return resp
+	})
+
+	w.Header().Set("Content-Length", fmt.Sprintf("%d", len(body)))
+	w.WriteHeader(rw.status)
+	w.Write(body)
+}

main.go

@@ -4,53 +4,67 @@ import (
 	"context"
 	"fmt"
 	"log"
-	"os"
 	"net/http"
 	"net/url"
+	"os"
+	"slices"
 	"strings"
 	"time"
 
 	"github.com/emersion/go-webdav/caldav"
+	"github.com/emersion/go-webdav/carddav"
+
 	"nxcaldav/internal/backend"
 	"nxcaldav/internal/config"
+	"nxcaldav/internal/extra"
 )
 
 func main() {
-	path := "config.yaml";
-	if len(os.Args) != 0 {
+	// -- GET CONFIG
+	path := "config.yaml"
+	if len(os.Args) == 3 {
 		if os.Args[1] == "-c" {
 			path = os.Args[2]
 		}
 	}
-	cfg, err := config.Load()
+	cfg, err := config.Load(path)
 	if err != nil {
 		log.Fatalf("failed to load config: %v", err)
 	}
 
+	// -- GET CONTEXT AND DB
 	ctx := context.Background()
 	be, err := backend.NewDBBackend(ctx, cfg)
 	if err != nil {
 		log.Fatalf("failed to initialize database backend: %v", err)
 	}
 
-	handler := &caldav.Handler{Backend: be}
-
+	// -- GET CONTEXT AND DB
+	caldavHandler := &caldav.Handler{Backend: be}
+	carddavHandler := &carddav.Handler{Backend: be}
 	publicURL, _ := url.Parse(cfg.Server.PublicURL)
 
+	// -- DISCOVERIES
 	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
-		// Proxy-aware normalization:
+
+		scheme := r.URL.Scheme
+		if scheme == "" {
+			scheme = "http"
+		}
+
+		// set host (because reverse proxies exist)
 		if publicURL != nil && publicURL.Host != "" {
 			r.Host = publicURL.Host
 			r.URL.Host = publicURL.Host
 
-			// Detect scheme: prioritize X-Forwarded-Proto, then PublicURL
-			scheme := publicURL.Scheme
+			// prioritize X-Forwarded-Proto, then PublicURL (e.g. Cloudfalre proxy)
+			scheme = publicURL.Scheme
 			if proto := r.Header.Get("X-Forwarded-Proto"); proto != "" {
 				scheme = proto
 			}
 			r.URL.Scheme = scheme
 
-			// Also rewrite WebDAV Destination header (used for MOVE/COPY)
+			// Also rewrite WebDAV Destination header (for MOVE/COPY)
 			if dest := r.Header.Get("Destination"); dest != "" {
 				destURL, err := url.Parse(dest)
 				if err == nil {
@@ -61,58 +75,94 @@ func main() {
 			}
 		}
 
+		// public ics access
 		prefix := cfg.Server.BasePath()
 		if strings.HasPrefix(r.URL.Path, prefix+"/public/") {
 			be.ServePublicICS(w, r)
 			return
 		}
 
+		// DAV needs auth
 		user, password, ok := r.BasicAuth()
 		if !ok {
 			w.Header().Set("WWW-Authenticate", `Basic realm="CalDAV Server"`)
 			http.Error(w, "Unauthorized", http.StatusUnauthorized)
 			return
 		}
-
-		// Verify via Database (bcrypt)
 		valid, err := be.VerifyUser(r.Context(), user, password)
 		if err != nil {
 			log.Printf("auth error for %s: %v", user, err)
 			http.Error(w, "Internal Server Error", http.StatusInternalServerError)
 			return
 		}
-
 		if !valid {
 			log.Printf("auth failed for %s", user)
 			http.Error(w, "Unauthorized", http.StatusUnauthorized)
 			return
 		}
 
-		log.Printf("%s %s (user: %s)", r.Method, r.URL.Path, user)
-		prefix = cfg.Server.BasePath()
+		log.Printf("[user: %s] %s %s", user, r.Method, r.URL.Path)
+
 		principalPath := prefix + fmt.Sprintf("/%s/", user)
 		ctx := context.WithValue(r.Context(), "principal", principalPath)
 
-		if r.URL.Path == "/.well-known/caldav" || r.URL.Path == prefix+"/.well-known/caldav" {
-			// If we normalized the request, use the normalized host/scheme for the redirect
-			if publicURL != nil && publicURL.Host != "" {
-				scheme := r.URL.Scheme
-				if scheme == "" {
-					scheme = "http"
-				}
-				target := fmt.Sprintf("%s://%s%s", scheme, r.Host, principalPath)
-				http.Redirect(w, r, target, http.StatusMovedPermanently)
-			} else {
-				http.Redirect(w, r, principalPath, http.StatusMovedPermanently)
+		// set header for carddav
+		if slices.Contains([]string{
+			"/.well-known/carddav",
+			prefix + "/.well-known/carddav",
+			principalPath,
+			strings.TrimSuffix(principalPath, "/"),
+		}, r.URL.Path) || strings.Contains(r.URL.Path, "/addressbooks/") {
+			w.Header().Add("DAV", "addressbook")
 		}
+
+		// for caldav discovery
+		if slices.Contains([]string{
+			"/.well-known/caldav",
+			prefix + "/.well-known/caldav",
+		}, r.URL.Path) {
+			http.Redirect(w, r, fmt.Sprintf("%s://%s%s", scheme, r.Host, principalPath), http.StatusMovedPermanently)
 			return
 		}
 
+		// serve caldav
+		if strings.Contains(r.URL.Path, "/calendars/") {
+			if r.Method == "PROPFIND" {
+				// Calendar colors
+				// needed because color info is not RFC, so I hacked it in with regex, to look like Radicales response
+				extra.InjectColor(r, ctx, caldavHandler, w, be)
+			} else {
+				caldavHandler.ServeHTTP(w, r.WithContext(ctx))
+			}
 
-		handler.ServeHTTP(w, r.WithContext(ctx))
+			// serve carddav
+		} else if strings.Contains(r.URL.Path, "/addressbooks/") {
+			carddavHandler.ServeHTTP(w, r.WithContext(ctx))
+
+			// catch weird requests
+		} else {
+
+			if strings.HasSuffix(r.URL.Path, user+"/") || strings.HasSuffix(r.URL.Path, user) {
+				// For principal path, use merged discovery handler
+				if r.Method == "PROPFIND" {
+					extra.HandleDiscoveryPropfind(r, ctx, caldavHandler, w, be)
+				} else {
+					caldavHandler.ServeHTTP(w, r.WithContext(ctx))
+					// Ensure DAV header includes addressbook for OPTIONS
+					if r.Method == "OPTIONS" {
+						dav := w.Header().Get("DAV")
+						if dav != "" && !strings.Contains(dav, "addressbook") {
+							w.Header().Set("DAV", dav+", addressbook")
+						}
+					}
+				}
+			} else {
+				http.NotFound(w, r)
+			}
+		}
 	})
 
-	fmt.Printf("Starting CalDAV server on %s...\n", cfg.Server.BindAddress)
+	fmt.Printf("Starting CalDAV/CardDAV server on %s...\n", cfg.Server.BindAddress)
 	server := &http.Server{
 		Addr:         cfg.Server.BindAddress,
 		ReadTimeout:  30 * time.Second,

shell.nix

@@ -5,6 +5,7 @@
     ics
     caldav
     pyyaml
+    psycopg2
   ]);
 in pkgs.mkShell {
   buildInputs = [ python-with-my-packages ];