TUI-based service discovery for ascii-chat client. More...

Data Structures
struct	discovery_tui_server_t
	Discovered server information from mDNS. More...

struct	discovery_tui_config_t
	Configuration for TUI discovery. More...

Functions
discovery_tui_server_t *	discovery_tui_query (const discovery_tui_config_t config, int out_count)
	Discover ASCII-Chat servers on the local network via mDNS.

void	discovery_tui_free_results (discovery_tui_server_t *servers)
	Free results from TUI discovery query.

int	discovery_tui_prompt_selection (const discovery_tui_server_t *servers, int count)
	Display discovered servers to user and prompt for selection.

int	discovery_tui_select (const discovery_tui_server_t *servers, int count)
	TUI-based server selection with formatted display.

const char *	discovery_tui_get_best_address (const discovery_tui_server_t *server)
	Get best address representation for a discovered server.

Detailed Description

TUI-based service discovery for ascii-chat client.

Implements interactive mDNS-based discovery of ascii-chat servers on the local network. Provides a terminal UI for browsing and selecting available servers without manual IP entry.

Definition in file discovery_tui.h.

Function Documentation

◆ discovery_tui_free_results()

void discovery_tui_free_results ( discovery_tui_server_t * servers )

Free results from TUI discovery query.

Releases memory allocated by discovery_tui_query().

Parameters

servers Pointer to server array (safe to pass NULL)

Note: Safe to call multiple times or with NULL pointer

Free results from TUI discovery query.

Definition at line 45 of file discovery_tui.c.

                                                                 {
  discovery_mdns_free(servers);
}

References discovery_mdns_free().

Referenced by client_main().

◆ discovery_tui_get_best_address()

const char * discovery_tui_get_best_address ( const discovery_tui_server_t * server )

Get best address representation for a discovered server.

Returns the most suitable address representation (IPv4 > hostname > IPv6) for connecting to a discovered server.

Selection Priority:

IPv4 address (most universal)
Service name (if IPv4 not available)
IPv6 address (last resort)

Parameters

server Discovered server

Returns: Pointer to best address string (points to field in server struct)

Get best address representation for a discovered server.

Definition at line 206 of file discovery_tui.c.

                                                                                 {
  if (!server) {
    return "";
  }
 
  // Prefer IPv4 > name > IPv6
  if (server->ipv4[0] != '\0') {
    return server->ipv4;
  }
  if (server->name[0] != '\0') {
    return server->name;
  }
  if (server->ipv6[0] != '\0') {
    return server->ipv6;
  }
 
  return server->address; // Fallback to address field
}

References discovery_tui_server_t::address, discovery_tui_server_t::ipv4, discovery_tui_server_t::ipv6, and discovery_tui_server_t::name.

Referenced by client_main(), discovery_tui_prompt_selection(), and discovery_tui_select().

◆ discovery_tui_prompt_selection()

int discovery_tui_prompt_selection	(	const discovery_tui_server_t *	servers,
		int	count
	)

Display discovered servers to user and prompt for selection.

Shows a numbered list of discovered servers and prompts user to select one. Handles invalid input with re-prompting.

User Experience:

Available ASCII-Chat servers on LAN:
  1. swift-river-canyon (192.168.1.100:27224)
  2. quiet-mountain-lake (192.168.1.101:27224)
  3. gentle-forest-breeze (192.168.1.102:27224)
 
Select server (1-3) or press Enter to cancel: _

Behavior:

Displays each server with instance name and best-guess address
Shows IPv4 address if available, falls back to IPv6 or hostname
Handles non-numeric input with error message and re-prompt
Returns -1 if user presses Enter/Ctrl+C to cancel
Returns 0-based index of selected server

Parameters

servers	Array of discovered servers
count	Number of servers in array

Returns: Index of selected server (0 to count-1), or -1 to cancel

Note: This function performs interactive I/O - may not be suitable for automated contexts; For automated selection, use servers[0] directly instead

Display discovered servers to user and prompt for selection.

Definition at line 52 of file discovery_tui.c.

                                                                                     {
  if (!servers || count <= 0) {
    return -1;
  }
 
  // Display available servers
  printf("\nAvailable ASCII-Chat servers on LAN:\n");
  for (int i = 0; i < count; i++) {
    const discovery_tui_server_t *srv = &servers[i];
    const char *addr = discovery_tui_get_best_address(srv);
    printf("  %d. %s (%s:%u)\n", i + 1, srv->name, addr, srv->port);
  }
 
  // Prompt for selection
  printf("\nSelect server (1-%d) or press Enter to cancel: ", count);
  fflush(stdout);
 
  // Read user input
  char input[32];
  if (fgets(input, sizeof(input), stdin) == NULL) {
    printf("\n");
    return -1; // EOF or error
  }
 
  // Check for empty input (Enter pressed)
  if (input[0] == '\n' || input[0] == '\r' || input[0] == '\0') {
    return -1; // User cancelled
  }
 
  // Parse input as number
  char *endptr;
  long selection = strtol(input, &endptr, 10);
 
  // Validate input
  if (selection < 1 || selection > count) {
    printf("⚠️  Invalid selection. Please enter a number between 1 and %d\n", count);
    return discovery_tui_prompt_selection(servers, count); // Re-prompt
  }
 
  return (int)(selection - 1); // Convert to 0-based index
}

References discovery_tui_get_best_address(), discovery_tui_prompt_selection(), discovery_tui_server_t::name, and discovery_tui_server_t::port.

Referenced by discovery_tui_prompt_selection().

◆ discovery_tui_query()

discovery_tui_server_t * discovery_tui_query	(	const discovery_tui_config_t *	config,
		int *	out_count
	)

Discover ASCII-Chat servers on the local network via mDNS.

Performs an mDNS query for _ascii-chat._tcp services on the local network. Collects responses and returns discovered servers to the caller.

Behavior:

Sends multicast mDNS query for _ascii-chat._tcp.local services
Waits for responses for the specified timeout period
Collects all discovered servers with their addresses and ports
Returns array of discovered servers

Memory Management:

Caller is responsible for freeing the returned array with lan_discovery_free_results()
Returned servers are valid until lan_discovery_free_results() is called

Error Handling:

Returns NULL and sets errno on initialization failure
Partial results returned if mDNS init fails but discovery was attempted
Network errors logged but don't prevent continuation

Threading:

Blocking operation - waits for full timeout period
Safe to call from main thread
Does not spawn background threads

Parameters

config	Discovery configuration (NULL uses defaults)
out_count	Output parameter: number of discovered servers

Returns: Array of discovered servers, or NULL on error Must be freed with lan_discovery_free_results()

Note: Timeout includes network round-trip time, so 2000ms allows ~1.5s of actual waiting; Returns empty array (non-NULL with count=0) if no servers found, not NULL

Example:

discovery_tui_config_t config = {.timeout_ms = 2000, .max_servers = 20};
int count = 0;
discovery_tui_server_t *servers = discovery_tui_query(&config, &count);
 
if (servers && count > 0) {
    for (int i = 0; i < count; i++) {
        printf("%d: %s (%s:%d)\n", i+1, servers[i].name, servers[i].address, servers[i].port);
    }
    // User selects server...
    discovery_tui_free_results(servers);
}

Discover ASCII-Chat servers on the local network via mDNS.

Calls discovery_mdns_query() from discovery.c with TUI-friendly configuration.

Definition at line 25 of file discovery_tui.c.

                                                                                                  {
  if (!out_count) {
    SET_ERRNO(ERROR_INVALID_PARAM, "out_count pointer is NULL");
    return NULL;
  }
 
  *out_count = 0;
 
  // Apply defaults if needed
  int timeout_ms = (config && config->timeout_ms > 0) ? config->timeout_ms : 2000;
  int max_servers = (config && config->max_servers > 0) ? config->max_servers : 20;
  bool quiet = (config && config->quiet);
 
  // Call the core mDNS discovery function from discovery.c
  return discovery_mdns_query(timeout_ms, max_servers, quiet, out_count);
}

References discovery_mdns_query(), ERROR_INVALID_PARAM, discovery_tui_config_t::max_servers, discovery_tui_config_t::quiet, SET_ERRNO, and discovery_tui_config_t::timeout_ms.

Referenced by client_main().

◆ discovery_tui_select()

int discovery_tui_select	(	const discovery_tui_server_t *	servers,
		int	count
	)

TUI-based server selection with formatted display.

Displays discovered servers in a formatted terminal UI with:

Clear screen and boxed display
Server list with numbering and addresses
"No results" message if no servers available
Interactive numeric selection prompt

Display Example (3 servers):

╭─ 🔍 ASCII-Chat Server Discovery ────────────╮
│
│ Found 3 servers on your local network:
│
│   [1] swift-river-canyon     192.168.1.100:27224
│   [2] quiet-mountain-lake    192.168.1.101:27224
│   [3] gentle-forest-breeze   192.168.1.102:27224
│
╰────────────────────────────────────────────╯
 
Enter server number (1-3) or press Enter to cancel:

No Results Display:

╭─ 🔍 ASCII-Chat Server Discovery ─╮
│
│   No servers found on local network
│
│   Make sure an ASCII-Chat server is running on your LAN
│   Or provide a server address manually: ascii-chat client <address>
│
╰─────────────────────────────────────────╯

Parameters

servers	Array of discovered servers
count	Number of servers (0 for "no results")

Returns: 0-based index of selected server, or -1 to cancel

Displays discovered servers in a terminal UI with the following features:

Clears terminal and displays formatted server list
Shows "No results" message if no servers available
Allows numeric input for selection
Shows helpful prompts and icons

Parameters

servers	Array of discovered servers
count	Number of servers

Returns: 0-based index of selected server, or -1 to cancel

Definition at line 120 of file discovery_tui.c.

                                                                           {
  if (!servers || count <= 0) {
    // No servers found - return special code
    // Message will be printed at exit in client main
    return -1;
  }
 
  // Lock terminal to prevent concurrent logging from overwriting TUI
  bool prev_lock_state = log_lock_terminal();
 
  // Clear terminal
  log_plain("%s", ANSI_CLEAR);
 
  // Display header
  log_plain("\n");
  log_plain("%s╭─ 🔍 ASCII-Chat Server Discovery %s────────────╮%s\n", ANSI_BOLD, ANSI_RESET, ANSI_BOLD);
  log_plain("│%s\n", ANSI_RESET);
  log_plain("%s│%s Found %d server%s on your local network:%s\n", ANSI_BOLD, ANSI_GREEN, count, count == 1 ? "" : "s",
            ANSI_RESET);
  log_plain("%s│%s\n", ANSI_BOLD, ANSI_RESET);
 
  // Display server list with formatting
  for (int i = 0; i < count; i++) {
    const discovery_tui_server_t *srv = &servers[i];
    const char *addr = discovery_tui_get_best_address(srv);
 
    log_plain("%s│%s  ", ANSI_BOLD, ANSI_RESET);
    log_plain("%s[%d]%s %-30s %s%s:%u%s", ANSI_CYAN, i + 1, ANSI_RESET, srv->name, ANSI_YELLOW, addr, srv->port,
              ANSI_RESET);
    log_plain("\n");
  }
 
  log_plain("%s│%s\n", ANSI_BOLD, ANSI_RESET);
  log_plain("%s╰────────────────────────────────────────────╯%s\n", ANSI_BOLD, ANSI_RESET);
 
  // Prompt for selection
  log_plain("\n");
  log_plain("Enter server number (1-%d) or press Enter to cancel: ", count);
  fflush(stdout);
 
  // Unlock before waiting for input (user might take time)
  log_unlock_terminal(prev_lock_state);
 
  // Read user input
  char input[32];
  if (fgets(input, sizeof(input), stdin) == NULL) {
    return -1;
  }
 
  // Check for empty input (Enter pressed)
  if (input[0] == '\n' || input[0] == '\r' || input[0] == '\0') {
    return -1;
  }
 
  // Parse input as number
  char *endptr;
  long selection = strtol(input, &endptr, 10);
 
  // Validate input
  if (selection < 1 || selection > count) {
    printf("%sError:%s Please enter a number between 1 and %d\n\n", ANSI_YELLOW, ANSI_RESET, count);
    return discovery_tui_select(servers, count); // Re-prompt
  }
 
  // Lock terminal again for final output
  prev_lock_state = log_lock_terminal();
 
  // Clear screen and show connection status
  log_plain("%s", ANSI_CLEAR);
  log_plain("\n");
  log_plain("%s🔗 Connecting to %s...%s\n", ANSI_GREEN, servers[selection - 1].name, ANSI_RESET);
  log_plain("\n");
  fflush(stdout);
 
  // Brief delay so user can see the selection before logs overwrite it
  platform_sleep_ms(200);
 
  // Unlock terminal now that TUI is complete
  log_unlock_terminal(prev_lock_state);
 
  return (int)(selection - 1); // Convert to 0-based index
}

References ANSI_BOLD, ANSI_CLEAR, ANSI_CYAN, ANSI_GREEN, ANSI_RESET, ANSI_YELLOW, discovery_tui_get_best_address(), discovery_tui_select(), log_lock_terminal(), log_plain, log_unlock_terminal(), discovery_tui_server_t::name, platform_sleep_ms(), and discovery_tui_server_t::port.

Referenced by client_main(), and discovery_tui_select().

Data Structures

Functions

Detailed Description

Function Documentation

◆ discovery_tui_free_results()

◆ discovery_tui_get_best_address()

◆ discovery_tui_prompt_selection()

◆ discovery_tui_query()

◆ discovery_tui_select()