// SPDX-License-Identifier: GPL-2.0

// main.c - an entry point for this program.

//

// Copyright (c) 2018 Takashi Sakamoto <o-takashi@sakamocchi.jp>

//

// Originally written as 'aplay', by Michael Beck and Jaroslav Kysela.

//

// Licensed under the terms of the GNU General Public License, version 2.

#include "subcmd.h"

#include "misc.h"

#include "version.h"

#include <stdio.h>

#include <stdlib.h>

#include <stdbool.h>

#include <string.h>

enum subcmds {

	SUBCMD_TRANSFER = 0,

	SUBCMD_LIST,

	SUBCMD_HELP,

	SUBCMD_VERSION,

};

char *arg_duplicate_string(const char *str, int *err)

{

	char *ptr;

	// For safe.

	if (strlen(str) > 1024) {

		*err = -EINVAL;

		return NULL;

	}

	ptr = strdup(str);

	if (ptr == NULL)

		*err = -ENOMEM;

	return ptr;

}

long arg_parse_decimal_num(const char *str, int *err)

{

	long val;

	char *endptr;

	errno = 0;

	val = strtol(str, &endptr, 0);

	if (errno > 0) {

		*err = -errno;

		return 0;

	}

	if (*endptr != '\0') {

		*err = -EINVAL;

		return 0;

	}

	return val;

}

static void print_version(const char *const cmdname)

{

	printf("%s: version %s\n", cmdname, SND_UTIL_VERSION_STR);

}

static void print_help(void)

{

	printf(

"Usage:\n"

"  axfer transfer DIRECTION OPTIONS\n"

"  axfer list DIRECTION OPTIONS\n"

"  axfer version\n"

"  axfer help\n"

"\n"

"  where:\n"

"    DIRECTION = capture | playback\n"

"    OPTIONS = -h | --help | (subcommand specific)\n"

	);

}

// Backward compatibility to aplay(1).

static bool decide_subcmd(int argc, char *const *argv, enum subcmds *subcmd)

{

	static const struct {

		const char *const name;

		enum subcmds subcmd;

	} long_opts[] = {

		{"--list-devices",	SUBCMD_LIST},

		{"--list-pcms",		SUBCMD_LIST},

		{"--help",  		SUBCMD_HELP},

		{"--version",  		SUBCMD_VERSION},

	};

	static const struct {

		unsigned char c;

		enum subcmds subcmd;

	} short_opts[] = {

		{'l', SUBCMD_LIST},

		{'L', SUBCMD_LIST},

		{'h', SUBCMD_HELP},

	};

	char *pos;

	int i, j;

	if (argc == 1)

		return false;

	// Original command system. For long options.

	for (i = 0; i < ARRAY_SIZE(long_opts); ++i) {

		for (j = 0; j < argc; ++j) {

			if (!strcmp(long_opts[i].name, argv[j])) {

				*subcmd = long_opts[i].subcmd;

				return true;

			}

		}

	}

	// Original command system. For short options.

	for (i = 1; i < argc; ++i) {

		// Pick up short options only.

		if (argv[i][0] != '-' || argv[i][0] == '\0' ||

		    argv[i][1] == '-' || argv[i][1] == '\0')

			continue;

		for (pos = argv[i]; *pos != '\0'; ++pos) {

			for (j = 0; j < ARRAY_SIZE(short_opts); ++j) {

				if (*pos == short_opts[j].c) {

					*subcmd = short_opts[j].subcmd;

					return true;

				}

			}

		}

	}

	return false;

}

// Backward compatibility to aplay(1).

static bool decide_direction(int argc, char *const *argv,

			     snd_pcm_stream_t *direction)

{

	static const struct {

		const char *const name;

		snd_pcm_stream_t direction;

	} long_opts[] = {

		{"--capture",	SND_PCM_STREAM_CAPTURE},

		{"--playback",	SND_PCM_STREAM_PLAYBACK},

	};

	static const struct {

		unsigned char c;

		snd_pcm_stream_t direction;

	} short_opts[] = {

		{'C',		SND_PCM_STREAM_CAPTURE},

		{'P',		SND_PCM_STREAM_PLAYBACK},

	};

	static const char *const aliases[] = {

		[SND_PCM_STREAM_CAPTURE] = "arecord",

		[SND_PCM_STREAM_PLAYBACK] = "aplay",

	};

	int i, j;

	char *pos;

	// Original command system. For long options.

	for (i = 0; i < ARRAY_SIZE(long_opts); ++i) {

		for (j = 0; j < argc; ++j) {

			if (!strcmp(long_opts[i].name, argv[j])) {

				*direction = long_opts[i].direction;

				return true;

			}

		}

	}

	// Original command system. For short options.

	for (i = 1; i < argc; ++i) {

		// Pick up short options only.

		if (argv[i][0] != '-' || argv[i][0] == '\0' ||

		    argv[i][1] == '-' || argv[i][1] == '\0')

			continue;

		for (pos = argv[i]; *pos != '\0'; ++pos) {

			for (j = 0; j < ARRAY_SIZE(short_opts); ++j) {

				if (*pos == short_opts[j].c) {

					*direction = short_opts[j].direction;

					return true;

				}

			}

		}

	}

	// If not decided yet, judge according to command name.

	for (i = 0; i < ARRAY_SIZE(aliases); ++i) {

		for (pos = argv[0] + strlen(argv[0]); pos != argv[0]; --pos) {

			if (strstr(pos, aliases[i]) != NULL) {

				*direction = i;

				return true;

			}

		}

	}

	return false;

}

static bool detect_subcmd(int argc, char *const *argv, enum subcmds *subcmd)

{

	static const char *const subcmds[] = {

		[SUBCMD_TRANSFER] = "transfer",

		[SUBCMD_LIST] = "list",

		[SUBCMD_HELP] = "help",

		[SUBCMD_VERSION] = "version",

	};

	int i;

	if (argc < 2)

		return false;

	for (i = 0; i < ARRAY_SIZE(subcmds); ++i) {

		if (!strcmp(argv[1], subcmds[i])) {

			*subcmd = i;

			return true;

		}

	}

	return false;

}

static bool detect_direction(int argc, char *const *argv,

			     snd_pcm_stream_t *direction)

{

	if (argc < 3)

		return false;

	if (!strcmp(argv[2], "capture")) {

		*direction = SND_PCM_STREAM_CAPTURE;

		return true;

	}

	if (!strcmp(argv[2], "playback")) {

		*direction = SND_PCM_STREAM_PLAYBACK;

		return true;

	}

	return false;

}

int main(int argc, char *const *argv)

{

	snd_pcm_stream_t direction;

	enum subcmds subcmd;

	int err = 0;

	// For compatibility to aplay(1) implementation.

	if (strstr(argv[0], "arecord") == argv[0] + strlen(argv[0]) - 7 ||

	    strstr(argv[0], "aplay") == argv[0] + strlen(argv[0]) - 5) {

		if (!decide_direction(argc, argv, &direction))

			direction = SND_PCM_STREAM_PLAYBACK;

		if (!decide_subcmd(argc, argv, &subcmd))

			subcmd = SUBCMD_TRANSFER;

	} else {

		// The first option should be one of subcommands.

		if (!detect_subcmd(argc, argv, &subcmd))

			subcmd = SUBCMD_HELP;

		// The second option should be either 'capture' or 'direction'

		// if subcommand is neither 'version' nor 'help'.

		if (subcmd != SUBCMD_VERSION && subcmd != SUBCMD_HELP) {

			if (!detect_direction(argc, argv, &direction)) {

				subcmd = SUBCMD_HELP;

			} else {

				// argv[0] is needed for unparsed option to use

				// getopt_long(3).

				argc -= 2;

				argv += 2;

			}

		}

	}

	if (subcmd == SUBCMD_TRANSFER)

		err = subcmd_transfer(argc, argv, direction);

	else if (subcmd == SUBCMD_LIST)

		err = subcmd_list(argc, argv, direction);

	else if (subcmd == SUBCMD_VERSION)

		print_version(argv[0]);

	else

		print_help();

	if (err < 0)

		return EXIT_FAILURE;

	return EXIT_SUCCESS;

}