#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include "plugin.h"
#include "util/argconfig.h"

static int version(struct plugin *plugin)
{
	struct program *prog = plugin->parent;

	if (plugin->name)
		printf("%s %s version %s\n", prog->name, plugin->name, plugin->version);
	else
		printf("%s version %s\n", prog->name, prog->version);
	return 0;
}

static int help(int argc, char **argv, struct plugin *plugin)
{
	char man[0x100];
	struct program *prog = plugin->parent;
	char *str = argv[1];
	int i;

	if (argc == 1) {
		general_help(plugin);
		return 0;
	}

	for (i = 0; plugin->commands[i]; i++) {
		struct command *cmd = plugin->commands[i];

		if (strcmp(str, cmd->name))
			if (!cmd->alias || (cmd->alias && strcmp(str, cmd->alias)))
				continue;

		if (plugin->name)
			sprintf(man, "%s-%s-%s", prog->name, plugin->name, cmd->name);
		else
			sprintf(man, "%s-%s", prog->name, cmd->name);
		if (execlp("man", "man", man, (char *)NULL))
			perror(argv[1]);
	}
	return 0;
}

void usage(struct plugin *plugin)
{
	struct program *prog = plugin->parent;

	if (plugin->name)
		printf("usage: %s %s %s\n", prog->name, plugin->name, prog->usage);
	else
		printf("usage: %s %s\n", prog->name, prog->usage);
}

void general_help(struct plugin *plugin)
{
	struct program *prog = plugin->parent;
	struct plugin *extension;
	unsigned i = 0;
	unsigned padding = 15;
	unsigned curr_length = 0;
	printf("%s-%s\n", prog->name, prog->version);

	usage(plugin);

	printf("\n");
	print_word_wrapped(prog->desc, 0, 0);
	printf("\n");

	if (plugin->desc) {
		printf("\n");
		print_word_wrapped(plugin->desc, 0, 0);
		printf("\n");
	}

	printf("\nThe following are all implemented sub-commands:\n");

	/* iterate through all commands to get maximum length */
	/* Still need to handle the case of ultra long strings, help messages, etc */
	for (; plugin->commands[i]; i++)
		if (padding < (curr_length = 2 + strlen(plugin->commands[i]->name)))
			padding = curr_length;

	i = 0;
	for (; plugin->commands[i]; i++)
		printf("  %-*s %s\n", padding, plugin->commands[i]->name,
					plugin->commands[i]->help);

	printf("  %-*s %s\n", padding, "version", "Shows the program version");
	printf("  %-*s %s\n", padding, "help", "Display this help");
	printf("\n");

	if (plugin->name)
		printf("See '%s %s help <command>' for more information on a specific command\n",
			prog->name, plugin->name);
	else
		printf("See '%s help <command>' for more information on a specific command\n",
			prog->name);

	/* The first plugin is the built-in. If we're not showing help for the
	 * built-in, don't show the program's other extensions */
	if (plugin->name)
		return;

	extension = prog->extensions->next;
	if (!extension)
		return;

	printf("\nThe following are all installed plugin extensions:\n");
	while (extension) {
		printf("  %-*s %s\n", 15, extension->name, extension->desc);
		extension = extension->next;
	}
	printf("\nSee '%s <plugin> help' for more information on a plugin\n",
			prog->name);
}

int handle_plugin(int argc, char **argv, struct plugin *plugin)
{
	char *str = argv[0];
	char use[0x100];
	struct plugin *extension;
	struct program *prog = plugin->parent;
	struct command **cmd = plugin->commands;
	struct command *cr = NULL;
	bool cr_valid = false;

	if (!argc) {
		general_help(plugin);
		return 0;
	}

	if (!plugin->name)
		sprintf(use, "%s %s <device> [OPTIONS]", prog->name, str);
	else
		sprintf(use, "%s %s %s <device> [OPTIONS]", prog->name, plugin->name, str);
	argconfig_append_usage(use);

	/* translate --help and --version into commands */
	while (*str == '-')
		str++;

	if (!strcmp(str, "help"))
		return help(argc, argv, plugin);
	if (!strcmp(str, "version"))
		return version(plugin);

	while (*cmd) {
		if (!strcmp(str, (*cmd)->name) ||
		    ((*cmd)->alias && !strcmp(str, (*cmd)->alias)))
			return (*cmd)->fn(argc, argv, *cmd, plugin);
		if (!strncmp(str, (*cmd)->name, strlen(str))) {
			if (cr) {
				cr_valid = false;
			} else {
				cr = *cmd;
				cr_valid = true;
			}
		}
		cmd++;
	}

	if (cr && cr_valid) {
		sprintf(use, "%s %s <device> [OPTIONS]", prog->name, cr->name);
		argconfig_append_usage(use);
		return cr->fn(argc, argv, cr, plugin);
	}

	/* Check extensions only if this is running the built-in plugin */
	if (plugin->name) {
		printf("ERROR: Invalid sub-command '%s' for plugin %s\n", str, plugin->name);
		return -ENOTTY;
        }

	extension = plugin->next;
	while (extension) {
		if (!strcmp(str, extension->name))
			return handle_plugin(argc - 1, &argv[1], extension);
		extension = extension->next;
	}

	/* If the command is executed with the extension name and
	 * command together ("plugin-command"), run the plug in */
	extension = plugin->next;
	while (extension) {
		if (!strncmp(str, extension->name, strlen(extension->name))) {
			argv[0] += strlen(extension->name);
			while (*argv[0] == '-')
				argv[0]++;
			return handle_plugin(argc, &argv[0], extension);
		}
		extension = extension->next;
	}
	printf("ERROR: Invalid sub-command '%s'\n", str);
	return -ENOTTY;
}
