// mkdir.c, version 1.0.4
// OMKOV coreutils implementation of POSIX mkdir
// Copyright (C) 2020, Jakob Wakeling
// MIT Licence

/*
	TODO Cleanup p flag handling
	TODO Handle copying permissions
*/

#include "util/error.h"
#include "util/mode.h"
#include "util/optget.h"

#include <sys/stat.h>

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

#define VERSION "1.0.4"

static struct lop lops[] = {
	{ "help",    ARG_NUL, 256 },
	{ "version", ARG_NUL, 257 },
	{ NULL, 0, 0 }
};

static char *mopt;
static bool  pflag;

static mode_t mask;

static inline int makedir(const char *path, chmod_t *m);

static void hlp(void);
static void ver(void);

int main(int ac, char *av[]) { A0 = av[0];
	struct opt opt = OPTGET_INIT; opt.str = "m:p"; opt.lops = lops;
	for (int o; (o = optget(&opt, av, 1)) != -1;) switch (o) {
	case 'm': { mopt = opt.arg; break; }
	case 'p': { pflag = true; break; }
	case 256: { hlp(); return 0; }
	case 257: { ver(); return 0; }
	default: { return 1; }
	}
	
	if (opt.ind == ac) { error(1, "missing operand"); }
	
	chmod_t *m = NULL; if (mopt) {
		mask = umask(0); m = strmode(mopt);
		if (!m) { error(1, "%s: invalid mode", mopt); }
	}
	
	bool warned = false;
	
	for (char **p = &av[opt.ind]; *p; ++p) {
		if (pflag) { // Create directory hierarchy if p flag is set
			char *q = *p; for (; *q == '/'; ++q) {}
			for (; *q; ++q) {
				if (*q != '/' || *(q + 1) == '/') { continue; } *q = 0;
				if (mkdir(*p, (S_IWUSR | S_IXUSR | ~mask) & 0777) &&
						errno != EEXIST) {
					warn("%s: %s", *p, serr()); continue;
				} *q = '/';
			}
		}
		
		if (makedir(*p, m)) { warn("%s: %s", *p, serr()); warned = true; }
	}
	
	free(m); return warned;
}

/* Make directory with specified permissions */
static inline int makedir(const char *path, chmod_t *m) {
	// If no chmod is given, use default mode
	if (!m) { if (mkdir(path, 0777)) { return 1; } return 0; }
	
	// Create directory with no permissions
	if (mkdir(path, 0)) { return 1; } mode_t mode = 0777;
	
	// Handle each chmod_t
	for (int i = 0;; ++i) switch (m[i].flag) {
	case MF_NORM: case MF_XIFX: {
		// If ref is null, use the file mode creation mask
		if (!m[i].ref) { m[i].ref = M_ALL & ~mask; }
		
		switch (m[i].op) {
		case '+': { mode |= m[i].ref & m[i].mod; break; }
		case '-': { mode &= (~(m[i].ref & m[i].mod) & 07777); break; }
		case '=': { mode &= ~m[i].ref; mode |= m[i].ref & m[i].mod; break; }
		}
		
		// If the XIFX flag is set, set execute permission
		if (m[i].flag == MF_XIFX) { mode |= m[i].ref & M_EX; } break;
	}
	case MF_COPY: { /* TODO */ }
	case MF_NULL: { goto end; }
	} end:;
	
	// Set permissions of directory to the calculated mode
	if (chmod(path, mode)) { return 1; } return 0;
}

/* Print help information */
static void hlp(void) {
	puts("mkdir - make directories\n");
	puts("usage: mkdir [-p] [-m mode] dir...\n");
	puts("options:");
	puts("  -p         Create all parent directories as required");
	puts("  -m mode    Set the file mode of the created directory");
	puts("  --help     Display help information");
	puts("  --version  Display version information");
}

/* Print version information */
static void ver(void) {
	puts("OMKOV coreutils mkdir, version " VERSION);
	puts("Copyright (C) 2020, Jakob Wakeling");
	puts("MIT Licence (https://opensource.org/licenses/MIT)");
}