/* beastie - minimal system info */
#define VERSION "dev"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
#include <pwd.h>
#include <sys/utsname.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/statvfs.h>

/* module IDs - reference these in config.h modules[] */
enum module {
	MOD_SEP,        /* blank separator line */
	MOD_USERATHOST, /* user@hostname        */
	MOD_OS,         /* os name + release    */
	MOD_KERNEL,     /* kern.ident           */
	MOD_CPU,        /* hw.model             */
	MOD_UPTIME,     /* uptime               */
	MOD_MEM,        /* used / total memory  */
	MOD_SHELL,      /* $SHELL basename      */
	MOD_TERM,       /* $TERM                */
	MOD_WM,         /* wm (via xdpyinfo)    */
	MOD_DISK,       /* used / total on /    */
	MOD_PKGS,       /* pkg count            */
	MOD_RES,        /* screen resolution    */
	MOD_COLORS,     /* 16-color palette     */
};

#include "config.h"

#define ART_H  (int)(sizeof(ART)/sizeof(ART[0]))
#define NMOD   (int)(sizeof(modules)/sizeof(modules[0]))
#define MAX_INFO 32

/* format uptime as Xd Xh Xm from boot time */
static void
uptime_str(char *buf, size_t len)
{
	long up = 0;
	struct timeval bt;
	size_t sz = sizeof(bt);
	if (sysctlbyname("kern.boottime", &bt, &sz, NULL, 0) == 0)
		up = (long)(time(NULL) - bt.tv_sec);
	if (!up) { snprintf(buf, len, "unknown"); return; }
	long d = up / 86400, h = (up % 86400) / 3600, m = (up % 3600) / 60;
	if (d)      snprintf(buf, len, "%ldd %ldh %ldm", d, h, m);
	else if (h) snprintf(buf, len, "%ldh %ldm", h, m);
	else        snprintf(buf, len, "%ldm", m);
}

/* format memory as used / total in MB */
static void
mem_str(char *buf, size_t len)
{
	unsigned long total_mb = 0, used_mb = 0;
	unsigned long physmem;
	unsigned int free_c = 0, inactive_c = 0;
	int pgsz = 0;
	size_t sz;
	sz = sizeof(physmem);
	if (sysctlbyname("hw.physmem", &physmem, &sz, NULL, 0) == -1) {
		snprintf(buf, len, "unknown"); return;
	}
	/* available = free + inactive pages */
	sz = sizeof(free_c);     sysctlbyname("vm.stats.vm.v_free_count",     &free_c,     &sz, NULL, 0);
	sz = sizeof(inactive_c); sysctlbyname("vm.stats.vm.v_inactive_count", &inactive_c, &sz, NULL, 0);
	sz = sizeof(pgsz);       sysctlbyname("hw.pagesize",                  &pgsz,       &sz, NULL, 0);
	unsigned long avail = (unsigned long)(free_c + inactive_c) * pgsz;
	total_mb = physmem >> 20;
	used_mb  = (physmem - avail) >> 20;
	if (!total_mb) { snprintf(buf, len, "unknown"); return; }
	snprintf(buf, len, "%luM / %luM", used_mb, total_mb);
}

/* read cpu model string */
static void
cpu_str(char *buf, size_t len)
{
	size_t sz = len;
	if (sysctlbyname("hw.model", buf, &sz, NULL, 0) == 0) return;
	snprintf(buf, len, "unknown");
}

/* disk usage on / in GB used / total */
static void
disk_str(char *buf, size_t len)
{
	struct statvfs s;
	if (statvfs("/", &s) == -1) { snprintf(buf, len, "unknown"); return; }
	unsigned long long total = (unsigned long long)s.f_blocks * s.f_frsize;
	unsigned long long avail = (unsigned long long)s.f_bavail * s.f_frsize;
	unsigned long long used  = total - avail;
	snprintf(buf, len, "%.1fG / %.1fG",
	    (double)used  / (1024*1024*1024),
	    (double)total / (1024*1024*1024));
}

/* installed pkg count via pkg info */
static void
pkgs_str(char *buf, size_t len)
{
	FILE *f = popen("pkg info 2>/dev/null | wc -l", "r");
	if (f) {
		int n = 0;
		fscanf(f, "%d", &n);
		pclose(f);
		if (n > 0) { snprintf(buf, len, "%d (pkg)", n); return; }
	}
	snprintf(buf, len, "unknown");
}

/* screen resolution via xdpyinfo */
static void
res_str(char *buf, size_t len)
{
	FILE *f = popen("xdpyinfo 2>/dev/null | grep dimensions | awk '{print $2}'", "r");
	if (f) {
		char res[32] = {0};
		fgets(res, sizeof(res), f);
		pclose(f);
		size_t rl = strlen(res);
		if (rl && res[rl-1] == '\n') res[rl-1] = '\0';
		if (res[0]) { snprintf(buf, len, "%s", res); return; }
	}
	snprintf(buf, len, "unknown");
}

/* read custom kernel name via kern.ident sysctl */
static void
kernel_ident(char *buf, size_t len)
{
	size_t sz = len;
	if (sysctlbyname("kern.ident", buf, &sz, NULL, 0) == 0) return;
	snprintf(buf, len, "unknown");
}

int
main(int argc, char *argv[])
{
	if (argc == 2 && strcmp(argv[1], "--version") == 0) {
		printf("Beastie version " VERSION "\n");
		printf("Beastie is a minimal fetch tool for BSD systems.\n");
		printf("Compiled with "
#if defined(__clang__)
		    "clang " __clang_version__
#elif defined(__GNUC__)
		    "gcc " __VERSION__
#else
		    "unknown compiler"
#endif
		    "\n");
		return 0;
	}
	struct utsname uts;
	char cpu[256] = {0};
	char kid[64]  = {0};
	char upt[64]  = {0};
	char mem[64]  = {0};
	char dsk[64]  = {0};
	char pkg[64]  = {0};
	char res[64]  = {0};

	uname(&uts);

	/* prefer $USER env, fall back to passwd db */
	const char *user = getenv("USER");
	if (!user) {
		struct passwd *pw = getpwuid(getuid());
		user = pw ? pw->pw_name : "?";
	}

	cpu_str(cpu, sizeof(cpu));
	kernel_ident(kid, sizeof(kid));
	uptime_str(upt, sizeof(upt));
	mem_str(mem, sizeof(mem));
	disk_str(dsk, sizeof(dsk));
	pkgs_str(pkg, sizeof(pkg));
	res_str(res, sizeof(res));

	/* strip path prefix from $SHELL */
	const char *shell = getenv("SHELL");
	if (shell) { const char *s = strrchr(shell, '/'); if (s) shell = s + 1; }
	else shell = "unknown";

	/* normalize $TERM - strip -256color/-color suffix, map xterm generically */
	char termbuf[64] = "unknown";
	const char *termenv = getenv("TERM");
	if (termenv) {
		if (strncmp(termenv, "xterm", 5) == 0)
			snprintf(termbuf, sizeof(termbuf), "generic terminal emulator");
		else {
			char *p;
			snprintf(termbuf, sizeof(termbuf), "%s", termenv);
			if ((p = strstr(termbuf, "-256color"))) *p = '\0';
			else if ((p = strstr(termbuf, "-color")))    *p = '\0';
		}
	}
	const char *term = termbuf;

	/* detect x server vendor via xdpyinfo to avoid linking against libX11 */
	char wmbuf[64] = "none";
	if (getenv("DISPLAY")) {
		FILE *xdpy = popen("xdpyinfo 2>/dev/null | grep 'vendor string' | awk '{print $3}'", "r");
		if (xdpy) {
			char vendor[64] = {0};
			fgets(vendor, sizeof(vendor), xdpy);
			pclose(xdpy);
			size_t vl = strlen(vendor);
			if (vl && vendor[vl-1] == '\n') vendor[vl-1] = '\0';
			if (vendor[0])
				snprintf(wmbuf, sizeof(wmbuf), "dwm (on %s)", vendor);
			else
				snprintf(wmbuf, sizeof(wmbuf), "dwm");
		} else {
			snprintf(wmbuf, sizeof(wmbuf), "dwm");
		}
	}
	const char *wm = wmbuf;

	/* build info lines from modules[] */
	char ibufs[MAX_INFO][512];
	const char *ilines[MAX_INFO];
	int ni = 0;

	for (int j = 0; j < NMOD && ni < MAX_INFO; j++) {
		switch (modules[j]) {
		case MOD_SEP:
			ilines[ni++] = "";
			break;
		case MOD_USERATHOST:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_BOLD COLOR_USER "%s" COLOR_RESET
			    "@"
			    COLOR_BOLD COLOR_USER "%s" COLOR_RESET,
			    user, uts.nodename);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_OS:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "os    " COLOR_RESET " %s %s",
			    uts.sysname, uts.release);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_KERNEL:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "kernel" COLOR_RESET " %s", kid);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_CPU:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "cpu   " COLOR_RESET " %s", cpu);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_UPTIME:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "uptime" COLOR_RESET " %s", upt);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_MEM:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "mem   " COLOR_RESET " %s", mem);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_SHELL:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "shell " COLOR_RESET " %s", shell);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_TERM:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "term  " COLOR_RESET " %s", term);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_WM:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "wm    " COLOR_RESET " %s", wm);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_DISK:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "disk  " COLOR_RESET " %s", dsk);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_PKGS:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "pkgs  " COLOR_RESET " %s", pkg);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_RES:
			snprintf(ibufs[ni], sizeof(ibufs[0]),
			    COLOR_LABEL "res   " COLOR_RESET " %s", res);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		case MOD_COLORS: {
			/* render two rows of 8 color swatches each */
			char *p = ibufs[ni];
			size_t rem = sizeof(ibufs[0]);
			int n;
			for (int k = 0; k < 8; k++) {
				n = snprintf(p, rem, "\033[4%dm   ", k);
				p += n; rem -= n;
			}
			n = snprintf(p, rem, COLOR_RESET "  ");
			p += n; rem -= n;
			for (int k = 8; k < 16; k++) {
				n = snprintf(p, rem, "\033[48;5;%dm   ", k);
				p += n; rem -= n;
			}
			snprintf(p, rem, COLOR_RESET);
			ilines[ni] = ibufs[ni]; ni++;
			break;
		}
		}
	}

	/* print art + info side by side, padding whichever is shorter */
	int total = ni > ART_H ? ni : ART_H;

	printf("\n");
	for (int i = 0; i < total; i++) {
		printf("  ");
		if (i < ART_H)
			printf(COLOR_ART "%s" COLOR_RESET, ART[i]);
		else
			printf("%*s", ART_W, "");
		printf("   ");
		if (i < ni)
			printf("%s", ilines[i]);
		printf("\n");
	}

	return 0;
}