/* Copyright (C) 1998-99 Martin Baulig
   This file is part of LibGTop 1.0.

   Contributed by Martin Baulig <martin@home-of-linux.org>, April 1998.

   LibGTop is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License,
   or (at your option) any later version.

   LibGTop is distributed in the hope that it will be useful, but WITHOUT
   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   for more details.

   You should have received a copy of the GNU General Public License
   along with LibGTop; see the file COPYING. If not, write to the
   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.
*/

#include <config.h>
#include <glibtop/error.h>
#include <glibtop/cpu.h>
#include <glibtop/sysinfo.h>

#include "glibtop_private.h"

#define FILENAME "/proc/cpuinfo"

static const unsigned long _glibtop_sysdeps_sysinfo =
(1L << GLIBTOP_SYSINFO_CPUINFO);

static glibtop_sysinfo sysinfo = { .flags = 0 };

/* Lookup table for CPU part decoding */
static const struct {
    unsigned int part;
    const char *model;
} cpu_part_lookup[] = {
    { 0xd0b, "Cortex-A78" },
    { 0xd0c, "Cortex-X1" },
    { 0xd40, "Neoverse-N1" },
    { 0xd41, "Cortex-A78AE" },
    { 0xd42, "Cortex-A710" },
    { 0xd44, "Cortex-X2" },
    { 0xd4a, "Neoverse-V1" },
    { 0xd4b, "Neoverse-N2" },
    { 0xd4c, "Cortex-A715" },
    { 0xd4d, "Cortex-X3" },
    { 0xd49, "Cortex-A520" },
    { 0xd4e, "Cortex-A720" },
    { 0xd4f, "Cortex-X4" },
    { 0xd08, "Cortex-A55" },
    { 0x0000, "Unknown" } // Default fallback
};


/* Function to decode CPU part */
const char *decode_cpu_part(unsigned int part) {
    for (int i = 0; cpu_part_lookup[i].part != 0x0000; i++) {
        if (cpu_part_lookup[i].part == part) {
            return cpu_part_lookup[i].model;
        }
    }
    return "Unknown";
}

static void
init_sysinfo (glibtop *server)
{
	char* buffer;
	gchar ** processors;

	if(G_LIKELY(sysinfo.flags)) return;

	if (!g_file_get_contents(FILENAME, &buffer, NULL, NULL)) {
		glibtop_error_io_r(server, "g_file_get_contents(%s)", FILENAME);
	}

	/* cpuinfo records are seperated by a blank line */
	processors = g_strsplit(buffer, "\n\n", 0);

	g_free(buffer);

	sysinfo.ncpu = 0;
	for (char** this_proc = &processors[0]; *this_proc && **this_proc; this_proc++) {

		if (sysinfo.ncpu >= GLIBTOP_NCPU) {
			glibtop_warn_r(server, "Cannot deal with more than %d CPUs", GLIBTOP_NCPU);
			break;
		}

		gchar **parts, **p;
		if (g_strrstr (*this_proc, "processor" ) == NULL) {
		  /* skip unknown paragraph */
		  continue;
		}

		glibtop_entry * const cpuinfo = &sysinfo.cpuinfo[sysinfo.ncpu];

		cpuinfo->labels = g_ptr_array_new ();

		cpuinfo->values = g_hash_table_new_full(g_str_hash, g_str_equal,
							g_free, g_free);

		cpuinfo->descriptions = g_hash_table_new_full(g_str_hash, g_str_equal,
							g_free, g_free);

		/* "<key>    : <value>" */
		parts = g_strsplit_set(*this_proc, ":\n", 0);

		unsigned int cpu_part = 0;
        gboolean has_model = FALSE;

		for(p = parts; *p && *(p+1); p += 2) {

			/* stole the allocated memory */
			gchar * const key   = g_strstrip(   *p   );
			gchar * const value = g_strstrip( *(p+1) );

			g_ptr_array_add(cpuinfo->labels, key);
			g_hash_table_insert(cpuinfo->values, key, value);

			/* Extract CPU part */
            if (g_strcmp0(key, "CPU part") == 0) {
                cpu_part = strtoul(value, NULL, 16);
            }
            if (g_strcmp0(key, "model name") == 0) {
                has_model = TRUE;
            }
		}

		/* If model name is missing, add it */
        if (!has_model && cpu_part != 0) {
            const char *decoded_model = decode_cpu_part(cpu_part);
            g_hash_table_insert(cpuinfo->values, g_strdup("model name"), g_strdup(decoded_model));
        }

		/* the last key has no value and has not been added */
		if(*p) g_free(*p);

		/* just g_free instead of g_strvfree because we stole
		   the memory*/
		g_free(parts);

		sysinfo.ncpu++;
	}

	g_strfreev(processors);

	sysinfo.flags = _glibtop_sysdeps_sysinfo;
}

const glibtop_sysinfo *
glibtop_get_sysinfo_s (glibtop *server)
{
	init_sysinfo (server);
	return &sysinfo;
}