/* Provide system information

   LINUX: /proc file system
   Windows: GlobalMemoryStatusEx, GetSystemInfo, GetVersionExA, RegQueryValueExA

   Authors: Holger Vogt,  Hendrik Vogt

 */

#include "ngspice/ngspice.h"
#include "ngspice/cpdefs.h"
#include "ngspice/fteext.h"
#include "com_commands.h"

/* We might compile for Windows, but only as a console application (e.g. tcl) */
#if defined(HAS_WINGUI) || defined(__MINGW32__) || defined(_MSC_VER)
#define HAVE_WIN32
#endif

#ifdef HAVE_WIN32

#define WIN32_LEAN_AND_MEAN

#ifdef __MINGW32__  /* access to GlobalMemoryStatusEx in winbase.h:1558 */
#define WINVER 0x0500
#endif

#undef BOOLEAN
#include "windows.h"
#if defined(__MINGW32__) || (_MSC_VER > 1200) /* Exclude VC++ 6.0 from using the psapi */
#include <psapi.h>
#endif
#endif

#include "stdio.h"
#include "stdlib.h"
#include "string.h"

#define tInt int
#define TesError int
#define TES_FAIL 1
#define TES_SUCCESS 0
#define TES_INVALID_PARAMS 1

/* system info */
typedef struct TSI {
    char *cpuModelName;
    unsigned numPhysicalProcessors;
    unsigned numLogicalProcessors;
    char *osName;
} TesSystemInfo;

/* memory info */
struct sys_memory {
    unsigned long long size_m;  /* Total memory size */
    unsigned long long free_m;  /* Free memory */
    unsigned long long swap_t;  /* Swap total */
    unsigned long long swap_f;  /* Swap free */
};

static struct sys_memory mem_t_act;

TesError tesCreateSystemInfo(TesSystemInfo *info);
static int get_sysmem(struct sys_memory *memall);


/* Print to stream the given memory size in a human friendly format */
static void
fprintmem(FILE *stream, unsigned long long memory)
{
    if (memory > 1048576)
        fprintf(stream, "%8.6f MB", (double)memory /1048576.);
    else if (memory > 1024)
        fprintf(stream, "%5.3f kB", (double)memory / 1024.);
    else
        fprintf(stream, "%u bytes", (unsigned)memory);
}


static void
tesFreeSystemInfo(TesSystemInfo *info)
{
    if (info != NULL) {
        free(info->cpuModelName);
        free(info->osName);
    }
}


/* print system info */
void
com_sysinfo(wordlist *wl)
{
    int errorcode;
    TesSystemInfo *info;

    NG_IGNORE(wl);

    info = TMALLOC(TesSystemInfo, 1);

    errorcode = tesCreateSystemInfo(info);
    if (errorcode) {
        fprintf(cp_err, "No system info available! \n");
    } else {
        fprintf(cp_out, "\nOS: %s\n", info->osName);
        fprintf(cp_out, "CPU: %s\n", info->cpuModelName);
        if (info->numPhysicalProcessors > 0)
            fprintf(cp_out, "Physical processors: %u, ", info->numPhysicalProcessors);
        fprintf(cp_out, "Logical processors: %u\n",
                info->numLogicalProcessors);
    }
#if defined(HAVE_WIN32) || defined(HAVE__PROC_MEMINFO)

    get_sysmem(&mem_t_act);

    /* get_sysmem returns bytes */
    fprintf(cp_out, "Total DRAM available = ");
    fprintmem(cp_out, mem_t_act.size_m);
    fprintf(cp_out, ".\n");

    fprintf(cp_out, "DRAM currently available = ");
    fprintmem(cp_out, mem_t_act.free_m);
    fprintf(cp_out, ".\n\n");

#endif

    tesFreeSystemInfo(info);
    tfree(info);
}


#ifdef HAVE__PROC_MEMINFO

/* Get memory information */
static int
get_sysmem(struct sys_memory *memall)
{
    FILE *fp;
    char buffer[2048];
    size_t bytes_read;
    char *match;
    unsigned long mem_got;

    if ((fp = fopen("/proc/meminfo", "r")) == NULL) {
        perror("fopen(\"/proc/meminfo\")");
        return 0;
    }

    bytes_read = fread(buffer, 1, sizeof(buffer), fp);
    fclose(fp);
    if (bytes_read == 0 || bytes_read == sizeof(buffer))
        return 0;
    buffer[bytes_read] = '\0';

    /* Search for string "MemTotal" */
    match = strstr(buffer, "MemTotal");
    if (match == NULL) /* not found */
        return 0;
    sscanf(match, "MemTotal: %ld", &mem_got);
    memall->size_m = mem_got*1024; /* 1MB = 1024KB */
    /* Search for string "MemFree" */
    match = strstr(buffer, "MemFree");
    if (match == NULL) /* not found */
        return 0;
    sscanf(match, "MemFree: %ld", &mem_got);
    memall->free_m = mem_got*1024; /* 1MB = 1024KB */
    /* Search for string "SwapTotal" */
    match = strstr(buffer, "SwapTotal");
    if (match == NULL) /* not found */
        return 0;
    sscanf(match, "SwapTotal: %ld", &mem_got);
    memall->swap_t = mem_got*1024; /* 1MB = 1024KB */
    /* Search for string "SwapFree" */
    match = strstr(buffer, "SwapFree");
    if (match == NULL) /* not found */
        return 0;
    sscanf(match, "SwapFree: %ld", &mem_got);
    memall->swap_f = mem_got*1024; /* 1MB = 1024KB */
    return 1;
}


/* Return length of first line in a string */
static size_t
getLineLength(const char *str)
{
    const char *p = str;

    while (*p  &&  (*p != '\n'))
        p++;

    return (size_t) (p - str);
}


/* Checks if number 'match' is found in a vector 'set' of size 'size'
   Returns 1 if yes, otherwise, 0 */
static tInt
searchInSet(const tInt *set, unsigned size, tInt match)
{
    unsigned index;
    for (index = 0; index < size; index++)
        if (match == set[index])
            return 1;
    return 0;
}


/* Get system information */
TesError
tesCreateSystemInfo(TesSystemInfo *info)
{
    FILE *file;
    TesError error = TES_SUCCESS;

    if (info == NULL)
        return TES_INVALID_PARAMS;
    info->cpuModelName = NULL;
    info->osName = NULL;
    info->numLogicalProcessors = info->numPhysicalProcessors = 0;

    /* get kernel version string */
    file = fopen("/proc/version", "rb");
    if (file != NULL) {
        size_t size;

        /* read bytes and find end of file */
        for (size = 0; ; size++)
            if (EOF == fgetc(file))
                break;

        info->osName = TMALLOC(char, size);
        rewind(file);
        fread(info->osName, sizeof(char), size, file);
        fclose(file);

        info->osName[size-1] = '\0';
    } else {
        error = TES_FAIL;
    }

    /* get cpu information */
    file = fopen("/proc/cpuinfo", "rb");
    if (file != NULL) {
        size_t size;
        char *inStr;

        /* read bytes and find end of file */
        for (size = 0; ; size++)
            if (EOF == fgetc(file))
                break;

        /* get complete string */
        inStr = TMALLOC(char, size+1);
        rewind(file);
        fread(inStr, sizeof(char), size, file);
        inStr[size] = '\0';

        {
            const char *matchStr = "model name";
            /* pointer to first occurrence of model name*/
            const char *modelStr = strstr(inStr, matchStr);
            if (modelStr != NULL) {
                /* search for ':' */
                const char *modelPtr = strchr(modelStr, ':');
                if (modelPtr != NULL) {
                    /*length of string from ':' till end of line */
                    size_t numToEOL = getLineLength(modelPtr);
                    if (numToEOL > 2) {
                        /* skip ": "*/
                        numToEOL -= 2;
                        info->cpuModelName = TMALLOC(char, numToEOL+1);
                        memcpy(info->cpuModelName, modelPtr+2, numToEOL);
                        info->cpuModelName[numToEOL] = '\0';
                    }
                } else {
                    error = TES_FAIL;
                }
            } else {
                error = TES_FAIL;
            }
        }
        {
            const char *matchStrProc = "processor";
            const char *matchStrPhys = "physical id";
            char *strPtr = inStr;
            unsigned numProcs = 0;
            tInt *physIDs;

            /* get number of logical processors */
            while ((strPtr = strstr(strPtr, matchStrProc)) != NULL) {
                // numProcs++;
                strPtr += strlen(matchStrProc);
                if (isblank(*strPtr)) numProcs++;
            }
            info->numLogicalProcessors = numProcs;
            physIDs = TMALLOC(tInt, numProcs);

            /* get number of physical CPUs */
            numProcs = 0;
            strPtr = inStr;
            while ((strPtr = strstr(strPtr, matchStrProc)) != NULL) {

                /* search for first occurrence of physical id */
                strPtr = strstr(strPtr, matchStrPhys);
                if (strPtr != NULL) {
                    /* go to ';' */
                    strPtr = strchr(strPtr, ':');
                    if (strPtr != NULL) {
                        tInt buffer = 0;
                        /* skip ": " */
                        strPtr += 2;
                        /* get number */
                        sscanf(strPtr, "%d", &buffer);
                        /* If this  physical id is unique,
                           we have another physically available CPU */
                        if (searchInSet(physIDs, numProcs, buffer) == 0) {
                            physIDs[numProcs] = buffer;
                            numProcs++;
                        }
                    } else {
                        // error = TES_FAIL;
                        break;
                    }
                } else {
                    // error = TES_FAIL;
                    break;
                }
            }
            info->numPhysicalProcessors = numProcs;
            free(physIDs);
        }

        /* another test to get number of logical processors
         * if (info->numLogicalProcessors == 0) {
         *     char *token;
         *     char *cpustr = copy(inStr);
         *     while (cpustr && !*cpustr)
         *         if (cieq(gettok(&cpustr), "processor")) {
         *             gettok(&cpustr);
         *             token = gettok(&cpustr);
         *         }
         *
         *     info->numLogicalProcessors = atoi(token) + 1;
         *     tfree(cpustr);
         * }
         */

        free(inStr);
        fclose(file);
    } else {
        error = TES_FAIL;
    }

    return error;
}

#elif defined(HAVE_WIN32)

/* get memory information */
static int
get_sysmem(struct sys_memory *memall)
{
#if (_WIN32_WINNT >= 0x0500)
    MEMORYSTATUSEX ms;
    ms.dwLength = sizeof(MEMORYSTATUSEX);
    GlobalMemoryStatusEx(&ms);
    memall->size_m = ms.ullTotalPhys;
    memall->free_m = ms.ullAvailPhys;
    memall->swap_t = ms.ullTotalPageFile;
    memall->swap_f = ms.ullAvailPageFile;
#else
    MEMORYSTATUS ms;
    ms.dwLength = sizeof(MEMORYSTATUS);
    GlobalMemoryStatus(&ms);
    memall->size_m = ms.dwTotalPhys;
    memall->free_m = ms.dwAvailPhys;
    memall->swap_t = ms.dwTotalPageFile;
    memall->swap_f = ms.dwAvailPageFile;
#endif
    return 1;
}


/* get system information */
TesError
tesCreateSystemInfo(TesSystemInfo *info)
{
    OSVERSIONINFOA version;
    char *versionStr = NULL, *procStr, *freeStr;
    DWORD major, minor;
    DWORD dwLen;
    HKEY hkBaseCPU;
    LONG lResult;

    SYSTEM_INFO sysinfo;
    GetSystemInfo(&sysinfo);

    info->numPhysicalProcessors =  0;
    info->numLogicalProcessors = sysinfo.dwNumberOfProcessors; //atoi(getenv("NUMBER_OF_PROCESSORS"));
    info->osName = NULL;

    version.dwOSVersionInfoSize = sizeof(OSVERSIONINFOA);
    if (GetVersionExA(&version) == 0)
        return TES_FAIL;

    major = version.dwMajorVersion;
    minor = version.dwMinorVersion;
    switch (major) {
    case 4:
        if (minor == 0)
            versionStr = "Windows 95/NT4.0";
        else if (minor == 10)
            versionStr = "Windows 98";
        else if (minor == 90)
            versionStr = "Windows ME";
        break;
    case 5:
        if (minor == 0)
            versionStr = "Windows 2000";
        else if (minor == 1)
            versionStr = "Windows XP";
        else if (minor == 2)
            versionStr = "Windows Server 2003";
        break;
    case 6:
        if (minor == 0)
            versionStr = "Windows Vista";
        else if (minor == 1)
            versionStr = "Windows 7";
        break;
    default:
        break;
    }

    if (versionStr != NULL) {
        size_t lengthCSD = strlen(version.szCSDVersion);
        size_t lengthVer = strlen(versionStr);

        info->osName = TMALLOC(char, lengthVer + lengthCSD + 2);
        memcpy(info->osName, versionStr, lengthVer);
        memcpy(info->osName + lengthVer + 1, version.szCSDVersion, lengthCSD);
        info->osName[lengthVer] = ' ';
        info->osName[lengthVer + lengthCSD + 1] = '\0';
    }


    lResult = RegOpenKeyExA(HKEY_LOCAL_MACHINE,
                            "HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0",
                            0, KEY_READ, &hkBaseCPU);
    if (lResult != ERROR_SUCCESS) {
        info->cpuModelName = NULL;
        return TES_FAIL;
    }

    RegQueryValueExA(hkBaseCPU, "ProcessorNameString", 0, 0, NULL, &dwLen);
    freeStr = procStr = TMALLOC(char, dwLen + 1);
    RegQueryValueExA(hkBaseCPU, "ProcessorNameString", 0, 0, (LPBYTE)procStr, &dwLen);
    procStr[dwLen] = '\0';
    while (*procStr == ' ')
        procStr++;
    info->cpuModelName = copy(procStr);
    tfree(freeStr);

    RegCloseKey(hkBaseCPU);

    return TES_SUCCESS;
}

#else

/* no Windows OS, no proc info file system */
TesError
tesCreateSystemInfo(TesSystemInfo *info)
{
    return 1;
}

#endif