/*
 * Copyright 2004-2013, Axel Dörfler, axeld@pinc-software.de.
 * Copyright 2013, Paweł Dziepak, pdziepak@quarnos.org.
 * Distributed under the terms of the MIT License.
 */

/* Taken from the Pulse application, and extended.
 * It's used by Pulse, AboutHaiku, and sysinfo.
 */

#include <stdlib.h>
#include <stdio.h>
#include <strings.h>

#include <OS.h>


#ifdef __cplusplus
extern "C" {
#endif

static const char* get_cpu_vendor_string(enum cpu_vendor cpuVendor);
static const char* get_cpu_model_string(enum cpu_platform platform,
        enum cpu_vendor cpuVendor, uint32 cpuModel);
void get_cpu_type(char *vendorBuffer, size_t vendorSize,
                char *modelBuffer, size_t modelSize);
int32 get_rounded_cpu_speed(void);

#ifdef __cplusplus
}
#endif


#if defined(__i386__) || defined(__x86_64__)
/*!     Tries to parse an Intel CPU ID string to match our usual naming scheme.
        Note, this function is not thread safe, and must only be called once
        at a time.
*/
static const char*
parse_intel(const char* name)
{
        static char buffer[49];

        // ignore initial spaces
        int index = 0;
        for (; name[index] != '\0'; index++) {
                if (name[index] != ' ')
                        break;
        }


        // parse model
        int outIndex = 0;
        for (; name[index] != '\0'; index++) {
                // ignore vendor
                if (strncmp(&name[index], "Intel", 5) == 0) {
                        for (; name[index] != '\0'; index++) {
                                if (name[index] == ' ') {
                                        index++;
                                        break;
                                }
                        }
                }
                if (!strncmp(&name[index], "(R)", 3)) {
                        outIndex += strlcpy(&buffer[outIndex], "®",
                                sizeof(buffer) - outIndex);
                        index += 2;
                } else if (!strncmp(&name[index], "(TM)", 4)) {
                        outIndex += strlcpy(&buffer[outIndex], "™",
                                sizeof(buffer) - outIndex);
                        index += 3;
                } else if (!strncmp(&name[index], " CPU", 4)) {
                        // Cut out the CPU string
                        index += 3;
                } else if (!strncmp(&name[index], " @", 2)) {
                        // Cut off the remainder
                        break;
                } else
                        buffer[outIndex++] = name[index];
        }

        buffer[outIndex] = '\0';
        return buffer;
}


static const char*
parse_amd(const char* name)
{
        static char buffer[49];

        // ignore initial spaces
        int index = 0;
        for (; name[index] != '\0'; index++) {
                if (name[index] != ' ')
                        break;
        }

        // Keep an initial "mobile"
        int outIndex = 0;
        bool spaceWritten = false;
        if (!strncasecmp(&name[index], "Mobile ", 7)) {
                strcpy(buffer, "Mobile ");
                spaceWritten = true;
                outIndex += 7;
                index += 7;
        }

        // parse model
        for (; name[index] != '\0'; index++) {
                if (!strncasecmp(&name[index], "(r)", 3)) {
                        outIndex += strlcpy(&buffer[outIndex], "®",
                                sizeof(buffer) - outIndex);
                        index += 2;
                } else if (!strncasecmp(&name[index], "(tm)", 4)) {
                        outIndex += strlcpy(&buffer[outIndex], "™",
                                sizeof(buffer) - outIndex);
                        index += 3;
                } else if (!strncmp(&name[index], "with ", 5)
                        || !strncmp(&name[index], "/w", 2)) {
                        // Cut off the rest
                        break;
                } else if (name[index] == '-') {
                        if (!spaceWritten)
                                buffer[outIndex++] = ' ';
                        spaceWritten = true;
                } else {
                        const char* kWords[] = {
                                "Eight-core", "6-core", "Six-core", "Quad-core", "Dual-core",
                                "Dual core", "Processor", "APU", "AMD", "Intel", "Integrated",
                                "CyrixInstead", "Advanced Micro Devices", "Comb", "DualCore",
                                "Technology", "Mobile", "Triple-Core"
                        };
                        bool removed = false;
                        for (size_t i = 0; i < sizeof(kWords) / sizeof(kWords[0]); i++) {
                                size_t length = strlen(kWords[i]);
                                if (!strncasecmp(&name[index], kWords[i], length)) {
                                        index += length - 1;
                                        removed = true;
                                        break;
                                }
                        }
                        if (removed)
                                continue;

                        if (name[index] == ' ') {
                                if (spaceWritten)
                                        continue;
                                spaceWritten = true;
                        } else
                                spaceWritten = false;
                        buffer[outIndex++] = name[index];
                }
        }

        // cut off trailing spaces
        while (outIndex > 1 && buffer[outIndex - 1] == ' ')
                outIndex--;

        buffer[outIndex] = '\0';

        // skip new initial spaces
        for (outIndex = 0; buffer[outIndex] != '\0'; outIndex++) {
                if (buffer[outIndex] != ' ')
                        break;
        }
        return buffer + outIndex;
}
#endif


static const char*
get_cpu_vendor_string(enum cpu_vendor cpuVendor)
{
        // Should match vendors in OS.h
        static const char* vendorStrings[] = {
                NULL, "AMD", "Cyrix", "IDT", "Intel", "National Semiconductor", "Rise",
                "Transmeta", "VIA", "IBM", "Motorola", "NEC", "Hygon"
        };

        if ((size_t)cpuVendor >= sizeof(vendorStrings) / sizeof(const char*))
                return NULL;
        return vendorStrings[cpuVendor];
}


#if defined(__i386__) || defined(__x86_64__)
/*! Parameter 'name' needs to point to an allocated array of 49 characters. */
void
get_cpuid_model_string(char *name)
{
        /* References:
         *
         * http://grafi.ii.pw.edu.pl/gbm/x86/cpuid.html
         * http://www.sandpile.org/ia32/cpuid.htm
         * http://www.amd.com/us-en/assets/content_type/
         *      white_papers_and_tech_docs/TN13.pdf (Duron erratum)
         */

        cpuid_info baseInfo;
        cpuid_info cpuInfo;
        int32 maxStandardFunction, maxExtendedFunction = 0;

        memset(name, 0, 49 * sizeof(char));

        if (get_cpuid(&baseInfo, 0, 0) != B_OK) {
                /* This CPU doesn't support cpuid. */
                return;
        }

        maxStandardFunction = baseInfo.eax_0.max_eax;
        if (maxStandardFunction >= 500) {
                maxStandardFunction = 0;
                        /* Old Pentium sample chips have the CPU signature here. */
        }

        /* Extended cpuid */

        get_cpuid(&cpuInfo, 0x80000000, 0);
                /* hardcoded to CPU 0 */

        /* Extended cpuid is only supported if max_eax is greater than the */
        /* service id. */
        if (cpuInfo.eax_0.max_eax > 0x80000000)
                maxExtendedFunction = cpuInfo.eax_0.max_eax & 0xff;

        if (maxExtendedFunction >= 4) {
                int32 i;

                for (i = 0; i < 3; i++) {
                        cpuid_info nameInfo;
                        get_cpuid(&nameInfo, 0x80000002 + i, 0);

                        memcpy(name, &nameInfo.regs.eax, 4);
                        memcpy(name + 4, &nameInfo.regs.ebx, 4);
                        memcpy(name + 8, &nameInfo.regs.ecx, 4);
                        memcpy(name + 12, &nameInfo.regs.edx, 4);
                        name += 16;
                }
        }
}
#endif  /* __i386__ || __x86_64__ */


static const char*
get_cpu_model_string(enum cpu_platform platform, enum cpu_vendor cpuVendor,
        uint32 cpuModel)
{
#if defined(__i386__) || defined(__x86_64__)
        char cpuidName[49];
#endif

        (void)cpuVendor;
        (void)cpuModel;

#if defined(__i386__) || defined(__x86_64__)
        if (platform != B_CPU_x86 && platform != B_CPU_x86_64)
                return NULL;

        // XXX: This *really* isn't accurate. There is differing math
        // based on the CPU vendor.. Don't use these numbers anywhere
        // except "fast and dumb" identification of processor names.
        //
        // see cpuidtool.c to decode cpuid signatures (sysinfo) into a
        // value for this function.
        //
        // sysinfo has code in it which obtains the proper fam/mod/step ids

        uint16 family = ((cpuModel >> 8) & 0xf) | ((cpuModel >> 16) & 0xff0);
        uint16 model = ((cpuModel >> 4) & 0xf) | ((cpuModel >> 12) & 0xf0);
        uint8 stepping = cpuModel & 0xf;

        if (cpuVendor == B_CPU_VENDOR_AMD) {
                if (family == 5) {
                        if (model <= 3)
                                return "K5";
                        if (model <= 7)
                                return "K6";
                        if (model == 8)
                                return "K6-2";
                        if (model == 9 || model == 0xd)
                                return "K6-III";
                        if (model == 0xa)
                                return "Geode LX";
                } else if (family == 6) {
                        if (model <= 2 || model == 4)
                                return "Athlon";
                        if (model == 3)
                                return "Duron";
                        if (model <= 8 || model == 0xa)
                                return "Athlon XP";
                } else if (family == 0xf) {
                        if (model <= 4 || model == 7 || model == 8
                                || (model >= 0xb && model <= 0xf) || model == 0x14
                                || model == 0x18 || model == 0x1b || model == 0x1f
                                || model == 0x23 || model == 0x2b
                                || ((model & 0xf) == 0xf && model >= 0x2f && model <= 0x7e)) {
                                return "Athlon 64";
                        }
                        if (model == 5 || model == 0x15 || model == 0x21 || model == 0x25
                                || model == 0x27) {
                                return "Opteron";
                        }
                        if (model == 0x1c || model == 0x2c || model == 0x7f)
                                return "Sempron 64";
                        if (model == 0x24 || model == 0x4c || model == 0x68)
                                return "Turion 64";
                } else if (family == 0x1f) {
                        if (model == 2)
                                return "Phenom";
                        if ((model >= 4 && model <= 6) || model == 0xa) {
                                get_cpuid_model_string(cpuidName);
                                if (strcasestr(cpuidName, "Athlon") != NULL)
                                        return "Athlon II";
                                return "Phenom II";
                        }
                } else if (family == 0x3f)
                        return "A-Series";
                else if (family == 0x5f) {
                        if (model == 1)
                                return "C-Series";
                        if (model == 2)
                                return "E-Series";
                } else if (family == 0x6f) {
                        if (model == 1 || model == 2)
                                return "FX-Series";
                        if (model == 0x10 || model == 0x13)
                                return "A-Series";
                }

                // Fallback to manual parsing of the model string
                get_cpuid_model_string(cpuidName);
                return parse_amd(cpuidName);
        }

        if (cpuVendor == B_CPU_VENDOR_CYRIX) {
                if (family == 5 && model == 4)
                        return "GXm";
                if (family == 6)
                        return "6x86MX";
                return NULL;
        }

        if (cpuVendor == B_CPU_VENDOR_INTEL) {
                if (family == 5) {
                        if (model == 1 || model == 2)
                                return "Pentium";
                        if (model == 3 || model == 9)
                                return "Pentium OD";
                        if (model == 4 || model == 8)
                                return "Pentium MMX";
                } else if (family == 6) {
                        if (model == 1)
                                return "Pentium Pro";
                        if (model == 3 || model == 5)
                                return "Pentium II";
                        if (model == 6)
                                return "Celeron";
                        if (model == 7 || model == 8 || model == 0xa || model == 0xb)
                                return "Pentium III";
                        if (model == 9 || model == 0xd) {
                                get_cpuid_model_string(cpuidName);
                                if (strcasestr(cpuidName, "Celeron") != NULL)
                                        return "Pentium M Celeron";
                                return "Pentium M";
                        }
                        if (model == 0x1c || model == 0x26 || model == 0x36)
                                return "Atom";
                        if (model == 0xe) {
                                get_cpuid_model_string(cpuidName);
                                if (strcasestr(cpuidName, "Celeron") != NULL)
                                        return "Core Celeron";
                                return "Core";
                        }
                        if (model == 0xf || model == 0x17) {
                get_cpuid_model_string(cpuidName);
                                if (strcasestr(cpuidName, "Celeron") != NULL)
                                        return "Core 2 Celeron";
                                if (strcasestr(cpuidName, "Xeon") != NULL)
                                        return "Core 2 Xeon";
                                if (strcasestr(cpuidName, "Pentium") != NULL)
                                        return "Pentium";
                                if (strcasestr(cpuidName, "Extreme") != NULL)
                                        return "Core 2 Extreme";
                                return "Core 2";
                        }
                        if (model == 0x25) {
                                get_cpuid_model_string(cpuidName);
                                if (strcasestr(cpuidName, "i3") != NULL)
                                        return "Core i3";
                                return "Core i5";
                        }
                        if (model == 0x1a || model == 0x1e) {
                                get_cpuid_model_string(cpuidName);
                                if (strcasestr(cpuidName, "Xeon") != NULL)
                                        return "Core i7 Xeon";
                                return "Core i7";
                        }
                } else if (family == 0xf) {
                        if (model <= 4) {
                                get_cpuid_model_string(cpuidName);
                                if (strcasestr(cpuidName, "Celeron") != NULL)
                                        return "Pentium 4 Celeron";
                                if (strcasestr(cpuidName, "Xeon") != NULL)
                                        return "Pentium 4 Xeon";
                                return "Pentium 4";
                        }
                }

                // Fallback to manual parsing of the model string
                get_cpuid_model_string(cpuidName);
                return parse_intel(cpuidName);
        }

        if (cpuVendor == B_CPU_VENDOR_NATIONAL_SEMICONDUCTOR) {
                if (family == 5) {
                        if (model == 4)
                                return "Geode GX1";
                        if (model == 5)
                                return "Geode GX2";
                        return NULL;
                }
        }

        if (cpuVendor == B_CPU_VENDOR_RISE) {
                if (family == 5)
                        return "mP6";
                return NULL;
        }

        if (cpuVendor == B_CPU_VENDOR_TRANSMETA) {
                if (family == 5 && model == 4)
                        return "Crusoe";
                if (family == 0xf && (model == 2 || model == 3))
                        return "Efficeon";
                return NULL;
        }

        if (cpuVendor == B_CPU_VENDOR_VIA) {
                if (family == 5) {
                        if (model == 4)
                                return "WinChip C6";
                        if (model == 8)
                                return "WinChip 2";
                        if (model == 9)
                                return "WinChip 3";
                        return NULL;
                } else if (family == 6) {
                        if (model == 6)
                                return "C3 Samuel";
                        if (model == 7) {
                                if (stepping < 8)
                                        return "C3 Eden/Samuel 2";
                                return "C3 Ezra";
                        }
                        if (model == 8)
                                return "C3 Ezra-T";
                        if (model == 9) {
                                if (stepping < 8)
                                        return "C3 Nehemiah";
                                return "C3 Ezra-N";
                        }
                        if (model == 0xa || model == 0xd)
                                return "C7";
                        if (model == 0xf)
                                return "Nano";
                        return NULL;
                }
        }

#endif

        return NULL;
}


void
get_cpu_type(char *vendorBuffer, size_t vendorSize, char *modelBuffer,
        size_t modelSize)
{
        const char *vendor, *model;

        uint32 topologyNodeCount = 0;
        cpu_topology_node_info* topology = NULL;
        get_cpu_topology_info(NULL, &topologyNodeCount);
        if (topologyNodeCount != 0)
                topology = (cpu_topology_node_info*)calloc(topologyNodeCount, sizeof(cpu_topology_node_info));
        get_cpu_topology_info(topology, &topologyNodeCount);

        enum cpu_platform platform = B_CPU_UNKNOWN;
        enum cpu_vendor cpuVendor = B_CPU_VENDOR_UNKNOWN;
        uint32 cpuModel = 0;
        for (uint32 i = 0; i < topologyNodeCount; i++) {
                switch (topology[i].type) {
                        case B_TOPOLOGY_ROOT:
                                platform = topology[i].data.root.platform;
                                break;

                        case B_TOPOLOGY_PACKAGE:
                                cpuVendor = topology[i].data.package.vendor;
                                break;

                        case B_TOPOLOGY_CORE:
                                cpuModel = topology[i].data.core.model;
                                break;

                        default:
                                break;
                }
        }
        free(topology);

        vendor = get_cpu_vendor_string(cpuVendor);
        if (vendor == NULL)
                vendor = "Unknown";

        model = get_cpu_model_string(platform, cpuVendor, cpuModel);
        if (model == NULL)
                model = "Unknown";

        strlcpy(vendorBuffer, vendor, vendorSize);
        strlcpy(modelBuffer, model, modelSize);
}


int32
get_rounded_cpu_speed(void)
{
        uint32 topologyNodeCount = 0;
        cpu_topology_node_info* topology = NULL;
        get_cpu_topology_info(NULL, &topologyNodeCount);
        if (topologyNodeCount != 0)
                topology = (cpu_topology_node_info*)calloc(topologyNodeCount, sizeof(cpu_topology_node_info));
        get_cpu_topology_info(topology, &topologyNodeCount);

        uint64 cpuFrequency = 0;
        for (uint32 i = 0; i < topologyNodeCount; i++) {
                if (topology[i].type == B_TOPOLOGY_CORE) {
                                cpuFrequency = topology[i].data.core.default_frequency;
                                break;
                }
        }
        free(topology);

        int target, frac, delta;
        int freqs[] = { 100, 50, 25, 75, 33, 67, 20, 40, 60, 80, 10, 30, 70, 90 };
        uint x;

        target = cpuFrequency / 1000000;
        frac = target % 100;
        delta = -frac;

        for (x = 0; x < sizeof(freqs) / sizeof(freqs[0]); x++) {
                int ndelta = freqs[x] - frac;
                if (abs(ndelta) < abs(delta))
                        delta = ndelta;
        }
        return target + delta;
}