#include <stdarg.h> // va_list, va_start, va_end
#include <stdio.h> // FILE, stderr, stdout | vfprintf
#include <stdlib.h> // exit

#include "alloc.h"
#include "string.h"
#include "print.h"
#include "types.h"


void vprint(const char* format, va_list args) {
    ULE_TYPES_H_FTAG;
    vfprintf(stdout, format, args);
}

void vprintln(const char* format, va_list args) {
    ULE_TYPES_H_FTAG;
    vprint(format, args);
    print("\n");
}

/**
 * The entire purpose of this is so we don't have to #import <stdio.h> everywhere
 * +we intend to replace printf at some point with this
 */
void print(const char* format, ...) {
    ULE_TYPES_H_FTAG;
    if (format == null) { print("null"); return; }

    va_list args;
    va_start(args, format);

    vprint(format, args);

    va_end(args);
}

void println(const char* format, ...) {
    ULE_TYPES_H_FTAG;
    if (format == null) { print("null\n"); return; }

    va_list args;
    va_start(args, format);

    vprintln(format, args);

    va_end(args);
}

void printBitsLE(const size_t count, void* ptr) {
    u8* b = (u8*) ptr;
    u8 byte;
    for (s32 i = count - 1; i >= 0; i--) {
        for (s32 j = 7; j >= 0; j--) {
            byte = (b[i] >> j) & 1;
            print("%u", byte);
        }
    }
    println();
}

/**
 * Prints a stack trace.
 * Implementation varies for Win32 vs. *nix
 */
#define BACKTRACE_MAX_FRAMES 63
#ifdef _WIN32
#include <windows.h>
#include <dbghelp.h>
// if |string| is non-null, then the stack trace will be concatenated to it instead of being printed to stdout.
void trace(String* string) {
    ULE_TYPES_H_FTAG;

    #define BACKTRACE_MAX_FUNCTION_NAME_LENGTH 1024
    HANDLE processHandle = GetCurrentProcess();
    SymInitialize(processHandle, null, true);
    SymSetOptions(SYMOPT_LOAD_LINES);

    void* stack[BACKTRACE_MAX_FRAMES];
    unsigned short numFrames = CaptureStackBackTrace(0, BACKTRACE_MAX_FRAMES, stack, null);

    char buffer[sizeof(SYMBOL_INFO) + BACKTRACE_MAX_FUNCTION_NAME_LENGTH*sizeof(TCHAR)];
    SYMBOL_INFO* symbol = (SYMBOL_INFO*) buffer;
    symbol->MaxNameLen = BACKTRACE_MAX_FUNCTION_NAME_LENGTH;
    symbol->SizeOfStruct = sizeof(SYMBOL_INFO);

    // @TODO I believe that 'displacement' and line.LineNumber are supposed to be source code column numbers
    // and line numbers respectively, but displacement doesn't work at all (seems like) and line.LineNumber
    // is consistently off by a few lines. Perhaps it's post-processed source? I don't know. For now,
    // filename + line.LineNUmber are printed and we hope that's enough, and understand the line #s are only
    // approximate.
    DWORD displacement; 
    IMAGEHLP_LINE64 line;
    line.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
    for (u32 i = 0; i < numFrames; i++) {
        DWORD64 address = (DWORD64) stack[i];
        SymFromAddr(processHandle, address, null, symbol);

        if (SymGetLineFromAddr64(processHandle, address, &displacement, &line)) {
            if (string == null) {
                print("  %-30s %s:%u\n", symbol->Name, line.FileName, line.LineNumber);

            } else {
                string->appendf("  %-30s %s:%u\n", symbol->Name, line.FileName, line.LineNumber);
            }
        } else {
            if (string == null) {
                warn("SymGetLineFromAddr64 returned error code %lu.\n", GetLastError());
                print("  %-30s unknown file\n", symbol->Name);

            } else {
                warn("SymGetLineFromAddr64 returned error code %lu.\n", GetLastError());
                string->appendf("  %-30s unknown file\n", symbol->Name);
            }
        }
    }
    #undef BACKTRACE_MAX_FUNCTION_NAME_LENGTH
}
#include <Minidumpapiset.h>
#include <tchar.h>
void writeMinidump(void* exceptionPointers) { // 'EXCEPTION_POINTERS*' actually
    // create a file
    EXCEPTION_POINTERS* ep = (EXCEPTION_POINTERS*) exceptionPointers;
    HANDLE hFile = CreateFile(_T("MiniDump.dmp"), GENERIC_READ | GENERIC_WRITE, 0, null, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, null);

    if ((hFile != null) && (hFile != INVALID_HANDLE_VALUE)) {
        // carry on with creating the minidump
        MINIDUMP_EXCEPTION_INFORMATION mdei;
        mdei.ThreadId           = GetCurrentThreadId();
        mdei.ExceptionPointers  = ep;
        mdei.ClientPointers     = FALSE;

        MINIDUMP_TYPE mdt       = MiniDumpNormal;
        BOOL rv = MiniDumpWriteDump(GetCurrentProcess(), GetCurrentProcessId(), hFile, mdt, (ep != 0) ? &mdei : 0, 0, 0);
        if (!rv) {
            println(_T("MiniDumpWriteDump failed. Error: %u"), GetLastError());
        } else {
            println(_T("MiniDump created."));
        }

        CloseHandle(hFile);
    } else {
        println(_T("Failed to CreateFile for MiniDump. Error: %u"), GetLastError());
    }
}
#else
void writeMinidump(void* exceptionPointers) {} // stub... does nothing on Unix

// OSX and Linux stacktrace stuff.
#include <execinfo.h> // backtrace, backtrace_symbols
#include <cxxabi.h> // abi::__cxa_demangle
// if |string| is non-null, then the stack trace will be concatenated to it instead of being printed to stdout.
void trace(String* string) {
    ULE_TYPES_H_FTAG;

    void* stack[BACKTRACE_MAX_FRAMES];
    u32 stackSize = backtrace(stack, BACKTRACE_MAX_FRAMES);

    // resolve addresses into strings containing "filename(function+address)"
    // this array must be free()-ed
    char** traces = backtrace_symbols(stack, stackSize);

    // iterate over the returned symbol lines. skip the first, it is the address of this function
    for (u32 i = 1; i < stackSize; i++) {

        // the names as provided by 'backtrace_symbols' are mangled for some reason.
        // we have to demangle them, using this weird api
        // example mangled names (wrapped in double quotes):
        // "2   shard_tracy                         0x00000001032d5618 _ZL17drawSettingsPanelv + 904"
        // "2   shard                               0x000000010ed8be34 _ZN6ShaderC2EPKcS1_P5ArrayIS1_ES1_ + 1108"
        // "12  shard                               0x000000010ed5edeb main + 43"
        //
        // the rule for finding the 'first' character is annoying, because it's usually but not always starting with an underscore,
        // and when it is an underscore it's usually but not always the first underscore in the string.
        char buffer[1024];
        const char* mangledNameEnd = String::lastCharOccurence(traces[i], '+'); // it actually ends one char before.
        const char* mangledNameBegin = null;

        if (mangledNameEnd != null && ((mangledNameEnd - traces[i]) > 2)) {
            const char* cursor = mangledNameEnd - 2;
            while (cursor != traces[i]) {
                if (*cursor == '_') {
                    mangledNameBegin = cursor;

                } else if (*cursor == ' ') {
                    mangledNameBegin = cursor + 1;
                    break;
                }
                cursor--;
            }
        }

        if (mangledNameBegin == null || mangledNameEnd == null) {
            // we can't demangle this name for some reason, just copy the mangled name to the buffer
            size_t length = String::len(traces[i]);
            String::memcpy(buffer, (void*)traces[i], length);
            buffer[length] = '\0';

        } else {
            size_t length = mangledNameEnd - mangledNameBegin - 1;
            String::memcpy(buffer, (void*)mangledNameBegin, length);
            buffer[length] = '\0';
        }

        s32 status = -1;
        char* trace = abi::__cxa_demangle(buffer, null, null, &status);
        if (trace == null) {
            // @HACK, both 'main' and 'start' symbols will fail to be demangled, and we don't really care about printing them
            // in most cases. your application (certainly true for us) will have its own endpoint which itself is of questionable
            // usefulness to print, but 'main' and 'start' are even less useful.
            if (String::memeq((const unsigned char*)(mangledNameBegin), (const unsigned char*)"main", sizeof("main") - 1)) {
                continue;

            } else if (String::memeq((const unsigned char*)(mangledNameBegin), (const unsigned char*)"start", sizeof("start") - 1)) {
                continue;

            } else {
                warn("warning: failed to demangle name: %s, exit status of attempt: %d", traces[i], status);
                // just write back the original trace, un-demangled.
                trace = traces[i];
            }
        }

        if (string == null) {
            print("  %s\n", trace);

        } else {
            string->appendf("  %s\n", trace);
        }
    }

    pFree(traces);
}
#undef BACKTRACE_MAX_FRAMES
#endif

void _debug(
    const char* date,
    const char* time,
    const char* filename,
    const int line,
    const char* format,
    ...
) {
    ULE_TYPES_H_FTAG;
    if (format == null) {
        print("[%s, %s] [%s:%d] null\n", date, time, filename, line);
        return;
    }

    va_list args;
    va_start(args, format);

    print("[%s, %s] [%s:%d] ", date, time, filename, line);
    vprintln(format, args);

    va_end(args);
}

void _warn(
    const char* date,
    const char* time,
    const char* filename,
    const int line,
    const char* format,
    ...
) {
    ULE_TYPES_H_FTAG;
    if (format == null) {
        print("[%s, %s] [%s:%d] %swarning:%s null\n", date, time, filename, line, ANSI_YELLOW, ANSI_RESET);
        return;
    }

    va_list args;
    va_start(args, format);

    print("[%s, %s] [%s:%d] %swarning:%s ", date, time, filename, line, ANSI_YELLOW, ANSI_RESET);
    vprintln(format, args);

    va_end(args);
}

static void (*customDie)(const char* string) = null;
// if you want to override what happens by default when your program calls 'die', you can do so here.
// just keep in mind the intention is for 'die' to be for when your program has encountered a fatal, unrecoverable error.
void setCustomDieBehavior(void (*dieBehavior)(const char* string)) {
    customDie = dieBehavior;
}

// for fatal errors which may occur at runtime, even on a release binary.
// if a fatal error should not occur at runtime on a release binary, consider preferring 'massert'
// it's unclear when you should use asserts vs. die actually. idk man, they kinda do the same thing right now
void _die(
    const char* date,
    const char* time,
    const char* filename,
    const int line,
    const char* format,
    ...
) {
    ULE_TYPES_H_FTAG;
    if (format == null) {
        if (customDie == null) {
            print("[%s, %s] [%s:%d] %serror:%s (unspecified error)", date, time, filename, line, ANSI_RED, ANSI_RESET);
            trace();
            exit(1);
            return;

        } else {
            String string = String128f("error: (unspecified error)\n");
            trace(&string);
            customDie(string.c_str());
            return;
        }
    }

    va_list args;
    va_start(args, format);

    if (customDie == null) {
        println("[%s, %s] [%s:%d] %serror:%s ", date, time, filename, line, ANSI_RED, ANSI_RESET);
        vprintln(format, args);
        println();

        va_end(args);

        trace();
        exit(1);

    } else {
        String string = String128f("");
        string.appendfv(format, args);
        string.append("\n");
        trace(&string);

        va_end(args);

        customDie(string.c_str());
    }
}

void print(bool b)         { ULE_TYPES_H_FTAG; print("%s", b ? "true" : "false"); }
void print(char c)         { ULE_TYPES_H_FTAG; print("%c", c); }
void print(signed int i)   { ULE_TYPES_H_FTAG; print("%d", i); }
void print(unsigned int i) { ULE_TYPES_H_FTAG; print("%u", i); }
void print(float f)        { ULE_TYPES_H_FTAG; print("%.14g", f); }
void print(double d)       { ULE_TYPES_H_FTAG; print("%.14g", d); }
void print(void* p)        { ULE_TYPES_H_FTAG; print("%p", p); }
void print(char* s)        { ULE_TYPES_H_FTAG; print("%s", s); }

#ifndef _WIN32
void print(size_t i) { ULE_TYPES_H_FTAG; print("%u", i); }
void println(size_t i) { ULE_TYPES_H_FTAG; print(i); print("\n"); }
#endif

void println(bool b)         { ULE_TYPES_H_FTAG; print(b); print("\n"); }
void println(char c)         { ULE_TYPES_H_FTAG; print(c); print("\n"); }
void println(signed int i)   { ULE_TYPES_H_FTAG; print(i); print("\n"); }
void println(unsigned int i) { ULE_TYPES_H_FTAG; print(i); print("\n"); }
void println(float f)        { ULE_TYPES_H_FTAG; print(f); print("\n"); }
void println(double d)       { ULE_TYPES_H_FTAG; print(d); print("\n"); }
void println(void* p)        { ULE_TYPES_H_FTAG; print(p); print("\n"); }
void println(char* s)        { ULE_TYPES_H_FTAG; print(s); print("\n"); }
void println()               { ULE_TYPES_H_FTAG;           print("\n"); }

#ifdef ULE_CONFIG_OPTION_USE_GLM
void print(glm::vec<2, float, (glm::qualifier) 3> v)      { ULE_TYPES_H_FTAG; print("vec2: %.14g,%.14g", v.x, v.y); }
void print(glm::vec<3, float, (glm::qualifier) 3> v)      { ULE_TYPES_H_FTAG; print("vec3: %.14g,%.14g,%.14g", v.x, v.y, v.z); }
void print(glm::vec<4, float, (glm::qualifier) 3> v)      { ULE_TYPES_H_FTAG; print("vec4: %.14g,%.14g,%.14g,%.14g", v.x, v.y, v.z, v.w); }
void print(glm::mat<2, 2, float, (glm::qualifier) 3> m)   { ULE_TYPES_H_FTAG; print("mat2: "); print(m[0]); print(m[1]); }
void print(glm::mat<3, 3, float, (glm::qualifier) 3> m)   { ULE_TYPES_H_FTAG; print("mat3: "); print(m[0]); print(m[1]); print(m[2]); }
void print(glm::mat<4, 4, float, (glm::qualifier) 3> m)   { ULE_TYPES_H_FTAG; print("mat4: "); print(m[0]); print(m[1]); print(m[2]); print(m[3]); }

void println(glm::vec<2, float, (glm::qualifier) 3> v)    { ULE_TYPES_H_FTAG; print(v); print("\n"); }
void println(glm::vec<3, float, (glm::qualifier) 3> v)    { ULE_TYPES_H_FTAG; print(v); print("\n"); }
void println(glm::vec<4, float, (glm::qualifier) 3> v)    { ULE_TYPES_H_FTAG; print(v); print("\n"); }
void println(glm::mat<2, 2, float, (glm::qualifier) 3> m) { ULE_TYPES_H_FTAG; print(m); print("\n"); }
void println(glm::mat<3, 3, float, (glm::qualifier) 3> m) { ULE_TYPES_H_FTAG; print(m); print("\n"); }
void println(glm::mat<4, 4, float, (glm::qualifier) 3> m) { ULE_TYPES_H_FTAG; print(m); print("\n"); }
#endif // ULE_CONFIG_OPTION_USE_GLM