#include <stdio.h>
#include <string.h>
#include "instruktion.c"
#include "code.c"
#include "stack.c"
#include "program.c"
#include "codeReader.c"
#include "SDA.c"

// Program
struct program *program;

// SDA
unsigned fp;

void version(void) {
    printf("Ninja Virtual Machine version %i (compiled %s, %s)\n", 0, __DATE__, __TIME__);
}

void help(void) {
    printf("Usage: ./njvm [options] <code file>\n\t--debug\tstart virtual machine in debug mode\n\t--version\tshow version and exit\n\t--help\t\tshow this help and exit\n");
}

void execute(struct program *program, struct sda *sda) {
    struct stack stack;
    stack.size = 1000;
    stack.currentFrame = 0;

    for (int i = 0; i < stack.size; ++i) {
        struct stackFrame *frame = malloc(sizeof(struct stackFrame));
        frame->fp = malloc(sizeof(unsigned int) * stack.size);
        frame->sp = malloc(sizeof(unsigned int) * stack.size);
        frame->bp = NULL;
        stack.frames[i] = frame;
    }

    struct stackFrame *currentFrame = NULL;
    unsigned int tmp;
    int intInput;
    char charInput;

    for (int i = 0; i < program->size; ++i) {
        unsigned int instruction = program->program[i];
        switch (instruction >> 24) {
            case HALT:
                goto end;
            case PUSHC:
                push(&stack, SIGN_EXTEND(IMMEDIATE(instruction)));
                break;
            case ADD:
                push(&stack, pop(&stack) + pop(&stack));
                break;
            case SUB:
                tmp = pop(&stack);
                push(&stack, pop(&stack) - tmp);
                break;
            case MUL:
                push(&stack, pop(&stack) * pop(&stack));
                break;
            case DIV:
                tmp = pop(&stack);
                push(&stack, pop(&stack) / tmp);
                break;
            case MOD:
                tmp = pop(&stack);
                push(&stack, pop(&stack) % tmp);
                break;
            case RDINT:
                scanf("%i", &intInput);
                push(&stack, intInput);
                break;
            case WRINT:
                printf("%i", pop(&stack));
                break;
            case RDCHR:
                scanf("%c", &charInput);
                push(&stack, charInput);
                break;
            case WRCHR:
                printf("%c", pop(&stack));
                break;
            case PUSHG:
                currentFrame = stack.frames[stack.currentFrame];
                currentFrame->bp = currentFrame->sp;

                *currentFrame->sp++ = getSDA(SIGN_EXTEND(IMMEDIATE(instruction)), sda);
                break;
            case POPG:
                currentFrame = stack.frames[stack.currentFrame];
                currentFrame->bp = currentFrame->sp;

                setSDA(SIGN_EXTEND(IMMEDIATE(instruction)), pop(&stack), sda);
                break;
            case ASF:
                currentFrame = stack.frames[stack.currentFrame];
                push(&stack, *currentFrame->sp);
                *currentFrame->sp = stack.currentFrame;
                currentFrame->bp = currentFrame->sp;

                stack.currentFrame += SIGN_EXTEND(IMMEDIATE(instruction));
                break;
            case RSF:
                stack.currentFrame = pop(&stack);
                currentFrame = stack.frames[stack.currentFrame];
                currentFrame->bp = NULL;
                break;
            case PUSHL:
                currentFrame = stack.frames[stack.currentFrame];
                push(&stack, currentFrame->fp[SIGN_EXTEND(IMMEDIATE(instruction))]);
                break;
            case POPL:
                currentFrame = stack.frames[stack.currentFrame];
                currentFrame->fp[SIGN_EXTEND(IMMEDIATE(instruction))] = pop(&stack);
                break;
        }
    }

    end:
    return;
}

// run prog2.bin
void tests(void) {
    printf("Test started\n");
    struct sda *sda = malloc(sizeof(struct sda));
    unsigned int s[1000];
    sda->size = 1000;
    sda->sda = s;
    fromFile("prog2.bin", program);
    execute(program, (struct sda *) &sda);
    printf("Test finished\n");
}

int main(int argc, char *argv[]) {
    // Initialize the Stack
    struct stack stack;
    int size = SIZE;
    stack.size = size;
    stack.currentFrame = 0;

    // Initialize ProgrammSpeicher
    int psize = SIZE;
    unsigned int p[1000];
    program = malloc(sizeof(struct program));
    program->size = psize;
    program->program = p;

    // Initialize runtime variables
    int debug = 0;
    int run = 0;
    int sizeSDA;

    if (argc > 1) {
        for (int i = 1; i < argc; ++i) {
            if (strcmp(argv[i], "--debug") == 0) {
                debug = 1;
            } else if (strcmp(argv[i], "--version") == 0) {
                version();
                return 0;
            } else if (strcmp(argv[i], "--help") == 0) {
                help();
                return 0;
            } else {
                sizeSDA = fromFile(argv[i], program);
                run = 1;
            }
        }
    }

    /*
     * Debug mode
     */
    if (debug) {
        tests();
    }

    /*
     * Run program
     */
    if (run) {
        printf("Ninja Virtual Machine started\n");
        struct sda *sda = malloc(sizeof(struct sda));
        unsigned int s[sizeSDA];
        sda->size = sizeSDA;
        sda->sda = s;
        printProgram(program);
        execute(program, (struct sda *) &sda);
        if (debug == 1) printSDA(sda);
        printf("Ninja Virtual Machine stopped\n");
    } else {
        printf("Error: no code file specified\n");
        return 1;
    }
    return 0;
}