#include "scripting.h"

void handle_tcc_error(void* opaque, const char* msg)
{
    TraceLog(LOG_ERROR, msg);
}

void initScripting(SldjScripting* scripting)
{
    *scripting = (SldjScripting){
        .state = NULL,
        .lineScanner = NULL,
        .loadContext = NULL,
        .fileBuf = NULL,
        .fileSize = 0
    };
}

void compileScript(SldjScripting* scripting, const char filePath[SLDJ_NAMEMAX])
{
    scripting->lineScanner = NULL;
    scripting->loadContext = NULL;
    
    // Get file size.
    struct stat fileState;

    if (stat(filePath, &fileState) < 0)
    {
        TraceLog(LOG_ERROR, strerror(errno));
        return;
    }

    scripting->fileSize = fileState.st_size;

    // Load file information into a buffer.
    if (scripting->fileBuf == NULL)
    {
        scripting->fileBuf = (char*)malloc(scripting->fileSize);
    } else {
        scripting->fileBuf = (char*)realloc(scripting->fileBuf, scripting->fileSize);
    }

    if (scripting->fileBuf == NULL)
    {
        TraceLog(LOG_ERROR, strerror(errno));
        return;
    }

    FILE* file = fopen(filePath, "r");

    if (file == NULL)
    {
        TraceLog(LOG_ERROR, strerror(errno));
        return;
    }

    fread(scripting->fileBuf, scripting->fileSize, 1, file);
    scripting->fileBuf[scripting->fileSize - 1] = '\0';
    fclose(file);

    // Setup compiler.
    if (scripting->state != NULL)
    {
        tcc_delete(scripting->state);
    }

    scripting->state = tcc_new();
    
    if (scripting->state == NULL)
    {
        TraceLog(LOG_ERROR, "Could not open tcc state");
        return;
    }

    tcc_set_error_func(scripting->state, stderr, handle_tcc_error);
    tcc_set_output_type(scripting->state, TCC_OUTPUT_MEMORY);

    tcc_add_library_path(scripting->state, "./");
    tcc_add_library(scripting->state, "libsldj");

    // Compile.
    if (tcc_compile_string(scripting->state, scripting->fileBuf) < 0)
    {
        return;
    }

    if (tcc_relocate(scripting->state) < 0)
    {
        return;
    }

    scripting->lineScanner = tcc_get_symbol(scripting->state, "lineScanner");
    scripting->loadContext = tcc_get_symbol(scripting->state, "loadContext");
}

void closeScripting(SldjScripting* scripting)
{
    if (scripting->state != NULL)
    {
        tcc_delete(scripting->state);
    }

    if (scripting->fileBuf != NULL)
    {
        free(scripting->fileBuf);
    }
}