/*
 * CS5600 University of Utah
 * Charles McGarvey
 * mcgarvey@eng.utah.edu
 */

#define _POSIX_C_SOURCE 2
#include <errno.h>
#include <unistd.h>

#include "raster.h"
#include "scene.h"


/*
 * Load a scene from a file.
 */
static int load(scene_t** scene, const char* filename)
{
    FILE* file = fopen(filename, "r");
    if (file == NULL) {
        fprintf(stderr, "Cannot read %s: %s\n", filename, strerror(errno));
        return -1;
    }

    *scene = scene_alloc(file);
    if (*scene == NULL) {
        fclose(file);
        return -1;
    }

    fclose(file);
    return 0;
}

/*
 * Load a scene from standard input.
 */
static int load_from_stdin(scene_t** scene)
{
    *scene = scene_alloc(stdin);
    if (*scene == NULL) {
        return -1;
    }
    return 0;
}

/*
 * Load a scene file, render it, and export it.
 */
static void draw(const char* filename)
{
    scene_t* scene;
    TRY_DO("Loading %s", load(&scene, filename), filename);

    raster_t* raster = scene_render(scene);
    scene_destroy(scene);
    raster_printstats(raster);

    char* u3d = mem_strdup(filename);
    strcut(u3d, '.');
#if EXPORT_PPM
    char* ppm = mem_strcat(u3d, ".ppm");
    TRY_DO("Exporting to %s", raster_export_ppm(raster, ppm), ppm);
    mem_free(ppm);
#endif
#if EXPORT_BMP
    char* bmp = mem_strcat(u3d, ".bmp");
    TRY_DO("Exporting to %s", raster_export_bmp(raster, bmp), bmp);
    mem_free(bmp);
#endif

    mem_free(u3d);
    raster_destroy(raster);
}

/*
 * Render a scene that is read from standard input, and export to BMP.
 */
static void draw_from_stdin(const char* filename)
{
    scene_t* scene;
    TRY_DO("Loading from stdin", load_from_stdin(&scene));

    raster_t* raster = scene_render(scene);
    scene_destroy(scene);
    raster_printstats(raster);

    TRY_DO("Exporting to %s", raster_export_bmp(raster, filename), filename);

    raster_destroy(raster);
}

/*
 * Render one or more scenes from 3D scene files.
 */
int main(int argc, char* argv[])
{
    int out = 0;
    int c;
    while ((c = getopt(argc, argv, "o:")) != -1) {
        switch (c) {
        case 'o':
            ++out;
            draw_from_stdin(optarg);
        }
    }

    if (out == 0 && argc <= 1) {
        draw("scene.u3d");
    }
    else {
        for (int i = optind; i < argc; ++i) {
            draw(argv[i]);
        }
    }

#if !NDEBUG
    int _blocks = mem_blocks();
    if (_blocks != 0) {
        fprintf(stderr, " *** Leaked %d blocks of memory! ***\n", _blocks);
        return EXIT_FAILURE;
    }
#endif
    return EXIT_SUCCESS;
}