/*
 * Copyright 2008-2009, Axel Dörfler, axeld@pinc-software.de.
 * Distributed under the terms of the MIT License.
 */


#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include <OS.h>


extern const char* __progname;
const char* kProgramName = __progname;

const int32_t kDefaultFiles = -1;
const off_t kDefaultFileSize = 4096;


static void
usage(int status)
{
        printf("usage: %s [--files <num-of-files>] [--size <file-size>]\n",
                kProgramName);
        printf("options:\n");
        printf("  -f  --files  Number of files to be created. Defaults to as "
                "many as fit.\n");
        printf("  -s  --size   Size of each file. Defaults to %lldKB.\n",
                kDefaultFileSize / 1024);

        exit(status);
}


static bool
create_file(int32_t i, const char* suffix, const char* buffer, size_t size)
{
        char name[64];
        snprintf(name, sizeof(name), "fragments/%06d%s", i, suffix);

        int fd = open(name, O_CREAT | O_WRONLY | O_TRUNC, 0644);
        if (fd < 0) {
                fprintf(stderr, "%s: Could not create file %d: %s\n", kProgramName,
                        i, strerror(errno));
                return false;
        }

        if (write(fd, buffer, size) < (ssize_t)size) {
                fprintf(stderr, "%s: Could not write file %d: %s\n", kProgramName,
                        i, strerror(errno));
                return false;
        }

        close(fd);
        return true;
}


int
main(int argc, char** argv)
{
        int32_t numFiles = kDefaultFiles;
        off_t fileSize = kDefaultFileSize;

        int optionIndex = 0;
        int opt;
        static struct option longOptions[] = {
                {"help", no_argument, 0, 'h'},
                {"size", required_argument, 0, 's'},
                {"files", required_argument, 0, 'f'},
                {0, 0, 0, 0}
        };

        do {
                opt = getopt_long(argc, argv, "hs:f:", longOptions, &optionIndex);
                switch (opt) {
                        case -1:
                                // end of arguments, do nothing
                                break;

                        case 'f':
                                numFiles = strtoul(optarg, NULL, 0);
                                break;

                        case 's':
                                fileSize = strtoul(optarg, NULL, 0);
                                break;

                        case 'h':
                        default:
                                usage(0);
                                break;
                }
        } while (opt != -1);

        // fill buffer

        char* buffer = (char*)malloc(fileSize);
        if (buffer == NULL) {
                fprintf(stderr, "%s: not enough memory.\n", kProgramName);
                exit(1);
        }

        for (uint32_t i = 0; i < fileSize; i++) {
                buffer[i] = (char)(i & 0xff);
        }

        // create files

        if (numFiles > 0)
                printf("Creating %d files...\n", numFiles);
        else
                printf("Creating as many files as fit...\n");

        mkdir("fragments", 0777);

        int32_t filesCreated = 0;
        bigtime_t lastTime = 0;

        for (int32_t i = 0; i < numFiles || numFiles < 0; i++) {
                if (!create_file(i, "", buffer, fileSize)
                        || !create_file(i, ".remove", buffer, fileSize))
                        break;

                filesCreated++;

                if (lastTime + 250000LL < system_time()) {
                        printf("%10d\33[1A\n", filesCreated);
                        lastTime = system_time();
                }
        }

        free(buffer);

        // delete fragmentation files

        printf("Deleting %d temporary files...\n", filesCreated);

        for (int32_t i = 0; i < filesCreated; i++) {
                char name[64];
                snprintf(name, sizeof(name), "fragments/%06d.remove", i);

                if (remove(name) != 0) {
                        fprintf(stderr, "%s: Could not remove file %d: %s\n",
                                kProgramName, i, strerror(errno));
                }

                if (lastTime + 250000LL < system_time()) {
                        printf("%10d\33[1A\n", i);
                        lastTime = system_time();
                }
        }

        printf("          \33[1A\n");
                // delete progress count

        return 0;
}