#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdarg.h>
#include <string.h>
#include <uchar.h>
#include <err.h>

#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

static char *ascii(const char16_t *wstr, bool translate_slashes)
{
    size_t len = 0;
    for (const char16_t *wp = wstr; *wp; wp++)
        len++;
    char *ret = malloc(len + 1);
    char *p = ret;
    for (const char16_t *wp = wstr; *wp; wp++)
        *p++ = (*wp == '\\' && translate_slashes ? '/' :
                *wp < 0x80 ? *wp :
                '?');
    *p = '\0';
    return ret;
}

static void system_argv(const char *cmd, ...)
{
    int nargs, nchars;
    const char *word;
    va_list ap;

    va_start(ap, cmd);
    nargs = 1;                         /* terminating NULL */
    nchars = 0;
    for (word = cmd; word; word = va_arg(ap, const char *)) {
        nargs++;
        nchars += 1 + strlen(word);
    }
    va_end(ap);

    char *args[nargs], chars[nchars];
    char **argp = args, *charp = chars;
    va_start(ap, cmd);
    for (word = cmd; word; word = va_arg(ap, const char *)) {
        *argp++ = charp;
        strcpy(charp, word);
        charp += 1 + strlen(word);
    }
    va_end(ap);
    *argp++ = NULL;

    pid_t pid = fork();
    if (pid < 0)
        err(1, "fork");

    if (pid == 0) {
        execvp(args[0], args);
        warn("execvp");
        _exit(127);
    }

    int status;
    if (waitpid(pid, &status, 0) != pid)
        err(1, "waitpid");
    if (!(WIFEXITED(status) && WEXITSTATUS(status) == 0))
        errx(1, "subcommand failed");
}

uint32_t HashPublicKeyInfo(void *pCertContext,
                           void *rgbSubjectKeyIdentifier,
                           uint32_t *pcbSubjectKeyIndentifier)
{
    errx(1, "HashPublicKeyInfo NYI");
}

uint32_t ResetAcls(const char16_t **pwzFiles, uint32_t cFiles)
{
    return 0;
}

uint32_t CreateCabBegin(const char16_t *wzCab, const char16_t *wzCabDir,
                        uint32_t dwMaxFiles, uint32_t dwMaxSize,
                        uint32_t dwMaxThresh, int compression,
                        void **out_ctx)
{
    fprintf(stderr, "CreateCabBegin(\"%s\", \"%s\", ...)!\n",
            ascii(wzCab, true), ascii(wzCabDir, true));
    return 0;
}

uint32_t CreateCabAddFile(const char16_t *wzFile, const char16_t *wzToken,
                          void *pmfHash, void *ctx)
{
    fprintf(stderr, "CreateCabAddFile!\n");
    return 0;
}

uint32_t CreateCabAddFiles(const char16_t *const *pwzFiles,
                           const char16_t *const *pwzTokens,
                           void *pmfHash, uint32_t cFiles, void *hContext)
{
    fprintf(stderr, "CreateCabAddFiles!\n");
    return 0;
}

uint32_t CreateCabFinish(void *hContext, void *newCabNamesCallBackAddress)
{
    /* FIXME: newCabNamesCallBackAddress is actually a fn ptr of some kind */
    fprintf(stderr, "CabCFinish(%p,%p)!\n",
            hContext, newCabNamesCallBackAddress);
    return 0;
}

void CreateCabCancel(void *hContext)
{
    fprintf(stderr, "CabCCancel(%p)!\n", hContext);
}

uint32_t ExtractCabBegin(void)
{
    return 0;
}

uint32_t ExtractCab(const char16_t *wzCabinet, const char16_t *wzExtractDir)
{
    char *cab = ascii(wzCabinet, true), *dir = ascii(wzExtractDir, true);
    fprintf(stderr, "ExtractCab(\"%s\", \"%s\"\n", cab, dir);
    system_argv("cabextract", "-d", dir, cab, (const char *)NULL);
    return 0;
}

void ExtractCabFinish(void)
{
}

uint32_t EnumerateCabBegin(void)
{
    return 0;
}

uint32_t EnumerateCab(const char16_t *wzCabinet, void *pfnNotify)
{
    /* FIXME: fpnNotify looks like a fn ptr again */
    fprintf(stderr, "EnumerateCab!\n");
    return 0;
}

void EnumerateCabFinish(void)
{
}