// posix_path.c - POSIX <-> native path translation
#include <stddef.h>
#include <string.h>
#include "posix_path.h"

// The drive letter used as the POSIX filesystem root.
// A future SYS_GET_BOOT_DRIVE could populate this; hardcoded for v1.
static const char gRootDrive = 'C';

static void FlipSlashes(char* s) {
    for (; *s; s++) if (*s == '/') *s = '\\';
}

const char* PosixTranslatePath(const char* in, char* out, size_t outSize) {
    if (!in || !out || outSize < 4) return out;

    // Synthetic devices
    if (strcmp(in, "/dev/null") == 0) return SYNTH_DEVNULL;
    if (strcmp(in, "/dev/zero") == 0) return SYNTH_DEVZERO;

    // /proc/self/* - read-only synthesized files; flag with a sentinel so
    // posix_io.c can intercept them without opening a real file.
    // (In v1 only /proc/self/pid is handled; others fall through to ENOENT.)

    if (in[0] == '/') {
        // Absolute POSIX path -> C:\...
        // outSize must fit "C:\" + rest
        out[0] = gRootDrive;
        out[1] = ':';
        out[2] = '\\';
        size_t rest = strlen(in + 1);
        if (rest + 4 > outSize) rest = outSize - 4;
        memcpy(out + 3, in + 1, rest);
        out[3 + rest] = '\0';
    } else {
        // Relative - pass through with slash flip only
        size_t len = strlen(in);
        if (len + 1 > outSize) len = outSize - 1;
        memcpy(out, in, len);
        out[len] = '\0';
    }

    FlipSlashes(out);
    return out;
}

void NativeToPosix(const char* in, char* out, size_t outSize) {
    if (!in || !out || outSize == 0) return;

    // Strip "X:\" prefix if present
    const char* src = in;
    if (src[0] != '\0' && src[1] == ':' && (src[2] == '\\' || src[2] == '/'))
        src += 2;   // skip "C:", leave the leading backslash

    size_t len = strlen(src);
    if (len + 1 > outSize) len = outSize - 1;
    memcpy(out, src, len);
    out[len] = '\0';

    // Backslash -> forward slash
    for (char* p = out; *p; p++) if (*p == '\\') *p = '/';
}