/*
 * This merges the file listing in the directory cache index
 * with the actual working directory list, and shows different
 * combinations of the two.
 *
 * Copyright (C) Linus Torvalds, 2005
 */
#include <dirent.h>
#include <fnmatch.h>

#include "cache.h"

static int show_deleted = 0;
static int show_cached = 0;
static int show_others = 0;
static int show_ignored = 0;
static int show_stage = 0;
static int show_unmerged = 0;
static int line_terminator = '\n';

static int nr_excludes;
static const char **excludes;
static int excludes_alloc;

static void add_exclude(const char *string)
{
        if (nr_excludes == excludes_alloc) {
                excludes_alloc = alloc_nr(excludes_alloc);
                excludes = realloc(excludes, excludes_alloc*sizeof(char *));
        }
        excludes[nr_excludes++] = string;
}

static void add_excludes_from_file(const char *fname)
{
        int fd, i;
        long size;
        char *buf, *entry;

        fd = open(fname, O_RDONLY);
        if (fd < 0)
                goto err;
        size = lseek(fd, 0, SEEK_END);
        if (size < 0)
                goto err;
        lseek(fd, 0, SEEK_SET);
        if (size == 0) {
                close(fd);
                return;
        }
        buf = xmalloc(size);
        if (read(fd, buf, size) != size)
                goto err;
        close(fd);

        entry = buf;
        for (i = 0; i < size; i++) {
                if (buf[i] == '\n') {
                        if (entry != buf + i) {
                                buf[i] = 0;
                                add_exclude(entry);
                        }
                        entry = buf + i + 1;
                }
        }
        return;

err:    perror(fname);
        exit(1);
}

static int excluded(const char *pathname)
{
        int i;
        if (nr_excludes) {
                const char *basename = strrchr(pathname, '/');
                basename = (basename) ? basename+1 : pathname;
                for (i = 0; i < nr_excludes; i++)
                        if (fnmatch(excludes[i], basename, 0) == 0)
                                return 1;
        }
        return 0;
}

static const char **dir;
static int nr_dir;
static int dir_alloc;

static void add_name(const char *pathname, int len)
{
        char *name;

        if (cache_name_pos(pathname, len) >= 0)
                return;

        if (nr_dir == dir_alloc) {
                dir_alloc = alloc_nr(dir_alloc);
                dir = xrealloc(dir, dir_alloc*sizeof(char *));
        }
        name = xmalloc(len + 1);
        memcpy(name, pathname, len + 1);
        dir[nr_dir++] = name;
}

/*
 * Read a directory tree. We currently ignore anything but
 * directories and regular files. That's because git doesn't
 * handle them at all yet. Maybe that will change some day.
 *
 * Also, we currently ignore all names starting with a dot.
 * That likely will not change.
 */
static void read_directory(const char *path, const char *base, int baselen)
{
        DIR *dir = opendir(path);

        if (dir) {
                struct dirent *de;
                char fullname[MAXPATHLEN + 1];
                memcpy(fullname, base, baselen);

                while ((de = readdir(dir)) != NULL) {
                        int len;

                        if (de->d_name[0] == '.')
                                continue;
                        if (excluded(de->d_name) != show_ignored)
                                continue;
                        len = strlen(de->d_name);
                        memcpy(fullname + baselen, de->d_name, len+1);

                        switch (DTYPE(de)) {
                        struct stat st;
                        default:
                                continue;
                        case DT_UNKNOWN:
                                if (lstat(fullname, &st))
                                        continue;
                                if (S_ISREG(st.st_mode))
                                        break;
                                if (!S_ISDIR(st.st_mode))
                                        continue;
                                /* fallthrough */
                        case DT_DIR:
                                memcpy(fullname + baselen + len, "/", 2);
                                read_directory(fullname, fullname, baselen + len + 1);
                                continue;
                        case DT_REG:
                                break;
                        }
                        add_name(fullname, baselen + len);
                }
                closedir(dir);
        }
}

static int cmp_name(const void *p1, const void *p2)
{
        const char *n1 = *(const char **)p1;
        const char *n2 = *(const char **)p2;
        int l1 = strlen(n1), l2 = strlen(n2);

        return cache_name_compare(n1, l1, n2, l2);
}

static void show_files(void)
{
        int i;

        /* For cached/deleted files we don't need to even do the readdir */
        if (show_others) {
                read_directory(".", "", 0);
                qsort(dir, nr_dir, sizeof(char *), cmp_name);
                for (i = 0; i < nr_dir; i++)
                        printf("%s%c", dir[i], line_terminator);
        }
        if (show_cached | show_stage) {
                for (i = 0; i < active_nr; i++) {
                        struct cache_entry *ce = active_cache[i];
                        if (excluded(ce->name) != show_ignored)
                                continue;
                        if (show_unmerged && !ce_stage(ce))
                                continue;
                        if (!show_stage)
                                printf("%s%c", ce->name, line_terminator);
                        else
                                printf(/* "%06o %s %d %10d %s%c", */
                                       "%06o %s %d %s%c",
                                       ntohl(ce->ce_mode),
                                       sha1_to_hex(ce->sha1),
                                       ce_stage(ce),
                                       /* ntohl(ce->ce_size), */
                                       ce->name, line_terminator); 
                }
        }
        if (show_deleted) {
                for (i = 0; i < active_nr; i++) {
                        struct cache_entry *ce = active_cache[i];
                        struct stat st;
                        if (excluded(ce->name) != show_ignored)
                                continue;
                        if (!stat(ce->name, &st))
                                continue;
                        printf("%s%c", ce->name, line_terminator);
                }
        }
}

static const char *ls_files_usage =
        "ls-files [-z] (--[cached|deleted|others|stage|unmerged])* "
        "[ --ignored [--exclude=<pattern>] [--exclude-from=<file>) ]";

int main(int argc, char **argv)
{
        int i;

        for (i = 1; i < argc; i++) {
                char *arg = argv[i];

                if (!strcmp(arg, "-z")) {
                        line_terminator = 0;
                } else if (!strcmp(arg, "-c") || !strcmp(arg, "--cached")) {
                        show_cached = 1;
                } else if (!strcmp(arg, "-d") || !strcmp(arg, "--deleted")) {
                        show_deleted = 1;
                } else if (!strcmp(arg, "-o") || !strcmp(arg, "--others")) {
                        show_others = 1;
                } else if (!strcmp(arg, "-i") || !strcmp(arg, "--ignored")) {
                        show_ignored = 1;
                } else if (!strcmp(arg, "-s") || !strcmp(arg, "--stage")) {
                        show_stage = 1;
                } else if (!strcmp(arg, "-u") || !strcmp(arg, "--unmerged")) {
                        // There's no point in showing unmerged unless you also show the stage information
                        show_stage = 1;
                        show_unmerged = 1;
                } else if (!strcmp(arg, "-x") && i+1 < argc) {
                        add_exclude(argv[++i]);
                } else if (!strncmp(arg, "--exclude=", 10)) {
                        add_exclude(arg+10);
                } else if (!strcmp(arg, "-X") && i+1 < argc) {
                        add_excludes_from_file(argv[++i]);
                } else if (!strncmp(arg, "--exclude-from=", 15)) {
                        add_excludes_from_file(arg+15);
                } else
                        usage(ls_files_usage);
        }

        if (show_ignored && !nr_excludes) {
                fprintf(stderr, "%s: --ignored needs some exclude pattern\n", argv[0]);
                exit(1);
        }

        /* With no flags, we default to showing the cached files */
        if (!(show_stage | show_deleted | show_others | show_unmerged))
                show_cached = 1;

        read_cache();
        show_files();
        return 0;
}