/*
 * "git add" builtin command
 *
 * Copyright (C) 2006 Linus Torvalds
 */
#include "cache.h"
#include "builtin.h"
#include "dir.h"
#include "exec_cmd.h"
#include "cache-tree.h"
#include "diff.h"
#include "diffcore.h"
#include "commit.h"
#include "revision.h"

static const char builtin_add_usage[] =
"git-add [-n] [-v] [-f] [--interactive | -i] [-u] [--] <filepattern>...";

static int take_worktree_changes;
static const char *excludes_file;

static void prune_directory(struct dir_struct *dir, const char **pathspec, int prefix)
{
        char *seen;
        int i, specs;
        struct dir_entry **src, **dst;

        for (specs = 0; pathspec[specs];  specs++)
                /* nothing */;
        seen = xcalloc(specs, 1);

        src = dst = dir->entries;
        i = dir->nr;
        while (--i >= 0) {
                struct dir_entry *entry = *src++;
                if (match_pathspec(pathspec, entry->name, entry->len,
                                   prefix, seen))
                        *dst++ = entry;
        }
        dir->nr = dst - dir->entries;

        for (i = 0; i < specs; i++) {
                if (!seen[i] && !file_exists(pathspec[i]))
                        die("pathspec '%s' did not match any files",
                                        pathspec[i]);
        }
}

static void fill_directory(struct dir_struct *dir, const char **pathspec,
                int ignored_too)
{
        const char *path, *base;
        int baselen;

        /* Set up the default git porcelain excludes */
        memset(dir, 0, sizeof(*dir));
        if (!ignored_too) {
                dir->collect_ignored = 1;
                dir->exclude_per_dir = ".gitignore";
                path = git_path("info/exclude");
                if (!access(path, R_OK))
                        add_excludes_from_file(dir, path);
                if (!access(excludes_file, R_OK))
                        add_excludes_from_file(dir, excludes_file);
        }

        /*
         * Calculate common prefix for the pathspec, and
         * use that to optimize the directory walk
         */
        baselen = common_prefix(pathspec);
        path = ".";
        base = "";
        if (baselen) {
                char *common = xmalloc(baselen + 1);
                memcpy(common, *pathspec, baselen);
                common[baselen] = 0;
                path = base = common;
        }

        /* Read the directory and prune it */
        read_directory(dir, path, base, baselen, pathspec);
        if (pathspec)
                prune_directory(dir, pathspec, baselen);
}

static void update_callback(struct diff_queue_struct *q,
                            struct diff_options *opt, void *cbdata)
{
        int i, verbose;

        verbose = *((int *)cbdata);
        for (i = 0; i < q->nr; i++) {
                struct diff_filepair *p = q->queue[i];
                const char *path = p->one->path;
                switch (p->status) {
                default:
                        die("unexpacted diff status %c", p->status);
                case DIFF_STATUS_UNMERGED:
                case DIFF_STATUS_MODIFIED:
                        add_file_to_cache(path, verbose);
                        break;
                case DIFF_STATUS_DELETED:
                        remove_file_from_cache(path);
                        if (verbose)
                                printf("remove '%s'\n", path);
                        break;
                }
        }
}

static void update(int verbose, const char **files)
{
        struct rev_info rev;
        init_revisions(&rev, "");
        setup_revisions(0, NULL, &rev, NULL);
        rev.prune_data = get_pathspec(rev.prefix, files);
        rev.diffopt.output_format = DIFF_FORMAT_CALLBACK;
        rev.diffopt.format_callback = update_callback;
        rev.diffopt.format_callback_data = &verbose;
        if (read_cache() < 0)
                die("index file corrupt");
        run_diff_files(&rev, 0);
}

static int git_add_config(const char *var, const char *value)
{
        if (!strcmp(var, "core.excludesfile")) {
                if (!value)
                        die("core.excludesfile without value");
                excludes_file = xstrdup(value);
                return 0;
        }

        return git_default_config(var, value);
}

static struct lock_file lock_file;

static const char ignore_warning[] =
"The following paths are ignored by one of your .gitignore files:\n";

int cmd_add(int argc, const char **argv, const char *prefix)
{
        int i, newfd;
        int verbose = 0, show_only = 0, ignored_too = 0;
        const char **pathspec;
        struct dir_struct dir;
        int add_interactive = 0;

        for (i = 1; i < argc; i++) {
                if (!strcmp("--interactive", argv[i]) ||
                    !strcmp("-i", argv[i]))
                        add_interactive++;
        }
        if (add_interactive) {
                const char *args[] = { "add--interactive", NULL };

                if (add_interactive != 1 || argc != 2)
                        die("add --interactive does not take any parameters");
                execv_git_cmd(args);
                exit(1);
        }

        git_config(git_add_config);

        newfd = hold_locked_index(&lock_file, 1);

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

                if (arg[0] != '-')
                        break;
                if (!strcmp(arg, "--")) {
                        i++;
                        break;
                }
                if (!strcmp(arg, "-n")) {
                        show_only = 1;
                        continue;
                }
                if (!strcmp(arg, "-f")) {
                        ignored_too = 1;
                        continue;
                }
                if (!strcmp(arg, "-v")) {
                        verbose = 1;
                        continue;
                }
                if (!strcmp(arg, "-u")) {
                        take_worktree_changes = 1;
                        continue;
                }
                usage(builtin_add_usage);
        }

        if (take_worktree_changes) {
                update(verbose, argv + i);
                goto finish;
        }

        if (argc <= i) {
                fprintf(stderr, "Nothing specified, nothing added.\n");
                fprintf(stderr, "Maybe you wanted to say 'git add .'?\n");
                return 0;
        }
        pathspec = get_pathspec(prefix, argv + i);

        fill_directory(&dir, pathspec, ignored_too);

        if (show_only) {
                const char *sep = "", *eof = "";
                for (i = 0; i < dir.nr; i++) {
                        printf("%s%s", sep, dir.entries[i]->name);
                        sep = " ";
                        eof = "\n";
                }
                fputs(eof, stdout);
                return 0;
        }

        if (read_cache() < 0)
                die("index file corrupt");

        if (dir.ignored_nr) {
                fprintf(stderr, ignore_warning);
                for (i = 0; i < dir.ignored_nr; i++) {
                        fprintf(stderr, "%s\n", dir.ignored[i]->name);
                }
                fprintf(stderr, "Use -f if you really want to add them.\n");
                exit(1);
        }

        for (i = 0; i < dir.nr; i++)
                add_file_to_cache(dir.entries[i]->name, verbose);

 finish:
        if (active_cache_changed) {
                if (write_cache(newfd, active_cache, active_nr) ||
                    close(newfd) || commit_locked_index(&lock_file))
                        die("Unable to write new index file");
        }

        return 0;
}