/*
 * "git add" builtin command
 *
 * Copyright (C) 2006 Linus Torvalds
 */
#include "cache.h"
#include "builtin.h"
#include "dir.h"
#include "pathspec.h"
#include "exec_cmd.h"
#include "cache-tree.h"
#include "run-command.h"
#include "parse-options.h"
#include "diff.h"
#include "diffcore.h"
#include "revision.h"
#include "bulk-checkin.h"

static const char * const builtin_add_usage[] = {
        N_("git add [options] [--] <pathspec>..."),
        NULL
};
static int patch_interactive, add_interactive, edit_interactive;
static int take_worktree_changes;

struct update_callback_data {
        int flags;
        int add_errors;
        const char *implicit_dot;
        size_t implicit_dot_len;

        /* only needed for 2.0 transition preparation */
        int warn_add_would_remove;
};

static const char *option_with_implicit_dot;
static const char *short_option_with_implicit_dot;

static void warn_pathless_add(void)
{
        static int shown;
        assert(option_with_implicit_dot && short_option_with_implicit_dot);

        if (shown)
                return;
        shown = 1;

        /*
         * To be consistent with "git add -p" and most Git
         * commands, we should default to being tree-wide, but
         * this is not the original behavior and can't be
         * changed until users trained themselves not to type
         * "git add -u" or "git add -A". For now, we warn and
         * keep the old behavior. Later, the behavior can be changed
         * to tree-wide, keeping the warning for a while, and
         * eventually we can drop the warning.
         */
        warning(_("The behavior of 'git add %s (or %s)' with no path argument from a\n"
                  "subdirectory of the tree will change in Git 2.0 and should not be used anymore.\n"
                  "To add content for the whole tree, run:\n"
                  "\n"
                  "  git add %s :/\n"
                  "  (or git add %s :/)\n"
                  "\n"
                  "To restrict the command to the current directory, run:\n"
                  "\n"
                  "  git add %s .\n"
                  "  (or git add %s .)\n"
                  "\n"
                  "With the current Git version, the command is restricted to "
                  "the current directory.\n"
                  ""),
                option_with_implicit_dot, short_option_with_implicit_dot,
                option_with_implicit_dot, short_option_with_implicit_dot,
                option_with_implicit_dot, short_option_with_implicit_dot);
}

static int fix_unmerged_status(struct diff_filepair *p,
                               struct update_callback_data *data)
{
        if (p->status != DIFF_STATUS_UNMERGED)
                return p->status;
        if (!(data->flags & ADD_CACHE_IGNORE_REMOVAL) && !p->two->mode)
                /*
                 * This is not an explicit add request, and the
                 * path is missing from the working tree (deleted)
                 */
                return DIFF_STATUS_DELETED;
        else
                /*
                 * Either an explicit add request, or path exists
                 * in the working tree.  An attempt to explicitly
                 * add a path that does not exist in the working tree
                 * will be caught as an error by the caller immediately.
                 */
                return DIFF_STATUS_MODIFIED;
}

static const char *add_would_remove_warning = N_(
        "You ran 'git add' with neither '-A (--all)' or '--ignore-removal',\n"
"whose behaviour will change in Git 2.0 with respect to paths you removed.\n"
"Paths like '%s' that are\n"
"removed from your working tree are ignored with this version of Git.\n"
"\n"
"* 'git add --ignore-removal <pathspec>', which is the current default,\n"
"  ignores paths you removed from your working tree.\n"
"\n"
"* 'git add --all <pathspec>' will let you also record the removals.\n"
"\n"
"Run 'git status' to check the paths you removed from your working tree.\n");

static void warn_add_would_remove(const char *path)
{
        warning(_(add_would_remove_warning), path);
}

static void update_callback(struct diff_queue_struct *q,
                            struct diff_options *opt, void *cbdata)
{
        int i;
        struct update_callback_data *data = cbdata;
        const char *implicit_dot = data->implicit_dot;
        size_t implicit_dot_len = data->implicit_dot_len;

        for (i = 0; i < q->nr; i++) {
                struct diff_filepair *p = q->queue[i];
                const char *path = p->one->path;
                /*
                 * Check if "git add -A" or "git add -u" was run from a
                 * subdirectory with a modified file outside that directory,
                 * and warn if so.
                 *
                 * "git add -u" will behave like "git add -u :/" instead of
                 * "git add -u ." in the future.  This warning prepares for
                 * that change.
                 */
                if (implicit_dot &&
                    strncmp_icase(path, implicit_dot, implicit_dot_len)) {
                        warn_pathless_add();
                        continue;
                }
                switch (fix_unmerged_status(p, data)) {
                default:
                        die(_("unexpected diff status %c"), p->status);
                case DIFF_STATUS_MODIFIED:
                case DIFF_STATUS_TYPE_CHANGED:
                        if (add_file_to_index(&the_index, path, data->flags)) {
                                if (!(data->flags & ADD_CACHE_IGNORE_ERRORS))
                                        die(_("updating files failed"));
                                data->add_errors++;
                        }
                        break;
                case DIFF_STATUS_DELETED:
                        if (data->warn_add_would_remove) {
                                warn_add_would_remove(path);
                                data->warn_add_would_remove = 0;
                        }
                        if (data->flags & ADD_CACHE_IGNORE_REMOVAL)
                                break;
                        if (!(data->flags & ADD_CACHE_PRETEND))
                                remove_file_from_index(&the_index, path);
                        if (data->flags & (ADD_CACHE_PRETEND|ADD_CACHE_VERBOSE))
                                printf(_("remove '%s'\n"), path);
                        break;
                }
        }
}

static void update_files_in_cache(const char *prefix,
                                  const struct pathspec *pathspec,
                                  struct update_callback_data *data)
{
        struct rev_info rev;

        init_revisions(&rev, prefix);
        setup_revisions(0, NULL, &rev, NULL);
        if (pathspec)
                copy_pathspec(&rev.prune_data, pathspec);
        rev.diffopt.output_format = DIFF_FORMAT_CALLBACK;
        rev.diffopt.format_callback = update_callback;
        rev.diffopt.format_callback_data = data;
        rev.max_count = 0; /* do not compare unmerged paths with stage #2 */
        run_diff_files(&rev, DIFF_RACY_IS_MODIFIED);
}

int add_files_to_cache(const char *prefix,
                       const struct pathspec *pathspec, int flags)
{
        struct update_callback_data data;

        memset(&data, 0, sizeof(data));
        data.flags = flags;
        update_files_in_cache(prefix, pathspec, &data);
        return !!data.add_errors;
}

#define WARN_IMPLICIT_DOT (1u << 0)
static char *prune_directory(struct dir_struct *dir, struct pathspec *pathspec,
                             int prefix, unsigned flag)
{
        char *seen;
        int i;
        struct dir_entry **src, **dst;

        seen = xcalloc(pathspec->nr, 1);

        src = dst = dir->entries;
        i = dir->nr;
        while (--i >= 0) {
                struct dir_entry *entry = *src++;
                if (match_pathspec_depth(pathspec, entry->name, entry->len,
                                         prefix, seen))
                        *dst++ = entry;
                else if (flag & WARN_IMPLICIT_DOT)
                        /*
                         * "git add -A" was run from a subdirectory with a
                         * new file outside that directory.
                         *
                         * "git add -A" will behave like "git add -A :/"
                         * instead of "git add -A ." in the future.
                         * Warn about the coming behavior change.
                         */
                        warn_pathless_add();
        }
        dir->nr = dst - dir->entries;
        add_pathspec_matches_against_index(pathspec, seen);
        return seen;
}

static void refresh(int verbose, const struct pathspec *pathspec)
{
        char *seen;
        int i;

        seen = xcalloc(pathspec->nr, 1);
        refresh_index(&the_index, verbose ? REFRESH_IN_PORCELAIN : REFRESH_QUIET,
                      pathspec, seen, _("Unstaged changes after refreshing the index:"));
        for (i = 0; i < pathspec->nr; i++) {
                if (!seen[i])
                        die(_("pathspec '%s' did not match any files"),
                            pathspec->items[i].match);
        }
        free(seen);
}

int run_add_interactive(const char *revision, const char *patch_mode,
                        const struct pathspec *pathspec)
{
        int status, ac, i;
        const char **args;

        args = xcalloc(sizeof(const char *), (pathspec->nr + 6));
        ac = 0;
        args[ac++] = "add--interactive";
        if (patch_mode)
                args[ac++] = patch_mode;
        if (revision)
                args[ac++] = revision;
        args[ac++] = "--";
        for (i = 0; i < pathspec->nr; i++)
                /* pass original pathspec, to be re-parsed */
                args[ac++] = pathspec->items[i].original;

        status = run_command_v_opt(args, RUN_GIT_CMD);
        free(args);
        return status;
}

int interactive_add(int argc, const char **argv, const char *prefix, int patch)
{
        struct pathspec pathspec;

        /*
         * git-add--interactive itself does not parse pathspec. It
         * simply passes the pathspec to other builtin commands. Let's
         * hope all of them support all magic, or we'll need to limit
         * the magic here.
         */
        parse_pathspec(&pathspec, PATHSPEC_ALL_MAGIC & ~PATHSPEC_FROMTOP,
                       PATHSPEC_PREFER_FULL |
                       PATHSPEC_SYMLINK_LEADING_PATH |
                       PATHSPEC_PREFIX_ORIGIN,
                       prefix, argv);

        return run_add_interactive(NULL,
                                   patch ? "--patch" : NULL,
                                   &pathspec);
}

static int edit_patch(int argc, const char **argv, const char *prefix)
{
        char *file = git_pathdup("ADD_EDIT.patch");
        const char *apply_argv[] = { "apply", "--recount", "--cached",
                NULL, NULL };
        struct child_process child;
        struct rev_info rev;
        int out;
        struct stat st;

        apply_argv[3] = file;

        git_config(git_diff_basic_config, NULL); /* no "diff" UI options */

        if (read_cache() < 0)
                die (_("Could not read the index"));

        init_revisions(&rev, prefix);
        rev.diffopt.context = 7;

        argc = setup_revisions(argc, argv, &rev, NULL);
        rev.diffopt.output_format = DIFF_FORMAT_PATCH;
        DIFF_OPT_SET(&rev.diffopt, IGNORE_DIRTY_SUBMODULES);
        out = open(file, O_CREAT | O_WRONLY, 0666);
        if (out < 0)
                die (_("Could not open '%s' for writing."), file);
        rev.diffopt.file = xfdopen(out, "w");
        rev.diffopt.close_file = 1;
        if (run_diff_files(&rev, 0))
                die (_("Could not write patch"));

        launch_editor(file, NULL, NULL);

        if (stat(file, &st))
                die_errno(_("Could not stat '%s'"), file);
        if (!st.st_size)
                die(_("Empty patch. Aborted."));

        memset(&child, 0, sizeof(child));
        child.git_cmd = 1;
        child.argv = apply_argv;
        if (run_command(&child))
                die (_("Could not apply '%s'"), file);

        unlink(file);
        free(file);
        return 0;
}

static struct lock_file lock_file;

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

static int verbose, show_only, ignored_too, refresh_only;
static int ignore_add_errors, intent_to_add, ignore_missing;

#define ADDREMOVE_DEFAULT 0 /* Change to 1 in Git 2.0 */
static int addremove = ADDREMOVE_DEFAULT;
static int addremove_explicit = -1; /* unspecified */

static int ignore_removal_cb(const struct option *opt, const char *arg, int unset)
{
        /* if we are told to ignore, we are not adding removals */
        *(int *)opt->value = !unset ? 0 : 1;
        return 0;
}

static struct option builtin_add_options[] = {
        OPT__DRY_RUN(&show_only, N_("dry run")),
        OPT__VERBOSE(&verbose, N_("be verbose")),
        OPT_GROUP(""),
        OPT_BOOL('i', "interactive", &add_interactive, N_("interactive picking")),
        OPT_BOOL('p', "patch", &patch_interactive, N_("select hunks interactively")),
        OPT_BOOL('e', "edit", &edit_interactive, N_("edit current diff and apply")),
        OPT__FORCE(&ignored_too, N_("allow adding otherwise ignored files")),
        OPT_BOOL('u', "update", &take_worktree_changes, N_("update tracked files")),
        OPT_BOOL('N', "intent-to-add", &intent_to_add, N_("record only the fact that the path will be added later")),
        OPT_BOOL('A', "all", &addremove_explicit, N_("add changes from all tracked and untracked files")),
        { OPTION_CALLBACK, 0, "ignore-removal", &addremove_explicit,
          NULL /* takes no arguments */,
          N_("ignore paths removed in the working tree (same as --no-all)"),
          PARSE_OPT_NOARG, ignore_removal_cb },
        OPT_BOOL( 0 , "refresh", &refresh_only, N_("don't add, only refresh the index")),
        OPT_BOOL( 0 , "ignore-errors", &ignore_add_errors, N_("just skip files which cannot be added because of errors")),
        OPT_BOOL( 0 , "ignore-missing", &ignore_missing, N_("check if - even missing - files are ignored in dry run")),
        OPT_END(),
};

static int add_config(const char *var, const char *value, void *cb)
{
        if (!strcmp(var, "add.ignoreerrors") ||
            !strcmp(var, "add.ignore-errors")) {
                ignore_add_errors = git_config_bool(var, value);
                return 0;
        }
        return git_default_config(var, value, cb);
}

static int add_files(struct dir_struct *dir, int flags)
{
        int i, exit_status = 0;

        if (dir->ignored_nr) {
                fprintf(stderr, _(ignore_error));
                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"));
                die(_("no files added"));
        }

        for (i = 0; i < dir->nr; i++)
                if (add_file_to_cache(dir->entries[i]->name, flags)) {
                        if (!ignore_add_errors)
                                die(_("adding files failed"));
                        exit_status = 1;
                }
        return exit_status;
}

int cmd_add(int argc, const char **argv, const char *prefix)
{
        int exit_status = 0;
        int newfd;
        struct pathspec pathspec;
        struct dir_struct dir;
        int flags;
        int add_new_files;
        int require_pathspec;
        char *seen = NULL;
        int implicit_dot = 0;
        struct update_callback_data update_data;

        git_config(add_config, NULL);

        argc = parse_options(argc, argv, prefix, builtin_add_options,
                          builtin_add_usage, PARSE_OPT_KEEP_ARGV0);
        if (patch_interactive)
                add_interactive = 1;
        if (add_interactive)
                exit(interactive_add(argc - 1, argv + 1, prefix, patch_interactive));

        if (edit_interactive)
                return(edit_patch(argc, argv, prefix));
        argc--;
        argv++;

        if (0 <= addremove_explicit)
                addremove = addremove_explicit;
        else if (take_worktree_changes && ADDREMOVE_DEFAULT)
                addremove = 0; /* "-u" was given but not "-A" */

        if (addremove && take_worktree_changes)
                die(_("-A and -u are mutually incompatible"));

        /*
         * Warn when "git add pathspec..." was given without "-u" or "-A"
         * and pathspec... covers a removed path.
         */
        memset(&update_data, 0, sizeof(update_data));
        if (!take_worktree_changes && addremove_explicit < 0)
                update_data.warn_add_would_remove = 1;

        if (!take_worktree_changes && addremove_explicit < 0 && argc)
                /*
                 * Turn "git add pathspec..." to "git add -A pathspec..."
                 * in Git 2.0 but not yet
                 */
                ; /* addremove = 1; */

        if (!show_only && ignore_missing)
                die(_("Option --ignore-missing can only be used together with --dry-run"));
        if (addremove) {
                option_with_implicit_dot = "--all";
                short_option_with_implicit_dot = "-A";
        }
        if (take_worktree_changes) {
                option_with_implicit_dot = "--update";
                short_option_with_implicit_dot = "-u";
        }
        if (option_with_implicit_dot && !argc) {
                static const char *here[2] = { ".", NULL };
                argc = 1;
                argv = here;
                implicit_dot = 1;
        }

        add_new_files = !take_worktree_changes && !refresh_only;
        require_pathspec = !take_worktree_changes;

        newfd = hold_locked_index(&lock_file, 1);

        flags = ((verbose ? ADD_CACHE_VERBOSE : 0) |
                 (show_only ? ADD_CACHE_PRETEND : 0) |
                 (intent_to_add ? ADD_CACHE_INTENT : 0) |
                 (ignore_add_errors ? ADD_CACHE_IGNORE_ERRORS : 0) |
                 (!(addremove || take_worktree_changes)
                  ? ADD_CACHE_IGNORE_REMOVAL : 0)) |
                 (implicit_dot ? ADD_CACHE_IMPLICIT_DOT : 0);

        if (require_pathspec && argc == 0) {
                fprintf(stderr, _("Nothing specified, nothing added.\n"));
                fprintf(stderr, _("Maybe you wanted to say 'git add .'?\n"));
                return 0;
        }

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

        /*
         * Check the "pathspec '%s' did not match any files" block
         * below before enabling new magic.
         */
        parse_pathspec(&pathspec, 0,
                       PATHSPEC_PREFER_FULL |
                       PATHSPEC_SYMLINK_LEADING_PATH |
                       PATHSPEC_STRIP_SUBMODULE_SLASH_EXPENSIVE,
                       prefix, argv);

        if (add_new_files) {
                int baselen;
                struct pathspec empty_pathspec;

                /* Set up the default git porcelain excludes */
                memset(&dir, 0, sizeof(dir));
                if (!ignored_too) {
                        dir.flags |= DIR_COLLECT_IGNORED;
                        setup_standard_excludes(&dir);
                }

                memset(&empty_pathspec, 0, sizeof(empty_pathspec));
                /* This picks up the paths that are not tracked */
                baselen = fill_directory(&dir, implicit_dot ? &empty_pathspec : &pathspec);
                if (pathspec.nr)
                        seen = prune_directory(&dir, &pathspec, baselen,
                                        implicit_dot ? WARN_IMPLICIT_DOT : 0);
        }

        if (refresh_only) {
                refresh(verbose, &pathspec);
                goto finish;
        }
        if (implicit_dot && prefix)
                refresh_cache(REFRESH_QUIET);

        if (pathspec.nr) {
                int i;

                if (!seen)
                        seen = find_pathspecs_matching_against_index(&pathspec);

                /*
                 * file_exists() assumes exact match
                 */
                GUARD_PATHSPEC(&pathspec, PATHSPEC_FROMTOP);

                for (i = 0; i < pathspec.nr; i++) {
                        const char *path = pathspec.items[i].match;
                        if (!seen[i] && !file_exists(path)) {
                                if (ignore_missing) {
                                        int dtype = DT_UNKNOWN;
                                        if (is_excluded(&dir, path, &dtype))
                                                dir_add_ignored(&dir, path, pathspec.items[i].len);
                                } else
                                        die(_("pathspec '%s' did not match any files"),
                                            pathspec.items[i].original);
                        }
                }
                free(seen);
        }

        plug_bulk_checkin();

        if ((flags & ADD_CACHE_IMPLICIT_DOT) && prefix) {
                /*
                 * Check for modified files throughout the worktree so
                 * update_callback has a chance to warn about changes
                 * outside the cwd.
                 */
                update_data.implicit_dot = prefix;
                update_data.implicit_dot_len = strlen(prefix);
                free_pathspec(&pathspec);
                memset(&pathspec, 0, sizeof(pathspec));
        }
        update_data.flags = flags & ~ADD_CACHE_IMPLICIT_DOT;
        update_files_in_cache(prefix, &pathspec, &update_data);

        exit_status |= !!update_data.add_errors;
        if (add_new_files)
                exit_status |= add_files(&dir, flags);

        unplug_bulk_checkin();

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

        return exit_status;
}