/*
 * "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 "run-command.h"
#include "parse-options.h"
#include "diff.h"
#include "diffcore.h"
#include "revision.h"

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

struct update_callback_data
{
        int flags;
        int add_errors;
};

static void update_callback(struct diff_queue_struct *q,
                            struct diff_options *opt, void *cbdata)
{
        int i;
        struct update_callback_data *data = 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("unexpected diff status %c", p->status);
                case DIFF_STATUS_UNMERGED:
                        /*
                         * ADD_CACHE_IGNORE_REMOVAL is unset if "git
                         * add -u" is calling us, In such a case, a
                         * missing work tree file needs to be removed
                         * if there is an unmerged entry at stage #2,
                         * but such a diff record is followed by
                         * another with DIFF_STATUS_DELETED (and if
                         * there is no stage #2, we won't see DELETED
                         * nor MODIFIED).  We can simply continue
                         * either way.
                         */
                        if (!(data->flags & ADD_CACHE_IGNORE_REMOVAL))
                                continue;
                        /*
                         * Otherwise, it is "git add path" is asking
                         * to explicitly add it; we fall through.  A
                         * missing work tree file is an error and is
                         * caught by add_file_to_index() in such a
                         * case.
                         */
                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->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;
                }
        }
}

int add_files_to_cache(const char *prefix, const char **pathspec, int flags)
{
        struct update_callback_data data;
        struct rev_info rev;
        init_revisions(&rev, prefix);
        setup_revisions(0, NULL, &rev, NULL);
        rev.prune_data = pathspec;
        rev.diffopt.output_format = DIFF_FORMAT_CALLBACK;
        rev.diffopt.format_callback = update_callback;
        data.flags = flags;
        data.add_errors = 0;
        rev.diffopt.format_callback_data = &data;
        run_diff_files(&rev, DIFF_RACY_IS_MODIFIED);
        return !!data.add_errors;
}

static void fill_pathspec_matches(const char **pathspec, char *seen, int specs)
{
        int num_unmatched = 0, i;

        /*
         * Since we are walking the index as if we were walking the directory,
         * we have to mark the matched pathspec as seen; otherwise we will
         * mistakenly think that the user gave a pathspec that did not match
         * anything.
         */
        for (i = 0; i < specs; i++)
                if (!seen[i])
                        num_unmatched++;
        if (!num_unmatched)
                return;
        for (i = 0; i < active_nr; i++) {
                struct cache_entry *ce = active_cache[i];
                match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, seen);
        }
}

static char *find_used_pathspec(const char **pathspec)
{
        char *seen;
        int i;

        for (i = 0; pathspec[i];  i++)
                ; /* just counting */
        seen = xcalloc(i, 1);
        fill_pathspec_matches(pathspec, seen, i);
        return seen;
}

static char *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;
        fill_pathspec_matches(pathspec, seen, specs);
        return seen;
}

static void treat_gitlinks(const char **pathspec)
{
        int i;

        if (!pathspec || !*pathspec)
                return;

        for (i = 0; i < active_nr; i++) {
                struct cache_entry *ce = active_cache[i];
                if (S_ISGITLINK(ce->ce_mode)) {
                        int len = ce_namelen(ce), j;
                        for (j = 0; pathspec[j]; j++) {
                                int len2 = strlen(pathspec[j]);
                                if (len2 <= len || pathspec[j][len] != '/' ||
                                    memcmp(ce->name, pathspec[j], len))
                                        continue;
                                if (len2 == len + 1)
                                        /* strip trailing slash */
                                        pathspec[j] = xstrndup(ce->name, len);
                                else
                                        die ("Path '%s' is in submodule '%.*s'",
                                                pathspec[j], len, ce->name);
                        }
                }
        }
}

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

        for (specs = 0; pathspec[specs];  specs++)
                /* nothing */;
        seen = xcalloc(specs, 1);
        refresh_index(&the_index, verbose ? REFRESH_IN_PORCELAIN : REFRESH_QUIET,
                      pathspec, seen, "Unstaged changes after refreshing the index:");
        for (i = 0; i < specs; i++) {
                if (!seen[i])
                        die("pathspec '%s' did not match any files", pathspec[i]);
        }
        free(seen);
}

static const char **validate_pathspec(int argc, const char **argv, const char *prefix)
{
        const char **pathspec = get_pathspec(prefix, argv);

        if (pathspec) {
                const char **p;
                for (p = pathspec; *p; p++) {
                        if (has_symlink_leading_path(*p, strlen(*p))) {
                                int len = prefix ? strlen(prefix) : 0;
                                die("'%s' is beyond a symbolic link", *p + len);
                        }
                }
        }

        return pathspec;
}

int run_add_interactive(const char *revision, const char *patch_mode,
                        const char **pathspec)
{
        int status, ac, pc = 0;
        const char **args;

        if (pathspec)
                while (pathspec[pc])
                        pc++;

        args = xcalloc(sizeof(const char *), (pc + 5));
        ac = 0;
        args[ac++] = "add--interactive";
        if (patch_mode)
                args[ac++] = patch_mode;
        if (revision)
                args[ac++] = revision;
        args[ac++] = "--";
        if (pc) {
                memcpy(&(args[ac]), pathspec, sizeof(const char *) * pc);
                ac += pc;
        }
        args[ac] = NULL;

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

int interactive_add(int argc, const char **argv, const char *prefix)
{
        const char **pathspec = NULL;

        if (argc) {
                pathspec = validate_pathspec(argc, argv, prefix);
                if (!pathspec)
                        return -1;
        }

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

static int edit_patch(int argc, const char **argv, const char *prefix)
{
        char *file = xstrdup(git_path("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;
        out = open(file, O_CREAT | O_WRONLY, 0644);
        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);
        return 0;
}

static struct lock_file lock_file;

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

static int verbose = 0, show_only = 0, ignored_too = 0, refresh_only = 0;
static int ignore_add_errors, addremove, intent_to_add, ignore_missing = 0;

static struct option builtin_add_options[] = {
        OPT__DRY_RUN(&show_only),
        OPT__VERBOSE(&verbose),
        OPT_GROUP(""),
        OPT_BOOLEAN('i', "interactive", &add_interactive, "interactive picking"),
        OPT_BOOLEAN('p', "patch", &patch_interactive, "interactive patching"),
        OPT_BOOLEAN('e', "edit", &edit_interactive, "edit current diff and apply"),
        OPT_BOOLEAN('f', "force", &ignored_too, "allow adding otherwise ignored files"),
        OPT_BOOLEAN('u', "update", &take_worktree_changes, "update tracked files"),
        OPT_BOOLEAN('N', "intent-to-add", &intent_to_add, "record only the fact that the path will be added later"),
        OPT_BOOLEAN('A', "all", &addremove, "add all, noticing removal of tracked files"),
        OPT_BOOLEAN( 0 , "refresh", &refresh_only, "don't add, only refresh the index"),
        OPT_BOOLEAN( 0 , "ignore-errors", &ignore_add_errors, "just skip files which cannot be added because of errors"),
        OPT_BOOLEAN( 0 , "ignore-missing", &ignore_missing, "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 (!strcasecmp(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;
        const char **pathspec;
        struct dir_struct dir;
        int flags;
        int add_new_files;
        int require_pathspec;
        char *seen = NULL;

        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));

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

        if (addremove && take_worktree_changes)
                die("-A and -u are mutually incompatible");
        if (!show_only && ignore_missing)
                die("Option --ignore-missing can only be used together with --dry-run");
        if ((addremove || take_worktree_changes) && !argc) {
                static const char *here[2] = { ".", NULL };
                argc = 1;
                argv = here;
        }

        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));

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

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

        if (add_new_files) {
                int baselen;

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

                /* This picks up the paths that are not tracked */
                baselen = fill_directory(&dir, pathspec);
                if (pathspec)
                        seen = prune_directory(&dir, pathspec, baselen);
        }

        if (refresh_only) {
                refresh(verbose, pathspec);
                goto finish;
        }

        if (pathspec) {
                int i;
                if (!seen)
                        seen = find_used_pathspec(pathspec);
                for (i = 0; pathspec[i]; i++) {
                        if (!seen[i] && pathspec[i][0]
                            && !file_exists(pathspec[i])) {
                                if (ignore_missing) {
                                        if (excluded(&dir, pathspec[i], DT_UNKNOWN))
                                                dir_add_ignored(&dir, pathspec[i], strlen(pathspec[i]));
                                } else
                                        die("pathspec '%s' did not match any files",
                                            pathspec[i]);
                        }
                }
                free(seen);
        }

        exit_status |= add_files_to_cache(prefix, pathspec, flags);

        if (add_new_files)
                exit_status |= add_files(&dir, flags);

 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;
}