#include "cache.h"
#include "parse-options.h"
#include "transport.h"
#include "remote.h"
#include "string-list.h"
#include "strbuf.h"
#include "run-command.h"
#include "refs.h"

static const char * const builtin_remote_usage[] = {
        "git remote [-v | --verbose]",
        "git remote add [-t <branch>] [-m <master>] [-f] [--mirror] <name> <url>",
        "git remote rename <old> <new>",
        "git remote rm <name>",
        "git remote set-head <name> [-a | -d | <branch>]",
        "git remote show [-n] <name>",
        "git remote prune [-n | --dry-run] <name>",
        "git remote [-v | --verbose] update [group]",
        NULL
};

#define GET_REF_STATES (1<<0)
#define GET_HEAD_NAMES (1<<1)
#define GET_PUSH_REF_STATES (1<<2)

static int verbose;

static int show_all(void);

static inline int postfixcmp(const char *string, const char *postfix)
{
        int len1 = strlen(string), len2 = strlen(postfix);
        if (len1 < len2)
                return 1;
        return strcmp(string + len1 - len2, postfix);
}

static int opt_parse_track(const struct option *opt, const char *arg, int not)
{
        struct string_list *list = opt->value;
        if (not)
                string_list_clear(list, 0);
        else
                string_list_append(arg, list);
        return 0;
}

static int fetch_remote(const char *name)
{
        const char *argv[] = { "fetch", name, NULL, NULL };
        if (verbose) {
                argv[1] = "-v";
                argv[2] = name;
        }
        printf("Updating %s\n", name);
        if (run_command_v_opt(argv, RUN_GIT_CMD))
                return error("Could not fetch %s", name);
        return 0;
}

static int add(int argc, const char **argv)
{
        int fetch = 0, mirror = 0;
        struct string_list track = { NULL, 0, 0 };
        const char *master = NULL;
        struct remote *remote;
        struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT;
        const char *name, *url;
        int i;

        struct option options[] = {
                OPT_GROUP("add specific options"),
                OPT_BOOLEAN('f', "fetch", &fetch, "fetch the remote branches"),
                OPT_CALLBACK('t', "track", &track, "branch",
                        "branch(es) to track", opt_parse_track),
                OPT_STRING('m', "master", &master, "branch", "master branch"),
                OPT_BOOLEAN(0, "mirror", &mirror, "no separate remotes"),
                OPT_END()
        };

        argc = parse_options(argc, argv, options, builtin_remote_usage, 0);

        if (argc < 2)
                usage_with_options(builtin_remote_usage, options);

        name = argv[0];
        url = argv[1];

        remote = remote_get(name);
        if (remote && (remote->url_nr > 1 || strcmp(name, remote->url[0]) ||
                        remote->fetch_refspec_nr))
                die("remote %s already exists.", name);

        strbuf_addf(&buf2, "refs/heads/test:refs/remotes/%s/test", name);
        if (!valid_fetch_refspec(buf2.buf))
                die("'%s' is not a valid remote name", name);

        strbuf_addf(&buf, "remote.%s.url", name);
        if (git_config_set(buf.buf, url))
                return 1;

        strbuf_reset(&buf);
        strbuf_addf(&buf, "remote.%s.fetch", name);

        if (track.nr == 0)
                string_list_append("*", &track);
        for (i = 0; i < track.nr; i++) {
                struct string_list_item *item = track.items + i;

                strbuf_reset(&buf2);
                strbuf_addch(&buf2, '+');
                if (mirror)
                        strbuf_addf(&buf2, "refs/%s:refs/%s",
                                        item->string, item->string);
                else
                        strbuf_addf(&buf2, "refs/heads/%s:refs/remotes/%s/%s",
                                        item->string, name, item->string);
                if (git_config_set_multivar(buf.buf, buf2.buf, "^$", 0))
                        return 1;
        }

        if (mirror) {
                strbuf_reset(&buf);
                strbuf_addf(&buf, "remote.%s.mirror", name);
                if (git_config_set(buf.buf, "true"))
                        return 1;
        }

        if (fetch && fetch_remote(name))
                return 1;

        if (master) {
                strbuf_reset(&buf);
                strbuf_addf(&buf, "refs/remotes/%s/HEAD", name);

                strbuf_reset(&buf2);
                strbuf_addf(&buf2, "refs/remotes/%s/%s", name, master);

                if (create_symref(buf.buf, buf2.buf, "remote add"))
                        return error("Could not setup master '%s'", master);
        }

        strbuf_release(&buf);
        strbuf_release(&buf2);
        string_list_clear(&track, 0);

        return 0;
}

struct branch_info {
        char *remote_name;
        struct string_list merge;
        int rebase;
};

static struct string_list branch_list;

static const char *abbrev_ref(const char *name, const char *prefix)
{
        const char *abbrev = skip_prefix(name, prefix);
        if (abbrev)
                return abbrev;
        return name;
}
#define abbrev_branch(name) abbrev_ref((name), "refs/heads/")

static int config_read_branches(const char *key, const char *value, void *cb)
{
        if (!prefixcmp(key, "branch.")) {
                const char *orig_key = key;
                char *name;
                struct string_list_item *item;
                struct branch_info *info;
                enum { REMOTE, MERGE, REBASE } type;

                key += 7;
                if (!postfixcmp(key, ".remote")) {
                        name = xstrndup(key, strlen(key) - 7);
                        type = REMOTE;
                } else if (!postfixcmp(key, ".merge")) {
                        name = xstrndup(key, strlen(key) - 6);
                        type = MERGE;
                } else if (!postfixcmp(key, ".rebase")) {
                        name = xstrndup(key, strlen(key) - 7);
                        type = REBASE;
                } else
                        return 0;

                item = string_list_insert(name, &branch_list);

                if (!item->util)
                        item->util = xcalloc(sizeof(struct branch_info), 1);
                info = item->util;
                if (type == REMOTE) {
                        if (info->remote_name)
                                warning("more than one %s", orig_key);
                        info->remote_name = xstrdup(value);
                } else if (type == MERGE) {
                        char *space = strchr(value, ' ');
                        value = abbrev_branch(value);
                        while (space) {
                                char *merge;
                                merge = xstrndup(value, space - value);
                                string_list_append(merge, &info->merge);
                                value = abbrev_branch(space + 1);
                                space = strchr(value, ' ');
                        }
                        string_list_append(xstrdup(value), &info->merge);
                } else
                        info->rebase = git_config_bool(orig_key, value);
        }
        return 0;
}

static void read_branches(void)
{
        if (branch_list.nr)
                return;
        git_config(config_read_branches, NULL);
}

struct ref_states {
        struct remote *remote;
        struct string_list new, stale, tracked, heads, push;
        int queried;
};

static int handle_one_branch(const char *refname,
        const unsigned char *sha1, int flags, void *cb_data)
{
        struct ref_states *states = cb_data;
        struct refspec refspec;

        memset(&refspec, 0, sizeof(refspec));
        refspec.dst = (char *)refname;
        if (!remote_find_tracking(states->remote, &refspec)) {
                struct string_list_item *item;
                const char *name = abbrev_branch(refspec.src);
                /* symbolic refs pointing nowhere were handled already */
                if ((flags & REF_ISSYMREF) ||
                    string_list_has_string(&states->tracked, name) ||
                    string_list_has_string(&states->new, name))
                        return 0;
                item = string_list_append(name, &states->stale);
                item->util = xstrdup(refname);
        }
        return 0;
}

static int get_ref_states(const struct ref *remote_refs, struct ref_states *states)
{
        struct ref *fetch_map = NULL, **tail = &fetch_map;
        struct ref *ref;
        int i;

        for (i = 0; i < states->remote->fetch_refspec_nr; i++)
                if (get_fetch_map(remote_refs, states->remote->fetch + i, &tail, 1))
                        die("Could not get fetch map for refspec %s",
                                states->remote->fetch_refspec[i]);

        states->new.strdup_strings = states->tracked.strdup_strings = 1;
        for (ref = fetch_map; ref; ref = ref->next) {
                unsigned char sha1[20];
                if (!ref->peer_ref || read_ref(ref->peer_ref->name, sha1))
                        string_list_append(abbrev_branch(ref->name), &states->new);
                else
                        string_list_append(abbrev_branch(ref->name), &states->tracked);
        }
        free_refs(fetch_map);

        sort_string_list(&states->new);
        sort_string_list(&states->tracked);
        for_each_ref(handle_one_branch, states);
        sort_string_list(&states->stale);

        return 0;
}

struct push_info {
        char *dest;
        int forced;
        enum {
                PUSH_STATUS_CREATE = 0,
                PUSH_STATUS_DELETE,
                PUSH_STATUS_UPTODATE,
                PUSH_STATUS_FASTFORWARD,
                PUSH_STATUS_OUTOFDATE,
                PUSH_STATUS_NOTQUERIED,
        } status;
};

static int get_push_ref_states(const struct ref *remote_refs,
        struct ref_states *states)
{
        struct remote *remote = states->remote;
        struct ref *ref, *local_refs, *push_map, **push_tail;
        if (remote->mirror)
                return 0;

        local_refs = get_local_heads();
        ref = push_map = copy_ref_list(remote_refs);
        while (ref->next)
                ref = ref->next;
        push_tail = &ref->next;

        match_refs(local_refs, push_map, &push_tail, remote->push_refspec_nr,
                   remote->push_refspec, MATCH_REFS_NONE);

        states->push.strdup_strings = 1;
        for (ref = push_map; ref; ref = ref->next) {
                struct string_list_item *item;
                struct push_info *info;

                if (!ref->peer_ref)
                        continue;
                hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);

                item = string_list_append(abbrev_branch(ref->peer_ref->name),
                                          &states->push);
                item->util = xcalloc(sizeof(struct push_info), 1);
                info = item->util;
                info->forced = ref->force;
                info->dest = xstrdup(abbrev_branch(ref->name));

                if (is_null_sha1(ref->new_sha1)) {
                        info->status = PUSH_STATUS_DELETE;
                } else if (!hashcmp(ref->old_sha1, ref->new_sha1))
                        info->status = PUSH_STATUS_UPTODATE;
                else if (is_null_sha1(ref->old_sha1))
                        info->status = PUSH_STATUS_CREATE;
                else if (has_sha1_file(ref->old_sha1) &&
                         ref_newer(ref->new_sha1, ref->old_sha1))
                        info->status = PUSH_STATUS_FASTFORWARD;
                else
                        info->status = PUSH_STATUS_OUTOFDATE;
        }
        free_refs(local_refs);
        free_refs(push_map);
        return 0;
}

static int get_push_ref_states_noquery(struct ref_states *states)
{
        int i;
        struct remote *remote = states->remote;
        struct string_list_item *item;
        struct push_info *info;

        if (remote->mirror)
                return 0;

        states->push.strdup_strings = 1;
        if (!remote->push_refspec_nr) {
                item = string_list_append("(matching)", &states->push);
                info = item->util = xcalloc(sizeof(struct push_info), 1);
                info->status = PUSH_STATUS_NOTQUERIED;
                info->dest = xstrdup(item->string);
        }
        for (i = 0; i < remote->push_refspec_nr; i++) {
                struct refspec *spec = remote->push + i;
                char buf[PATH_MAX];
                if (spec->matching)
                        item = string_list_append("(matching)", &states->push);
                else if (spec->pattern) {
                        snprintf(buf, (sizeof(buf)), "%s*", spec->src);
                        item = string_list_append(buf, &states->push);
                        snprintf(buf, (sizeof(buf)), "%s*", spec->dst);
                } else if (strlen(spec->src))
                        item = string_list_append(spec->src, &states->push);
                else
                        item = string_list_append("(delete)", &states->push);

                info = item->util = xcalloc(sizeof(struct push_info), 1);
                info->forced = spec->force;
                info->status = PUSH_STATUS_NOTQUERIED;
                if (spec->pattern)
                        info->dest = xstrdup(buf);
                else
                        info->dest = xstrdup(spec->dst ? spec->dst : item->string);
        }
        return 0;
}

static int get_head_names(const struct ref *remote_refs, struct ref_states *states)
{
        struct ref *ref, *matches;
        struct ref *fetch_map = NULL, **fetch_map_tail = &fetch_map;
        struct refspec refspec;

        refspec.force = 0;
        refspec.pattern = 1;
        refspec.src = refspec.dst = "refs/heads/";
        states->heads.strdup_strings = 1;
        get_fetch_map(remote_refs, &refspec, &fetch_map_tail, 0);
        matches = guess_remote_head(find_ref_by_name(remote_refs, "HEAD"),
                                    fetch_map, 1);
        for(ref = matches; ref; ref = ref->next)
                string_list_append(abbrev_branch(ref->name), &states->heads);

        free_refs(fetch_map);
        free_refs(matches);

        return 0;
}

struct known_remote {
        struct known_remote *next;
        struct remote *remote;
};

struct known_remotes {
        struct remote *to_delete;
        struct known_remote *list;
};

static int add_known_remote(struct remote *remote, void *cb_data)
{
        struct known_remotes *all = cb_data;
        struct known_remote *r;

        if (!strcmp(all->to_delete->name, remote->name))
                return 0;

        r = xmalloc(sizeof(*r));
        r->remote = remote;
        r->next = all->list;
        all->list = r;
        return 0;
}

struct branches_for_remote {
        struct remote *remote;
        struct string_list *branches, *skipped;
        struct known_remotes *keep;
};

static int add_branch_for_removal(const char *refname,
        const unsigned char *sha1, int flags, void *cb_data)
{
        struct branches_for_remote *branches = cb_data;
        struct refspec refspec;
        struct string_list_item *item;
        struct known_remote *kr;

        memset(&refspec, 0, sizeof(refspec));
        refspec.dst = (char *)refname;
        if (remote_find_tracking(branches->remote, &refspec))
                return 0;

        /* don't delete a branch if another remote also uses it */
        for (kr = branches->keep->list; kr; kr = kr->next) {
                memset(&refspec, 0, sizeof(refspec));
                refspec.dst = (char *)refname;
                if (!remote_find_tracking(kr->remote, &refspec))
                        return 0;
        }

        /* don't delete non-remote refs */
        if (prefixcmp(refname, "refs/remotes")) {
                /* advise user how to delete local branches */
                if (!prefixcmp(refname, "refs/heads/"))
                        string_list_append(abbrev_branch(refname),
                                           branches->skipped);
                /* silently skip over other non-remote refs */
                return 0;
        }

        /* make sure that symrefs are deleted */
        if (flags & REF_ISSYMREF)
                return unlink(git_path("%s", refname));

        item = string_list_append(refname, branches->branches);
        item->util = xmalloc(20);
        hashcpy(item->util, sha1);

        return 0;
}

struct rename_info {
        const char *old;
        const char *new;
        struct string_list *remote_branches;
};

static int read_remote_branches(const char *refname,
        const unsigned char *sha1, int flags, void *cb_data)
{
        struct rename_info *rename = cb_data;
        struct strbuf buf = STRBUF_INIT;
        struct string_list_item *item;
        int flag;
        unsigned char orig_sha1[20];
        const char *symref;

        strbuf_addf(&buf, "refs/remotes/%s", rename->old);
        if(!prefixcmp(refname, buf.buf)) {
                item = string_list_append(xstrdup(refname), rename->remote_branches);
                symref = resolve_ref(refname, orig_sha1, 1, &flag);
                if (flag & REF_ISSYMREF)
                        item->util = xstrdup(symref);
                else
                        item->util = NULL;
        }

        return 0;
}

static int migrate_file(struct remote *remote)
{
        struct strbuf buf = STRBUF_INIT;
        int i;
        char *path = NULL;

        strbuf_addf(&buf, "remote.%s.url", remote->name);
        for (i = 0; i < remote->url_nr; i++)
                if (git_config_set_multivar(buf.buf, remote->url[i], "^$", 0))
                        return error("Could not append '%s' to '%s'",
                                        remote->url[i], buf.buf);
        strbuf_reset(&buf);
        strbuf_addf(&buf, "remote.%s.push", remote->name);
        for (i = 0; i < remote->push_refspec_nr; i++)
                if (git_config_set_multivar(buf.buf, remote->push_refspec[i], "^$", 0))
                        return error("Could not append '%s' to '%s'",
                                        remote->push_refspec[i], buf.buf);
        strbuf_reset(&buf);
        strbuf_addf(&buf, "remote.%s.fetch", remote->name);
        for (i = 0; i < remote->fetch_refspec_nr; i++)
                if (git_config_set_multivar(buf.buf, remote->fetch_refspec[i], "^$", 0))
                        return error("Could not append '%s' to '%s'",
                                        remote->fetch_refspec[i], buf.buf);
        if (remote->origin == REMOTE_REMOTES)
                path = git_path("remotes/%s", remote->name);
        else if (remote->origin == REMOTE_BRANCHES)
                path = git_path("branches/%s", remote->name);
        if (path && unlink(path))
                warning("failed to remove '%s'", path);
        return 0;
}

static int mv(int argc, const char **argv)
{
        struct option options[] = {
                OPT_END()
        };
        struct remote *oldremote, *newremote;
        struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT, buf3 = STRBUF_INIT;
        struct string_list remote_branches = { NULL, 0, 0, 0 };
        struct rename_info rename;
        int i;

        if (argc != 3)
                usage_with_options(builtin_remote_usage, options);

        rename.old = argv[1];
        rename.new = argv[2];
        rename.remote_branches = &remote_branches;

        oldremote = remote_get(rename.old);
        if (!oldremote)
                die("No such remote: %s", rename.old);

        if (!strcmp(rename.old, rename.new) && oldremote->origin != REMOTE_CONFIG)
                return migrate_file(oldremote);

        newremote = remote_get(rename.new);
        if (newremote && (newremote->url_nr > 1 || newremote->fetch_refspec_nr))
                die("remote %s already exists.", rename.new);

        strbuf_addf(&buf, "refs/heads/test:refs/remotes/%s/test", rename.new);
        if (!valid_fetch_refspec(buf.buf))
                die("'%s' is not a valid remote name", rename.new);

        strbuf_reset(&buf);
        strbuf_addf(&buf, "remote.%s", rename.old);
        strbuf_addf(&buf2, "remote.%s", rename.new);
        if (git_config_rename_section(buf.buf, buf2.buf) < 1)
                return error("Could not rename config section '%s' to '%s'",
                                buf.buf, buf2.buf);

        strbuf_reset(&buf);
        strbuf_addf(&buf, "remote.%s.fetch", rename.new);
        if (git_config_set_multivar(buf.buf, NULL, NULL, 1))
                return error("Could not remove config section '%s'", buf.buf);
        for (i = 0; i < oldremote->fetch_refspec_nr; i++) {
                char *ptr;

                strbuf_reset(&buf2);
                strbuf_addstr(&buf2, oldremote->fetch_refspec[i]);
                ptr = strstr(buf2.buf, rename.old);
                if (ptr)
                        strbuf_splice(&buf2, ptr-buf2.buf, strlen(rename.old),
                                        rename.new, strlen(rename.new));
                if (git_config_set_multivar(buf.buf, buf2.buf, "^$", 0))
                        return error("Could not append '%s'", buf.buf);
        }

        read_branches();
        for (i = 0; i < branch_list.nr; i++) {
                struct string_list_item *item = branch_list.items + i;
                struct branch_info *info = item->util;
                if (info->remote_name && !strcmp(info->remote_name, rename.old)) {
                        strbuf_reset(&buf);
                        strbuf_addf(&buf, "branch.%s.remote", item->string);
                        if (git_config_set(buf.buf, rename.new)) {
                                return error("Could not set '%s'", buf.buf);
                        }
                }
        }

        /*
         * First remove symrefs, then rename the rest, finally create
         * the new symrefs.
         */
        for_each_ref(read_remote_branches, &rename);
        for (i = 0; i < remote_branches.nr; i++) {
                struct string_list_item *item = remote_branches.items + i;
                int flag = 0;
                unsigned char sha1[20];

                resolve_ref(item->string, sha1, 1, &flag);
                if (!(flag & REF_ISSYMREF))
                        continue;
                if (delete_ref(item->string, NULL, REF_NODEREF))
                        die("deleting '%s' failed", item->string);
        }
        for (i = 0; i < remote_branches.nr; i++) {
                struct string_list_item *item = remote_branches.items + i;

                if (item->util)
                        continue;
                strbuf_reset(&buf);
                strbuf_addstr(&buf, item->string);
                strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old),
                                rename.new, strlen(rename.new));
                strbuf_reset(&buf2);
                strbuf_addf(&buf2, "remote: renamed %s to %s",
                                item->string, buf.buf);
                if (rename_ref(item->string, buf.buf, buf2.buf))
                        die("renaming '%s' failed", item->string);
        }
        for (i = 0; i < remote_branches.nr; i++) {
                struct string_list_item *item = remote_branches.items + i;

                if (!item->util)
                        continue;
                strbuf_reset(&buf);
                strbuf_addstr(&buf, item->string);
                strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old),
                                rename.new, strlen(rename.new));
                strbuf_reset(&buf2);
                strbuf_addstr(&buf2, item->util);
                strbuf_splice(&buf2, strlen("refs/remotes/"), strlen(rename.old),
                                rename.new, strlen(rename.new));
                strbuf_reset(&buf3);
                strbuf_addf(&buf3, "remote: renamed %s to %s",
                                item->string, buf.buf);
                if (create_symref(buf.buf, buf2.buf, buf3.buf))
                        die("creating '%s' failed", buf.buf);
        }
        return 0;
}

static int remove_branches(struct string_list *branches)
{
        int i, result = 0;
        for (i = 0; i < branches->nr; i++) {
                struct string_list_item *item = branches->items + i;
                const char *refname = item->string;
                unsigned char *sha1 = item->util;

                if (delete_ref(refname, sha1, 0))
                        result |= error("Could not remove branch %s", refname);
        }
        return result;
}

static int rm(int argc, const char **argv)
{
        struct option options[] = {
                OPT_END()
        };
        struct remote *remote;
        struct strbuf buf = STRBUF_INIT;
        struct known_remotes known_remotes = { NULL, NULL };
        struct string_list branches = { NULL, 0, 0, 1 };
        struct string_list skipped = { NULL, 0, 0, 1 };
        struct branches_for_remote cb_data = {
                NULL, &branches, &skipped, &known_remotes
        };
        int i, result;

        if (argc != 2)
                usage_with_options(builtin_remote_usage, options);

        remote = remote_get(argv[1]);
        if (!remote)
                die("No such remote: %s", argv[1]);

        known_remotes.to_delete = remote;
        for_each_remote(add_known_remote, &known_remotes);

        strbuf_addf(&buf, "remote.%s", remote->name);
        if (git_config_rename_section(buf.buf, NULL) < 1)
                return error("Could not remove config section '%s'", buf.buf);

        read_branches();
        for (i = 0; i < branch_list.nr; i++) {
                struct string_list_item *item = branch_list.items + i;
                struct branch_info *info = item->util;
                if (info->remote_name && !strcmp(info->remote_name, remote->name)) {
                        const char *keys[] = { "remote", "merge", NULL }, **k;
                        for (k = keys; *k; k++) {
                                strbuf_reset(&buf);
                                strbuf_addf(&buf, "branch.%s.%s",
                                                item->string, *k);
                                if (git_config_set(buf.buf, NULL)) {
                                        strbuf_release(&buf);
                                        return -1;
                                }
                        }
                }
        }

        /*
         * We cannot just pass a function to for_each_ref() which deletes
         * the branches one by one, since for_each_ref() relies on cached
         * refs, which are invalidated when deleting a branch.
         */
        cb_data.remote = remote;
        result = for_each_ref(add_branch_for_removal, &cb_data);
        strbuf_release(&buf);

        if (!result)
                result = remove_branches(&branches);
        string_list_clear(&branches, 1);

        if (skipped.nr) {
                fprintf(stderr, skipped.nr == 1 ?
                        "Note: A non-remote branch was not removed; "
                        "to delete it, use:\n" :
                        "Note: Non-remote branches were not removed; "
                        "to delete them, use:\n");
                for (i = 0; i < skipped.nr; i++)
                        fprintf(stderr, "  git branch -d %s\n",
                                skipped.items[i].string);
        }
        string_list_clear(&skipped, 0);

        return result;
}

void clear_push_info(void *util, const char *string)
{
        struct push_info *info = util;
        free(info->dest);
        free(info);
}

static void free_remote_ref_states(struct ref_states *states)
{
        string_list_clear(&states->new, 0);
        string_list_clear(&states->stale, 0);
        string_list_clear(&states->tracked, 0);
        string_list_clear(&states->heads, 0);
        string_list_clear_func(&states->push, clear_push_info);
}

static int append_ref_to_tracked_list(const char *refname,
        const unsigned char *sha1, int flags, void *cb_data)
{
        struct ref_states *states = cb_data;
        struct refspec refspec;

        if (flags & REF_ISSYMREF)
                return 0;

        memset(&refspec, 0, sizeof(refspec));
        refspec.dst = (char *)refname;
        if (!remote_find_tracking(states->remote, &refspec))
                string_list_append(abbrev_branch(refspec.src), &states->tracked);

        return 0;
}

static int get_remote_ref_states(const char *name,
                                 struct ref_states *states,
                                 int query)
{
        struct transport *transport;
        const struct ref *remote_refs;

        states->remote = remote_get(name);
        if (!states->remote)
                return error("No such remote: %s", name);

        read_branches();

        if (query) {
                transport = transport_get(NULL, states->remote->url_nr > 0 ?
                        states->remote->url[0] : NULL);
                remote_refs = transport_get_remote_refs(transport);
                transport_disconnect(transport);

                states->queried = 1;
                if (query & GET_REF_STATES)
                        get_ref_states(remote_refs, states);
                if (query & GET_HEAD_NAMES)
                        get_head_names(remote_refs, states);
                if (query & GET_PUSH_REF_STATES)
                        get_push_ref_states(remote_refs, states);
        } else {
                for_each_ref(append_ref_to_tracked_list, states);
                sort_string_list(&states->tracked);
                get_push_ref_states_noquery(states);
        }

        return 0;
}

struct show_info {
        struct string_list *list;
        struct ref_states *states;
        int width, width2;
        int any_rebase;
};

int add_remote_to_show_info(struct string_list_item *item, void *cb_data)
{
        struct show_info *info = cb_data;
        int n = strlen(item->string);
        if (n > info->width)
                info->width = n;
        string_list_insert(item->string, info->list);
        return 0;
}

int show_remote_info_item(struct string_list_item *item, void *cb_data)
{
        struct show_info *info = cb_data;
        struct ref_states *states = info->states;
        const char *name = item->string;

        if (states->queried) {
                const char *fmt = "%s";
                const char *arg = "";
                if (string_list_has_string(&states->new, name)) {
                        fmt = " new (next fetch will store in remotes/%s)";
                        arg = states->remote->name;
                } else if (string_list_has_string(&states->tracked, name))
                        arg = " tracked";
                else if (string_list_has_string(&states->stale, name))
                        arg = " stale (use 'git remote prune' to remove)";
                else
                        arg = " ???";
                printf("    %-*s", info->width, name);
                printf(fmt, arg);
                printf("\n");
        } else
                printf("    %s\n", name);

        return 0;
}

int add_local_to_show_info(struct string_list_item *branch_item, void *cb_data)
{
        struct show_info *show_info = cb_data;
        struct ref_states *states = show_info->states;
        struct branch_info *branch_info = branch_item->util;
        struct string_list_item *item;
        int n;

        if (!branch_info->merge.nr || !branch_info->remote_name ||
            strcmp(states->remote->name, branch_info->remote_name))
                return 0;
        if ((n = strlen(branch_item->string)) > show_info->width)
                show_info->width = n;
        if (branch_info->rebase)
                show_info->any_rebase = 1;

        item = string_list_insert(branch_item->string, show_info->list);
        item->util = branch_info;

        return 0;
}

int show_local_info_item(struct string_list_item *item, void *cb_data)
{
        struct show_info *show_info = cb_data;
        struct branch_info *branch_info = item->util;
        struct string_list *merge = &branch_info->merge;
        const char *also;
        int i;

        if (branch_info->rebase && branch_info->merge.nr > 1) {
                error("invalid branch.%s.merge; cannot rebase onto > 1 branch",
                        item->string);
                return 0;
        }

        printf("    %-*s ", show_info->width, item->string);
        if (branch_info->rebase) {
                printf("rebases onto remote %s\n", merge->items[0].string);
                return 0;
        } else if (show_info->any_rebase) {
                printf(" merges with remote %s\n", merge->items[0].string);
                also = "    and with remote";
        } else {
                printf("merges with remote %s\n", merge->items[0].string);
                also = "   and with remote";
        }
        for (i = 1; i < merge->nr; i++)
                printf("    %-*s %s %s\n", show_info->width, "", also,
                       merge->items[i].string);

        return 0;
}

int add_push_to_show_info(struct string_list_item *push_item, void *cb_data)
{
        struct show_info *show_info = cb_data;
        struct push_info *push_info = push_item->util;
        struct string_list_item *item;
        int n;
        if ((n = strlen(push_item->string)) > show_info->width)
                show_info->width = n;
        if ((n = strlen(push_info->dest)) > show_info->width2)
                show_info->width2 = n;
        item = string_list_append(push_item->string, show_info->list);
        item->util = push_item->util;
        return 0;
}

int show_push_info_item(struct string_list_item *item, void *cb_data)
{
        struct show_info *show_info = cb_data;
        struct push_info *push_info = item->util;
        char *src = item->string, *status = NULL;

        switch (push_info->status) {
        case PUSH_STATUS_CREATE:
                status = "create";
                break;
        case PUSH_STATUS_DELETE:
                status = "delete";
                src = "(none)";
                break;
        case PUSH_STATUS_UPTODATE:
                status = "up to date";
                break;
        case PUSH_STATUS_FASTFORWARD:
                status = "fast forwardable";
                break;
        case PUSH_STATUS_OUTOFDATE:
                status = "local out of date";
                break;
        case PUSH_STATUS_NOTQUERIED:
                break;
        }
        if (status)
                printf("    %-*s %s to %-*s (%s)\n", show_info->width, src,
                        push_info->forced ? "forces" : "pushes",
                        show_info->width2, push_info->dest, status);
        else
                printf("    %-*s %s to %s\n", show_info->width, src,
                        push_info->forced ? "forces" : "pushes",
                        push_info->dest);
        return 0;
}

static int show(int argc, const char **argv)
{
        int no_query = 0, result = 0, query_flag = 0;
        struct option options[] = {
                OPT_GROUP("show specific options"),
                OPT_BOOLEAN('n', NULL, &no_query, "do not query remotes"),
                OPT_END()
        };
        struct ref_states states;
        struct string_list info_list = { NULL, 0, 0, 0 };
        struct show_info info;

        argc = parse_options(argc, argv, options, builtin_remote_usage, 0);

        if (argc < 1)
                return show_all();

        if (!no_query)
                query_flag = (GET_REF_STATES | GET_HEAD_NAMES | GET_PUSH_REF_STATES);

        memset(&states, 0, sizeof(states));
        memset(&info, 0, sizeof(info));
        info.states = &states;
        info.list = &info_list;
        for (; argc; argc--, argv++) {
                int i;

                get_remote_ref_states(*argv, &states, query_flag);

                printf("* remote %s\n  URL: %s\n", *argv,
                        states.remote->url_nr > 0 ?
                                states.remote->url[0] : "(no URL)");
                if (no_query)
                        printf("  HEAD branch: (not queried)\n");
                else if (!states.heads.nr)
                        printf("  HEAD branch: (unknown)\n");
                else if (states.heads.nr == 1)
                        printf("  HEAD branch: %s\n", states.heads.items[0].string);
                else {
                        printf("  HEAD branch (remote HEAD is ambiguous,"
                               " may be one of the following):\n");
                        for (i = 0; i < states.heads.nr; i++)
                                printf("    %s\n", states.heads.items[i].string);
                }

                /* remote branch info */
                info.width = 0;
                for_each_string_list(add_remote_to_show_info, &states.new, &info);
                for_each_string_list(add_remote_to_show_info, &states.tracked, &info);
                for_each_string_list(add_remote_to_show_info, &states.stale, &info);
                if (info.list->nr)
                        printf("  Remote branch%s:%s\n",
                               info.list->nr > 1 ? "es" : "",
                                no_query ? " (status not queried)" : "");
                for_each_string_list(show_remote_info_item, info.list, &info);
                string_list_clear(info.list, 0);

                /* git pull info */
                info.width = 0;
                info.any_rebase = 0;
                for_each_string_list(add_local_to_show_info, &branch_list, &info);
                if (info.list->nr)
                        printf("  Local branch%s configured for 'git pull':\n",
                               info.list->nr > 1 ? "es" : "");
                for_each_string_list(show_local_info_item, info.list, &info);
                string_list_clear(info.list, 0);

                /* git push info */
                if (states.remote->mirror)
                        printf("  Local refs will be mirrored by 'git push'\n");

                info.width = info.width2 = 0;
                for_each_string_list(add_push_to_show_info, &states.push, &info);
                sort_string_list(info.list);
                if (info.list->nr)
                        printf("  Local ref%s configured for 'git push'%s:\n",
                                info.list->nr > 1 ? "s" : "",
                                no_query ? " (status not queried)" : "");
                for_each_string_list(show_push_info_item, info.list, &info);
                string_list_clear(info.list, 0);

                free_remote_ref_states(&states);
        }

        return result;
}

static int set_head(int argc, const char **argv)
{
        int i, opt_a = 0, opt_d = 0, result = 0;
        struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT;
        char *head_name = NULL;

        struct option options[] = {
                OPT_GROUP("set-head specific options"),
                OPT_BOOLEAN('a', "auto", &opt_a,
                            "set refs/remotes/<name>/HEAD according to remote"),
                OPT_BOOLEAN('d', "delete", &opt_d,
                            "delete refs/remotes/<name>/HEAD"),
                OPT_END()
        };
        argc = parse_options(argc, argv, options, builtin_remote_usage, 0);
        if (argc)
                strbuf_addf(&buf, "refs/remotes/%s/HEAD", argv[0]);

        if (!opt_a && !opt_d && argc == 2) {
                head_name = xstrdup(argv[1]);
        } else if (opt_a && !opt_d && argc == 1) {
                struct ref_states states;
                memset(&states, 0, sizeof(states));
                get_remote_ref_states(argv[0], &states, GET_HEAD_NAMES);
                if (!states.heads.nr)
                        result |= error("Cannot determine remote HEAD");
                else if (states.heads.nr > 1) {
                        result |= error("Multiple remote HEAD branches. "
                                        "Please choose one explicitly with:");
                        for (i = 0; i < states.heads.nr; i++)
                                fprintf(stderr, "  git remote set-head %s %s\n",
                                        argv[0], states.heads.items[i].string);
                } else
                        head_name = xstrdup(states.heads.items[0].string);
                free_remote_ref_states(&states);
        } else if (opt_d && !opt_a && argc == 1) {
                if (delete_ref(buf.buf, NULL, REF_NODEREF))
                        result |= error("Could not delete %s", buf.buf);
        } else
                usage_with_options(builtin_remote_usage, options);

        if (head_name) {
                unsigned char sha1[20];
                strbuf_addf(&buf2, "refs/remotes/%s/%s", argv[0], head_name);
                /* make sure it's valid */
                if (!resolve_ref(buf2.buf, sha1, 1, NULL))
                        result |= error("Not a valid ref: %s", buf2.buf);
                else if (create_symref(buf.buf, buf2.buf, "remote set-head"))
                        result |= error("Could not setup %s", buf.buf);
                if (opt_a)
                        printf("%s/HEAD set to %s\n", argv[0], head_name);
                free(head_name);
        }

        strbuf_release(&buf);
        strbuf_release(&buf2);
        return result;
}

static int prune(int argc, const char **argv)
{
        int dry_run = 0, result = 0;
        struct option options[] = {
                OPT_GROUP("prune specific options"),
                OPT__DRY_RUN(&dry_run),
                OPT_END()
        };
        struct ref_states states;
        const char *dangling_msg;

        argc = parse_options(argc, argv, options, builtin_remote_usage, 0);

        if (argc < 1)
                usage_with_options(builtin_remote_usage, options);

        dangling_msg = (dry_run
                        ? " %s will become dangling!\n"
                        : " %s has become dangling!\n");

        memset(&states, 0, sizeof(states));
        for (; argc; argc--, argv++) {
                int i;

                get_remote_ref_states(*argv, &states, GET_REF_STATES);

                if (states.stale.nr) {
                        printf("Pruning %s\n", *argv);
                        printf("URL: %s\n",
                               states.remote->url_nr
                               ? states.remote->url[0]
                               : "(no URL)");
                }

                for (i = 0; i < states.stale.nr; i++) {
                        const char *refname = states.stale.items[i].util;

                        if (!dry_run)
                                result |= delete_ref(refname, NULL, 0);

                        printf(" * [%s] %s\n", dry_run ? "would prune" : "pruned",
                               abbrev_ref(refname, "refs/remotes/"));
                        warn_dangling_symref(dangling_msg, refname);
                }

                free_remote_ref_states(&states);
        }

        return result;
}

static int get_one_remote_for_update(struct remote *remote, void *priv)
{
        struct string_list *list = priv;
        if (!remote->skip_default_update)
                string_list_append(remote->name, list);
        return 0;
}

struct remote_group {
        const char *name;
        struct string_list *list;
} remote_group;

static int get_remote_group(const char *key, const char *value, void *cb)
{
        if (!prefixcmp(key, "remotes.") &&
                        !strcmp(key + 8, remote_group.name)) {
                /* split list by white space */
                int space = strcspn(value, " \t\n");
                while (*value) {
                        if (space > 1)
                                string_list_append(xstrndup(value, space),
                                                remote_group.list);
                        value += space + (value[space] != '\0');
                        space = strcspn(value, " \t\n");
                }
        }

        return 0;
}

static int update(int argc, const char **argv)
{
        int i, result = 0;
        struct string_list list = { NULL, 0, 0, 0 };
        static const char *default_argv[] = { NULL, "default", NULL };

        if (argc < 2) {
                argc = 2;
                argv = default_argv;
        }

        remote_group.list = &list;
        for (i = 1; i < argc; i++) {
                remote_group.name = argv[i];
                result = git_config(get_remote_group, NULL);
        }

        if (!result && !list.nr  && argc == 2 && !strcmp(argv[1], "default"))
                result = for_each_remote(get_one_remote_for_update, &list);

        for (i = 0; i < list.nr; i++)
                result |= fetch_remote(list.items[i].string);

        /* all names were strdup()ed or strndup()ed */
        list.strdup_strings = 1;
        string_list_clear(&list, 0);

        return result;
}

static int get_one_entry(struct remote *remote, void *priv)
{
        struct string_list *list = priv;

        if (remote->url_nr > 0) {
                int i;

                for (i = 0; i < remote->url_nr; i++)
                        string_list_append(remote->name, list)->util = (void *)remote->url[i];
        } else
                string_list_append(remote->name, list)->util = NULL;

        return 0;
}

static int show_all(void)
{
        struct string_list list = { NULL, 0, 0 };
        int result = for_each_remote(get_one_entry, &list);

        if (!result) {
                int i;

                sort_string_list(&list);
                for (i = 0; i < list.nr; i++) {
                        struct string_list_item *item = list.items + i;
                        if (verbose)
                                printf("%s\t%s\n", item->string,
                                        item->util ? (const char *)item->util : "");
                        else {
                                if (i && !strcmp((item - 1)->string, item->string))
                                        continue;
                                printf("%s\n", item->string);
                        }
                }
        }
        return result;
}

int cmd_remote(int argc, const char **argv, const char *prefix)
{
        struct option options[] = {
                OPT__VERBOSE(&verbose),
                OPT_END()
        };
        int result;

        argc = parse_options(argc, argv, options, builtin_remote_usage,
                PARSE_OPT_STOP_AT_NON_OPTION);

        if (argc < 1)
                result = show_all();
        else if (!strcmp(argv[0], "add"))
                result = add(argc, argv);
        else if (!strcmp(argv[0], "rename"))
                result = mv(argc, argv);
        else if (!strcmp(argv[0], "rm"))
                result = rm(argc, argv);
        else if (!strcmp(argv[0], "set-head"))
                result = set_head(argc, argv);
        else if (!strcmp(argv[0], "show"))
                result = show(argc, argv);
        else if (!strcmp(argv[0], "prune"))
                result = prune(argc, argv);
        else if (!strcmp(argv[0], "update"))
                result = update(argc, argv);
        else {
                error("Unknown subcommand: %s", argv[0]);
                usage_with_options(builtin_remote_usage, options);
        }

        return result ? 1 : 0;
}