#include "cache.h"
#include "commit.h"
#include "refs.h"
#include "notes-utils.h"

void create_notes_commit(struct notes_tree *t, struct commit_list *parents,
                         const char *msg, size_t msg_len,
                         unsigned char *result_sha1)
{
        unsigned char tree_sha1[20];

        assert(t->initialized);

        if (write_notes_tree(t, tree_sha1))
                die("Failed to write notes tree to database");

        if (!parents) {
                /* Deduce parent commit from t->ref */
                unsigned char parent_sha1[20];
                if (!read_ref(t->ref, parent_sha1)) {
                        struct commit *parent = lookup_commit(parent_sha1);
                        if (parse_commit(parent))
                                die("Failed to find/parse commit %s", t->ref);
                        commit_list_insert(parent, &parents);
                }
                /* else: t->ref points to nothing, assume root/orphan commit */
        }

        if (commit_tree(msg, msg_len, tree_sha1, parents, result_sha1, NULL, NULL))
                die("Failed to commit notes tree to database");
}

void commit_notes(struct notes_tree *t, const char *msg)
{
        struct strbuf buf = STRBUF_INIT;
        unsigned char commit_sha1[20];

        if (!t)
                t = &default_notes_tree;
        if (!t->initialized || !t->update_ref || !*t->update_ref)
                die(_("Cannot commit uninitialized/unreferenced notes tree"));
        if (!t->dirty)
                return; /* don't have to commit an unchanged tree */

        /* Prepare commit message and reflog message */
        strbuf_addstr(&buf, msg);
        strbuf_complete_line(&buf);

        create_notes_commit(t, NULL, buf.buf, buf.len, commit_sha1);
        strbuf_insert(&buf, 0, "notes: ", 7); /* commit message starts at index 7 */
        update_ref(buf.buf, t->update_ref, commit_sha1, NULL, 0,
                   UPDATE_REFS_DIE_ON_ERR);

        strbuf_release(&buf);
}

int parse_notes_merge_strategy(const char *v, enum notes_merge_strategy *s)
{
        if (!strcmp(v, "manual"))
                *s = NOTES_MERGE_RESOLVE_MANUAL;
        else if (!strcmp(v, "ours"))
                *s = NOTES_MERGE_RESOLVE_OURS;
        else if (!strcmp(v, "theirs"))
                *s = NOTES_MERGE_RESOLVE_THEIRS;
        else if (!strcmp(v, "union"))
                *s = NOTES_MERGE_RESOLVE_UNION;
        else if (!strcmp(v, "cat_sort_uniq"))
                *s = NOTES_MERGE_RESOLVE_CAT_SORT_UNIQ;
        else
                return -1;

        return 0;
}

static combine_notes_fn parse_combine_notes_fn(const char *v)
{
        if (!strcasecmp(v, "overwrite"))
                return combine_notes_overwrite;
        else if (!strcasecmp(v, "ignore"))
                return combine_notes_ignore;
        else if (!strcasecmp(v, "concatenate"))
                return combine_notes_concatenate;
        else if (!strcasecmp(v, "cat_sort_uniq"))
                return combine_notes_cat_sort_uniq;
        else
                return NULL;
}

static int notes_rewrite_config(const char *k, const char *v, void *cb)
{
        struct notes_rewrite_cfg *c = cb;
        if (starts_with(k, "notes.rewrite.") && !strcmp(k+14, c->cmd)) {
                c->enabled = git_config_bool(k, v);
                return 0;
        } else if (!c->mode_from_env && !strcmp(k, "notes.rewritemode")) {
                if (!v)
                        return config_error_nonbool(k);
                c->combine = parse_combine_notes_fn(v);
                if (!c->combine) {
                        error(_("Bad notes.rewriteMode value: '%s'"), v);
                        return 1;
                }
                return 0;
        } else if (!c->refs_from_env && !strcmp(k, "notes.rewriteref")) {
                /* note that a refs/ prefix is implied in the
                 * underlying for_each_glob_ref */
                if (starts_with(v, "refs/notes/"))
                        string_list_add_refs_by_glob(c->refs, v);
                else
                        warning(_("Refusing to rewrite notes in %s"
                                " (outside of refs/notes/)"), v);
                return 0;
        }

        return 0;
}


struct notes_rewrite_cfg *init_copy_notes_for_rewrite(const char *cmd)
{
        struct notes_rewrite_cfg *c = xmalloc(sizeof(struct notes_rewrite_cfg));
        const char *rewrite_mode_env = getenv(GIT_NOTES_REWRITE_MODE_ENVIRONMENT);
        const char *rewrite_refs_env = getenv(GIT_NOTES_REWRITE_REF_ENVIRONMENT);
        c->cmd = cmd;
        c->enabled = 1;
        c->combine = combine_notes_concatenate;
        c->refs = xcalloc(1, sizeof(struct string_list));
        c->refs->strdup_strings = 1;
        c->refs_from_env = 0;
        c->mode_from_env = 0;
        if (rewrite_mode_env) {
                c->mode_from_env = 1;
                c->combine = parse_combine_notes_fn(rewrite_mode_env);
                if (!c->combine)
                        /* TRANSLATORS: The first %s is the name of the
                           environment variable, the second %s is its value */
                        error(_("Bad %s value: '%s'"), GIT_NOTES_REWRITE_MODE_ENVIRONMENT,
                                        rewrite_mode_env);
        }
        if (rewrite_refs_env) {
                c->refs_from_env = 1;
                string_list_add_refs_from_colon_sep(c->refs, rewrite_refs_env);
        }
        git_config(notes_rewrite_config, c);
        if (!c->enabled || !c->refs->nr) {
                string_list_clear(c->refs, 0);
                free(c->refs);
                free(c);
                return NULL;
        }
        c->trees = load_notes_trees(c->refs, NOTES_INIT_WRITABLE);
        string_list_clear(c->refs, 0);
        free(c->refs);
        return c;
}

int copy_note_for_rewrite(struct notes_rewrite_cfg *c,
                          const unsigned char *from_obj, const unsigned char *to_obj)
{
        int ret = 0;
        int i;
        for (i = 0; c->trees[i]; i++)
                ret = copy_note(c->trees[i], from_obj, to_obj, 1, c->combine) || ret;
        return ret;
}

void finish_copy_notes_for_rewrite(struct notes_rewrite_cfg *c, const char *msg)
{
        int i;
        for (i = 0; c->trees[i]; i++) {
                commit_notes(c->trees[i], msg);
                free_notes(c->trees[i]);
        }
        free(c->trees);
        free(c);
}