create extension if not exists btree_gin;

create table accounts (
    id serial not null primary key,
    name text not null,
    email text not null,
    settings jsonb not null
    -- настройки: replyto, cc, bcc, imap, smtp, folders
);
create unique index accounts_email on accounts (email);

create table folders (
    id serial not null primary key,
    uidvalidity int not null,
    account_id int not null,
    name text not null,
    highestmodseq int not null default 0,
    kind text not null,
    foreign key (account_id) references accounts (id) on delete cascade on update cascade
);
create unique index folders_name on folders (account_id, name);

-- Очередь команд. Виды команд:
-- 1) пометить сообщение
-- 2) переместить сообщение
-- 3) удалить сообщение
-- 4) отправить черновик
create table command_queue (
    id serial not null primary key,
    account_id int not null,
    folder_id int,
    uid int,
    props jsonb not null
);

-- Ещё нигде не сохранённые черновики сообщений
create table drafts (
    id serial not null primary key,
    time bigint not null,
    props jsonb not null
);

create table messages (
    id serial not null primary key,
    thread_id int,
    folder_id int not null,
    uid int,
    messageid text not null,
    inreplyto text not null,
    refs text[] not null,
    subject text not null,
    props jsonb not null,
    body_html text not null default '',
    body_text text not null default '',
    body_html_text text not null default '',
    -- FIXME bigint
    time timestamptz not null,
    size int not null,
    -- FIXME jsonb
    flags text[] not null,
    foreign key (folder_id) references folders (id) on delete cascade on update cascade
);
create unique index messages_unique on messages (folder_id, uid);
create index messages_flags on messages using gin (folder_id, flags);
create index messages_messageid on messages (messageid);
create index messages_refs on messages using gin (refs);
create index messages_folder_id_time on messages (folder_id, time);
create index messages_time on messages (time);
-- create or replace function immutable_year(d timestamptz) returns text
-- language plpgsql immutable as $$
-- begin
--     return date_part('year', d);
-- end
-- $$;
-- create index messages_year on messages (immutable_year(time));
create or replace function messages_fulltext(msg messages) returns tsvector
language plpgsql immutable as $$
begin
    return setweight(to_tsvector('russian', regexp_replace(
        coalesce(msg.props->>'from', '') || ' ' ||
        coalesce(msg.props->>'replyto', '') || ' ' ||
        coalesce(msg.props->>'to', '') || ' ' ||
        coalesce(msg.props->>'cc', '') || ' ' ||
        coalesce(msg.props->>'bcc', '') || ' ' ||
        coalesce(msg.props->>'attachments', '') || ' ' ||
        msg.subject,
        '\W+', ' ', 'g'
    )), 'A')
    || setweight(to_tsvector('russian', msg.body_html_text || ' ' || msg.body_text), 'B');
end
$$;
create index messages_text on messages using gin (messages_fulltext(messages));

create table threads (
    id serial not null primary key,
    first_msg int,
    msg_count int not null default 1,
    foreign key (first_msg) references messages (id) on delete restrict on update cascade
);
create index threads_first_msg on threads (first_msg);

alter table messages add foreign key (thread_id) references threads (id) on delete restrict on update cascade;

alter table accounts owner to operetta;
alter table folders owner to operetta;
alter table messages owner to operetta;
alter table threads owner to operetta;