-- The consolidated schema, through migration 0002: what a fresh database is given at once (the mesh's rule: a
-- numbered migration for the running store, and this for a fresh install).
create table mail_group (
    id      bigserial   primary key,
    label   text        not null unique default '',
    created timestamptz not null default now());

create table mail_entry (
    id             bigserial   primary key,
    account        text        not null,
    message_id     text        not null default '',
    folder         text        not null,
    uidvalidity    bigint      not null default 0,
    uid            bigint      not null default 0,
    message_key    text        not null default '',
    date           timestamptz not null,
    sender_name    text        not null default '',
    sender_address text        not null default '',
    subject        text        not null default '',
    mail_group     bigint      references mail_group (id),
    summary        text        not null default '' check (char_length(summary) <= 160),
    mark           text        check (mark is null or mark in ('matters', 'scam warning', 'neither')),
    why            text        not null default '',
    due_date       date,
    told           boolean     not null default false,
    judged         timestamptz not null default now(),
    constraint mail_entry_one_per_message unique (account, message_key));
create index mail_entry_account_date on mail_entry (account, date desc);
create index mail_entry_judged on mail_entry (judged);

-- A reading lesson (novox/hq ADR 0459 §8, §9, issue 1428): the corrected mail's own headers (never a body),
-- the change made, when, and whether it was undone. sender_address and mail_group are its own matching keys
-- for the next batch's question (1427): a lesson matches a mail of the same sender, or already known to be
-- of the same mail group.
create table reading_lesson (
    id             bigserial   primary key,
    account        text        not null default '',
    folder         text        not null default '',
    sender_name    text        not null default '',
    sender_address text        not null default '',
    subject        text        not null default '',
    mail_group     bigint      references mail_group (id),
    change         text        not null default '',
    made           timestamptz not null default now(),
    undone         boolean     not null default false);
create index reading_lesson_sender on reading_lesson (sender_address);

-- Heard but not yet read (novox/hq ADR 0459 §3, §12, issue 1518): headers only, kept until reading takes them,
-- in the order they were heard (id, a bigserial, orders arrival regardless of the mail's own date). A mail
-- heard twice is kept once: by its account, folder, UIDVALIDITY and UID, and by its account and message key
-- (issue 1849: its Message-ID, else its folder, UIDVALIDITY and UID), so one Gmail message heard in INBOX and
-- in All Mail waits once.
create table waiting_mail (
    id          bigserial   primary key,
    account     text        not null,
    folder      text        not null,
    message_id  text        not null default '',
    message_key text        not null default '',
    uidvalidity bigint      not null default 0,
    uid         bigint      not null default 0,
    date        timestamptz not null,
    sender      jsonb       not null default '[]',
    subject     text        not null default '',
    flags       text[]      not null default '{}',
    size        bigint      not null default 0,
    heard       timestamptz not null default now(),
    unique (account, folder, uidvalidity, uid),
    constraint waiting_mail_one_per_message unique (account, message_key));

-- The reader's own health (novox/hq ADR 0459 §12, issue 1519), kept across a restart: one row, singleton by
-- its fixed id. cause is "" while healthy, else one of refused, timed out, out of shape; since is the first
-- failure's own time, not the latest one.
create table reader_health (
    id      smallint    primary key default 1,
    healthy boolean     not null default true,
    cause   text        not null default '',
    why     text        not null default '',
    since   timestamptz,
    constraint reader_health_singleton check (id = 1));