-- ============================================================
--  Родословное дерево семьи — SQL-схема (PostgreSQL 15+)
-- ============================================================
-- Кодировка UTF-8. Запуск: psql -U postgres -d family_tree -f schema.sql

CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
CREATE EXTENSION IF NOT EXISTS "pg_trgm";   -- быстрый поиск по имени/фамилии

-- ---------- Пользователи и роли ----------
CREATE TYPE user_role AS ENUM ('admin', 'editor', 'viewer');

CREATE TABLE users (
    id            UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    email         TEXT NOT NULL UNIQUE,
    password_hash TEXT NOT NULL,
    display_name  TEXT NOT NULL,
    role          user_role NOT NULL DEFAULT 'viewer',
    created_at    TIMESTAMPTZ NOT NULL DEFAULT now(),
    updated_at    TIMESTAMPTZ NOT NULL DEFAULT now()
);

-- ---------- Персоны ----------
CREATE TYPE gender_t AS ENUM ('male', 'female', 'other');

CREATE TABLE persons (
    id           UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    first_name   TEXT NOT NULL,
    last_name    TEXT,
    middle_name  TEXT,
    gender       gender_t NOT NULL DEFAULT 'other',
    birth_date   DATE,
    death_date   DATE,
    birth_place  TEXT,
    photo_url    TEXT,
    bio          TEXT,
    contacts     TEXT,
    notes        TEXT,
    context      TEXT,           -- произвольный дополнительный контекст
    resource_url TEXT,           -- ссылка на подробный внешний ресурс
    created_by   UUID REFERENCES users(id) ON DELETE SET NULL,
    created_at   TIMESTAMPTZ NOT NULL DEFAULT now(),
    updated_at   TIMESTAMPTZ NOT NULL DEFAULT now()
);

CREATE INDEX idx_persons_last_name  ON persons USING gin (last_name gin_trgm_ops);
CREATE INDEX idx_persons_first_name ON persons USING gin (first_name gin_trgm_ops);

-- ---------- Связь родитель → ребёнок (вкл. приёмные) ----------
CREATE TYPE parent_kind AS ENUM ('biological', 'adoptive', 'step', 'guardian');

CREATE TABLE parent_child (
    id         UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    parent_id  UUID NOT NULL REFERENCES persons(id) ON DELETE CASCADE,
    child_id   UUID NOT NULL REFERENCES persons(id) ON DELETE CASCADE,
    kind       parent_kind NOT NULL DEFAULT 'biological',
    UNIQUE (parent_id, child_id),
    CHECK (parent_id <> child_id)
);
CREATE INDEX idx_pc_parent ON parent_child(parent_id);
CREATE INDEX idx_pc_child  ON parent_child(child_id);

-- ---------- Браки / партнёрства (несколько браков поддерживаются) ----------
CREATE TYPE union_status AS ENUM ('married', 'divorced', 'partner', 'widowed');

CREATE TABLE unions (
    id          UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    partner_a   UUID NOT NULL REFERENCES persons(id) ON DELETE CASCADE,
    partner_b   UUID NOT NULL REFERENCES persons(id) ON DELETE CASCADE,
    status      union_status NOT NULL DEFAULT 'married',
    start_date  DATE,
    end_date    DATE,
    UNIQUE (partner_a, partner_b),
    CHECK (partner_a <> partner_b)
);

-- ---------- Галерея фотографий ----------
CREATE TABLE media (
    id         UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    person_id  UUID NOT NULL REFERENCES persons(id) ON DELETE CASCADE,
    url        TEXT NOT NULL,
    caption    TEXT,
    sort_order INT NOT NULL DEFAULT 0,
    created_at TIMESTAMPTZ NOT NULL DEFAULT now()
);
CREATE INDEX idx_media_person ON media(person_id);

-- ---------- История изменений (аудит) ----------
CREATE TABLE change_log (
    id         BIGSERIAL PRIMARY KEY,
    user_id    UUID REFERENCES users(id) ON DELETE SET NULL,
    entity     TEXT NOT NULL,         -- 'person' | 'union' | 'parent_child' | ...
    entity_id  UUID,
    action     TEXT NOT NULL,         -- 'create' | 'update' | 'delete'
    diff       JSONB,                 -- было/стало
    created_at TIMESTAMPTZ NOT NULL DEFAULT now()
);
CREATE INDEX idx_log_entity ON change_log(entity, entity_id);

-- ---------- Авто-обновление updated_at ----------
CREATE OR REPLACE FUNCTION touch_updated_at() RETURNS trigger AS $$
BEGIN NEW.updated_at = now(); RETURN NEW; END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER trg_persons_touch BEFORE UPDATE ON persons
    FOR EACH ROW EXECUTE FUNCTION touch_updated_at();
CREATE TRIGGER trg_users_touch BEFORE UPDATE ON users
    FOR EACH ROW EXECUTE FUNCTION touch_updated_at();

-- ---------- Удобное представление дерева ----------
CREATE VIEW person_relations AS
SELECT p.id,
       p.first_name, p.last_name, p.middle_name, p.gender,
       p.birth_date, p.death_date,
       (SELECT array_agg(pc.parent_id) FROM parent_child pc WHERE pc.child_id = p.id)  AS parent_ids,
       (SELECT array_agg(pc.child_id)  FROM parent_child pc WHERE pc.parent_id = p.id) AS child_ids,
       (SELECT array_agg(CASE WHEN u.partner_a = p.id THEN u.partner_b ELSE u.partner_a END)
          FROM unions u WHERE u.partner_a = p.id OR u.partner_b = p.id)                AS spouse_ids
FROM persons p;