CREATE EXTENSION IF NOT EXISTS "uuid-ossp";

CREATE TYPE "QuantityUnit" AS ENUM (
    'g',
    'dkg',
    'kg',
    'piece'
    );

CREATE TABLE photos
(
    id          serial                                 NOT NULL PRIMARY KEY,
    local_path  character varying                      NOT NULL,
    file_name   character varying                      NOT NULL,
    unique_name text DEFAULT (gen_random_uuid())::text NOT NULL
);

CREATE TABLE products
(
    id                serial              NOT NULL PRIMARY KEY,
    "name"            character varying   NOT NULL,
    category          character varying,
    deliver_days_flag integer DEFAULT 127 NOT NULL
);

CREATE TABLE product_variants
(
    id                serial                                             NOT NULL PRIMARY KEY,
    product_id        integer REFERENCES products (id) ON DELETE CASCADE NOT NULL,
    "name"            character varying                                  NOT NULL,
    short_description character varying                                  NOT NULL,
    long_description  character varying                                  NOT NULL,
    price             integer                                            NOT NULL,
    quantity_unit     "QuantityUnit"                                     NOT NULL,
    CONSTRAINT non_negative CHECK ((price >= 0))
);

CREATE TABLE stocks
(
    id                 serial                                                     NOT NULL PRIMARY KEY,
    product_variant_id integer REFERENCES product_variants (id) ON DELETE CASCADE NOT NULL,
    quantity           integer DEFAULT 0                                          NOT NULL,
    quantity_unit      "QuantityUnit"                                             NOT NULL,
    CONSTRAINT positive_quantity CHECK ((quantity >= 0))
);

CREATE TABLE product_photos
(
    id                 serial                                                     NOT NULL PRIMARY KEY,
    product_variant_id integer REFERENCES product_variants (id) ON DELETE CASCADE NOT NULL,
    photo_id           integer REFERENCES photos (id)                             NOT NULL
);

CREATE TABLE categories
(
    id        serial  NOT NULL PRIMARY KEY,
    parent_id int references categories (id) ON DELETE CASCADE,
    "name"    varchar not null,
    "key"     varchar not null,
    "svg"     varchar not null
);