PRAGMA journal_mode=WAL;

CREATE TABLE IF NOT EXISTS users
(
    id            INTEGER PRIMARY KEY AUTOINCREMENT,
    name          TEXT NOT NULL,
    public_key    TEXT NOT NULL,
    creation_time DATETIME DEFAULT CURRENT_TIMESTAMP
);

CREATE TABLE IF NOT EXISTS security_types
(
    name TEXT PRIMARY KEY
) STRICT;

INSERT INTO security_types(name)
VALUES ('currency'),
       ('bond');

CREATE TABLE IF NOT EXISTS securities
(
    id            INTEGER PRIMARY KEY AUTOINCREMENT,
    security_type TEXT NOT NULL,
    name          TEXT NOT NULL UNIQUE,
    symbol        TEXT NOT NULL UNIQUE,
    creation_time DATETIME DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (security_type) REFERENCES security_types (name)
);

CREATE TABLE IF NOT EXISTS account_types
(
    name TEXT PRIMARY KEY
) STRICT;

INSERT INTO account_types(name)
VALUES ('checking'),
       ('security_emitter');

CREATE TABLE IF NOT EXISTS accounts
(
    id            INTEGER PRIMARY KEY AUTOINCREMENT,
    version       INTEGER  NOT NULL CHECK ( version >= 0 ),
    security      INTEGER  NOT NULL,
    account_type  TEXT     NOT NULL,

    amount        INTEGER  NOT NULL,
    timestamp     DATETIME NOT NULL,
    creation_time DATETIME DEFAULT CURRENT_TIMESTAMP,

    FOREIGN KEY (security) REFERENCES securities (id),
    FOREIGN KEY (account_type) REFERENCES account_types (name)
);

CREATE TABLE IF NOT EXISTS accounts_history
(
    account_id      INTEGER  NOT NULL,
    account_version INTEGER  NOT NULL,
    amount          INTEGER  NOT NULL,
    timestamp       DATETIME NOT NULL,
    FOREIGN KEY (account_id) REFERENCES accounts (id),
    PRIMARY KEY (account_id, account_version)
);

CREATE TABLE IF NOT EXISTS account_user_permissions
(
    id            INTEGER PRIMARY KEY AUTOINCREMENT,
    account_id    INTEGER NOT NULL,
    user_id       INTEGER NOT NULL,
    creation_time DATETIME DEFAULT CURRENT_TIMESTAMP,

    FOREIGN KEY (account_id) REFERENCES accounts (id),
    FOREIGN KEY (user_id) REFERENCES users (id)

);

CREATE TABLE IF NOT EXISTS cashed_cheques
(
    id                     INTEGER PRIMARY KEY AUTOINCREMENT,
    drawer_user_id         INTEGER NOT NULL,
    drawer_account_id      INTEGER NOT NULL,
    drawer_account_version INTEGER NOT NULL,
    cheque_number          INTEGER NOT NULL,
    amount                 INTEGER NOT NULL,
    underlying_security    INTEGER NOT NULL,
    payee_user_id          INTEGER NOT NULL,
    payee_account_id       INTEGER NOT NULL,
    payee_account_version  INTEGER NOT NULL,
    creation_time          DATETIME DEFAULT CURRENT_TIMESTAMP,

    FOREIGN KEY (underlying_security) REFERENCES securities (id),
    FOREIGN KEY (drawer_user_id) REFERENCES users (id),
    FOREIGN KEY (drawer_account_id) REFERENCES accounts (id),
    FOREIGN KEY (payee_user_id) REFERENCES users (id),
    FOREIGN KEY (payee_account_id) REFERENCES accounts (id),
    CONSTRAINT double_spending UNIQUE (drawer_user_id, cheque_number) -- no double spending
);