CREATE DATABASE IF NOT EXISTS argent_shard_01
CHARACTER SET utf8mb4 COLLATE utf8mb4_uca1400_ai_ci;
USE argent_shard_01;

CREATE TABLE ledger_statuses (
    status_id TINYINT PRIMARY KEY,
    name VARCHAR(20) UNIQUE NOT NULL
) ENGINE=InnoDB;

CREATE TABLE ledger_entry_types (
    type_id TINYINT PRIMARY KEY,
    name VARCHAR(20) UNIQUE NOT NULL
) ENGINE=InnoDB;

CREATE TABLE ledger (
    entry_id BINARY(16) NOT NULL,
    batch_id BINARY(16) NOT NULL,
    user_id BINARY(16) NOT NULL,
    group_id BINARY(16) DEFAULT NULL,
    amount DECIMAL(15, 2) NOT NULL,
    currency_code CHAR(3) NOT NULL,
    description VARCHAR(255),
    status_id TINYINT DEFAULT 1,
    type_id TINYINT NOT NULL,
    created_at DATETIME NOT NULL,
    PRIMARY KEY (user_id, entry_id),
    FOREIGN KEY (status_id) REFERENCES ledger_statuses(status_id),
    FOREIGN KEY (type_id) REFERENCES ledger_entry_types(type_id),
    INDEX (batch_id),
    INDEX (group_id),
    INDEX (status_id)
) ENGINE=InnoDB;

CREATE TABLE user_balances (
    user_id BINARY(16) NOT NULL,
    currency_code CHAR(3) NOT NULL,
    total_proposed DECIMAL(15, 2) DEFAULT 0.00,
    total_ratified DECIMAL(15, 2) DEFAULT 0.00,
    total_disputed DECIMAL(15, 2) DEFAULT 0.00,
    total_settled  DECIMAL(15, 2) DEFAULT 0.00,
    total_spent    DECIMAL(15, 2) DEFAULT 0.00,
    PRIMARY KEY (user_id, currency_code)
) ENGINE=InnoDB;

CREATE TABLE group_user_balances (
    group_id BINARY(16) NOT NULL,
    user_id BINARY(16) NOT NULL,
    currency_code CHAR(3) NOT NULL,
    net_balance DECIMAL(15, 2) DEFAULT 0.00,
    total_contributed DECIMAL(15, 2) DEFAULT 0.00,
    PRIMARY KEY (group_id, user_id, currency_code),
    INDEX (user_id)
) ENGINE=InnoDB;

INSERT INTO ledger_statuses (status_id, name) VALUES (1, 'proposed'), (2, 'ratified'), (3, 'disputed'), (4, 'settled');
INSERT INTO ledger_entry_types (type_id, name) VALUES (1, 'expense'), (2, 'settlement');

DELIMITER //
CREATE PROCEDURE sync_all_balances(
    IN p_uid BINARY(16),
    IN p_gid BINARY(16),
    IN p_curr CHAR(3),
    IN p_amt DECIMAL(15,2),
    IN p_status TINYINT,
    IN p_type TINYINT,
    IN p_mod INT
)
BEGIN
    INSERT INTO user_balances (user_id, currency_code) VALUES (p_uid, p_curr)
    ON DUPLICATE KEY UPDATE user_id = user_id;
    UPDATE user_balances SET
        total_proposed = total_proposed + IF(p_status = 1, p_amt * p_mod, 0),
        total_ratified = total_ratified + IF(p_status = 2, p_amt * p_mod, 0),
        total_disputed = total_disputed + IF(p_status = 3, p_amt * p_mod, 0),
        total_settled  = total_settled  + IF(p_status = 4, p_amt * p_mod, 0),
        total_spent    = total_spent    + IF(p_type = 1 AND p_amt > 0, p_amt * p_mod, 0)
    WHERE user_id = p_uid AND currency_code = p_curr;
    IF p_gid IS NOT NULL THEN
        INSERT INTO group_user_balances (group_id, user_id, currency_code, net_balance, total_contributed)
        VALUES (p_gid, p_uid, p_curr, p_amt * p_mod, IF(p_type = 1 AND p_amt > 0, p_amt * p_mod, 0))
        ON DUPLICATE KEY UPDATE
            net_balance = net_balance + (p_amt * p_mod),
            total_contributed = total_contributed + IF(p_type = 1 AND p_amt > 0, p_amt * p_mod, 0);
    END IF;
END //
CREATE TRIGGER after_ledger_insert AFTER INSERT ON ledger FOR EACH ROW
BEGIN
    CALL sync_all_balances(NEW.user_id, NEW.group_id, NEW.currency_code, NEW.amount, NEW.status_id, NEW.type_id, 1);
END //
CREATE TRIGGER after_ledger_update AFTER UPDATE ON ledger FOR EACH ROW
BEGIN
    CALL sync_all_balances(OLD.user_id, OLD.group_id, OLD.currency_code, OLD.amount, OLD.status_id, OLD.type_id, -1);
    CALL sync_all_balances(NEW.user_id, NEW.group_id, NEW.currency_code, NEW.amount, NEW.status_id, NEW.type_id, 1);
END //
CREATE TRIGGER after_ledger_delete AFTER DELETE ON ledger FOR EACH ROW
BEGIN
    CALL sync_all_balances(OLD.user_id, OLD.group_id, OLD.currency_code, OLD.amount, OLD.status_id, OLD.type_id, -1);
END //
DELIMITER ;