-- Version 1 is the initial structure.
CREATE TABLE [Version] (
    [id] INTEGER PRIMARY KEY,
    [version] INTEGER NOT NULL UNIQUE,
    [datetime] DATETIME
);

CREATE TABLE [User] (
    [id] INTEGER PRIMARY KEY,
    [email] TEXT NOT NULL,
    [password] TEXT NOT NULL, -- Hashed and salted.
    [name] TEXT NOT NULL
);

CREATE TABLE [Recipe] (
    [id] INTEGER PRIMARY KEY,
    [user_id] INTEGER NOT NULL,
    [title] TEXT NOT NULL,
    [estimate_time] INTEGER,
    [description] TEXT,

    FOREIGN KEY([user_id]) REFERENCES [User]([id])
);

CREATE TABLE [Quantity] (
    [id] INTEGER PRIMARY KEY,
    [value] REAL,
    [unit] TEXT
);

CREATE TABLE [Ingredient] (
    [id] INTEGER PRIMARY KEY,
    [name] TEXT NOT NULL,
    [quantity_id] INTEGER,
    [input_step_id] INTEGER NOT NULL,

    FOREIGN KEY([quantity_id]) REFERENCES Quantity([id]),
    FOREIGN KEY([input_step_id]) REFERENCES Step([id])
);

CREATE TABLE [Group] (
    [id] INTEGER PRIMARY KEY,
    [order] INTEGER NOT NULL DEFAULT 0,
    [recipe_id] INTEGER,
    name TEXT,

    FOREIGN KEY([recipe_id]) REFERENCES [Recipe]([id])
);

CREATE INDEX [Group_order_index] ON [Group] ([order]);

CREATE TABLE [Step] (
    [id] INTEGER PRIMARY KEY,
    [order] INTEGER NOT NULL DEFAULT 0,
    [action] TEXT NOT NULL,
    [group_id] INTEGER NOT NULL,

    FOREIGN KEY(group_id) REFERENCES [Group](id)
);

CREATE INDEX [Step_order_index] ON [Group] ([order]);

CREATE TABLE [IntermediateSubstance] (
    [id] INTEGER PRIMARY KEY,
    [name] TEXT NOT NULL,
    [quantity_id] INTEGER,
    [output_step_id] INTEGER NOT NULL,
    [input_step_id] INTEGER NOT NULL,

    FOREIGN KEY([quantity_id]) REFERENCES [Quantity]([id]),
    FOREIGN KEY([output_step_id]) REFERENCES [Step]([id]),
    FOREIGN KEY([input_step_id]) REFERENCES [Step]([id])
);