CREATE TABLE IF NOT EXISTS actor (
	objectId TEXT,		-- UUIDv4 of the corresponding object
	preferredUsername TEXT,

	FOREIGN KEY (objectId) REFERENCES object(id),
	PRIMARY KEY (objectId)
);

CREATE TABLE IF NOT EXISTS object (
	id TEXT,		-- Dereferenceable link to the object
	type TEXT,		-- Object type, see <https://www.w3.org/TR/activitystreams-vocabulary/#object-types>

	name TEXT,		-- Title of the object
	attributedTo TEXT,	-- object ID of the actor to whom the object is attributed
	summary TEXT,		-- Natural language summary of the object
	content TEXT,		-- Text content or representation
	url TEXT,		-- A URL that represents the object
	mediaType TEXT,		-- MIME type of `content`
	icon TEXT,		-- URL of a 1:1 image that represents the object

	-- These four columns are unix timestamps. AP expects ISO timestamps
	startTime INTEGER,	-- When the object is said to have "begun," in some context
	endTime INTEGER,	-- When the object is said to "end," in some context
	published INTEGER,	-- When the object was first created
	updated INTEGER,	-- When the object was last updated

	FOREIGN KEY (attributedTo) REFERENCES object(id),
	PRIMARY KEY(id)
);

CREATE TABLE IF NOT EXISTS activity (
	objectId TEXT,

	-- All of these are object IDs, all of them are optional
	actor TEXT,		-- Actor "behind" the activity
	object TEXT,		-- Object encapsulated by the activity, if applicable
	origin TEXT,		-- Object the activity is "from"
	target TEXT,		-- Object the activity is "going to", or the encapsulated object is
	result TEXT,		-- Object describing the outcome
	instrument TEXT,	-- Object with which the activity was performed
	
	FOREIGN KEY (objectId) REFERENCES object(id),
	PRIMARY KEY (objectId)
);

CREATE TABLE IF NOT EXISTS object_contentMap (
	objectId INTEGER,	-- The object attaching `attachedId`
	key TEXT,		-- Langauge code
	content TEXT,		-- The content being mapped to by the key

	FOREIGN KEY(objectId) REFERENCES object(id),
	PRIMARY KEY(objectId, key)
);

CREATE TABLE IF NOT EXISTS object_attachment (
	objectId INTEGER,	-- The object attaching `attachedId`
	attachedId INTEGER,	-- The object attached by `objectId`

	FOREIGN KEY(objectId) REFERENCES object(id),
	FOREIGN KEY(attachedId) REFERENCES object(id),
	PRIMARY KEY(objectId, attachedId)
);

CREATE TABLE IF NOT EXISTS object_audience (
	objectId INTEGER,	-- Object identifying an audience
	audienceId INTEGER,	-- Audience being identified

	FOREIGN KEY(objectId) REFERENCES object(id),
	FOREIGN KEY(audienceId) REFERENCES object(id),
	PRIMARY KEY(objectId, audienceId)
);

CREATE TABLE IF NOT EXISTS object_replies (
	objectId INTEGER,	-- "original post," or whatever is being replied to
	responseId INTEGER,	-- The response to the original object

	FOREIGN KEY(objectId) REFERENCES object(id),
	FOREIGN KEY(responseId) REFERENCES object(id),
	PRIMARY KEY(objectId, responseId)
);

CREATE TABLE IF NOT EXISTS object_tags (
	taggerId INTEGER,
	taggedId INTEGER,

	FOREIGN KEY(taggerId) REFERENCES object(id),
	FOREIGN KEY(taggedId) REFERENCES object(id),
	PRIMARY KEY(taggerId, taggedId)
);