const schema = `
  CREATE TABLE IF NOT EXISTS sessions (
    id          INTEGER PRIMARY KEY AUTOINCREMENT,
    external_id TEXT    UNIQUE NOT NULL,
    created_at  INTEGER NOT NULL DEFAULT (unixepoch()),
    updated_at  INTEGER NOT NULL DEFAULT (unixepoch()),
    metadata    TEXT
  );

  CREATE TABLE IF NOT EXISTS episodes (
    id            INTEGER PRIMARY KEY AUTOINCREMENT,
    session_id    INTEGER NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
    user_message  TEXT NOT NULL,
    ai_response   TEXT NOT NULL,
    created_at    INTEGER NOT NULL DEFAULT (unixepoch()),
    token_count   INTEGER,
    metadata      TEXT
  );

  CREATE TABLE IF NOT EXISTS entities (
    id         INTEGER PRIMARY KEY AUTOINCREMENT,
    name       TEXT    NOT NULL,
    type       TEXT    NOT NULL,
    notes      TEXT,
    created_at INTEGER NOT NULL DEFAULT (unixepoch()),
    updated_at INTEGER NOT NULL DEFAULT (unixepoch()),
    metadata   TEXT,
    UNIQUE(name, type)
  );

  CREATE TABLE IF NOT EXISTS relationships (
    id         INTEGER PRIMARY KEY AUTOINCREMENT,
    from_id    INTEGER NOT NULL REFERENCES entities(id) ON DELETE CASCADE,
    to_id      INTEGER NOT NULL REFERENCES entities(id) ON DELETE CASCADE,
    label      TEXT    NOT NULL,
    created_at INTEGER NOT NULL DEFAULT (unixepoch()),
    metadata   TEXT,
    UNIQUE(from_id, to_id, label)
  );

  CREATE INDEX IF NOT EXISTS idx_relationships_from ON relationships(from_id);
  CREATE INDEX IF NOT EXISTS idx_relationships_to   ON relationships(to_id);

  CREATE TABLE IF NOT EXISTS entity_episodes (
    entity_id  INTEGER NOT NULL REFERENCES entities(id) ON DELETE CASCADE,
    episode_id INTEGER NOT NULL REFERENCES episodes(id) ON DELETE CASCADE,
    PRIMARY KEY (entity_id, episode_id)
  );

  CREATE INDEX IF NOT EXISTS idx_entity_episodes_entity  ON entity_episodes(entity_id);
  CREATE INDEX IF NOT EXISTS idx_entity_episodes_episode ON entity_episodes(episode_id);
  


  CREATE TABLE IF NOT EXISTS projects (
    id          INTEGER PRIMARY KEY AUTOINCREMENT,
    name        TEXT NOT NULL,
    description TEXT,
    colour      TEXT,
    icon        TEXT,
    created_at  INTEGER NOT NULL DEFAULT (unixepoch())
  );

  CREATE TABLE IF NOT EXISTS summaries (
    id            INTEGER PRIMARY KEY AUTOINCREMENT,
    session_id    INTEGER REFERENCES sessions(id) ON DELETE CASCADE,
    project_id    INTEGER REFERENCES projects(id) ON DELETE CASCADE,
    content       TEXT    NOT NULL,
    token_count   INTEGER,
    episode_range TEXT,
    created_at    INTEGER NOT NULL DEFAULT (unixepoch()),
    metadata      TEXT
  );

  CREATE INDEX IF NOT EXISTS idx_episodes_session 
    ON episodes(session_id);
  CREATE INDEX IF NOT EXISTS idx_episodes_created 
    ON episodes(created_at);
  CREATE INDEX IF NOT EXISTS idx_entities_type 
    ON entities(type);

  CREATE VIRTUAL TABLE IF NOT EXISTS episodes_fts 
    USING fts5(user_message, ai_response, content=episodes, content_rowid=id);

    CREATE TRIGGER IF NOT EXISTS episodes_fts_insert
    AFTER INSERT ON episodes BEGIN
      INSERT INTO episodes_fts(rowid, user_message, ai_response)
      VALUES (new.id, new.user_message, new.ai_response);
    END;

  CREATE TRIGGER IF NOT EXISTS episodes_fts_delete
    AFTER DELETE ON episodes BEGIN
      INSERT INTO episodes_fts(episodes_fts, rowid, user_message, ai_response)
      VALUES ('delete', old.id, old.user_message, old.ai_response);
    END;

  CREATE TRIGGER IF NOT EXISTS episodes_fts_update
    AFTER UPDATE ON episodes BEGIN
      INSERT INTO episodes_fts(episodes_fts, rowid, user_message, ai_response)
      VALUES ('delete', old.id, old.user_message, old.ai_response);
      INSERT INTO episodes_fts(rowid, user_message, ai_response)
      VALUES (new.id, new.user_message, new.ai_response);
    END;
  
  
`;

module.exports = schema;