From collecting all the evidence from various Twitter threads. The general idea I get is this:
Hamas found out about the Israeli Gas/Economic corridor. They would soon be considered liquidated. Gaza had to go if this plan was to go forward.
So they planned for a year for an attack.
Israel likely knew of this. Even Egypt warned them of an attack.
But instead they ignored the intelligence and warnings. And Israel licensed a popular rave for a one time music festival, that would be situated close to the attack.
Israel now has the dead civilians, some international. For support for a clearing of Gaza. Hamas apparently took 250+ hostages, and yet Israel keeps bombing.