Order of Mirror Entity and Mind Control Tech Effect Resolutions [duplicate]

Example:

Player 1 has a Mirror Entity in play (Secret: When your opponent plays a minion, summon a copy of it). He also has 3 minions on the board.

Player 2 starts his turn with no minions and plays a Mind Control Tech (Battlecry: If your opponent has 4 or more minions, take control of one at random).

What happens? Extra credit: what happens if Player 2 started with 3 minions before playing his Mind Control Tech?

Just trying to wrap my head around the mechanics. Thanks.

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Edit: this is different from the How is effect precedence determined link because the accepted answer on that question is not relevant to Secrets and does not go into detail on their usage.

In that answer, quote: "According to Lead Designer Eric Dodds, events such as Deathrattles that are triggered simultaneously will occur in the order in which the related cards were played.".

Secrets don't enter the stack when they were played, but rather as they are triggered which is a subtle but important point to this question (and something I learned through the accepted answer on here and some of the commentary from Waterseas).