# alias: FinesseSimple
# button-text: Finesse - Simple
# gib-works: true
# bba-works: true
# auction-filter: Auction.....\n1[NSH]
# curate: kind=soundness
# convention-card-ns: Basic-Bridge
# convention-card-ew: Basic-Bridge

/*@chat
--- Simple Finesse (3NT, 4!H, or 4!S by South)
South opens with a 5+-card major and the partnership reaches a major game
or 3NT. South declares.

Teaching feature: South holds an AQ in a SIDE suit without the K. The K is in
East or West, roughly half the time each way.

• When South opens 1!S, the finesse suit is ♥ (AQ-no-K).
• When South opens 1!H, the finesse suit is ♠ (AQ-no-K).
• 5-3-3-2 hands sometimes open 1NT and play 3NT — finesse still applies.

To take the finesse: lead small from dummy toward South's hand and play the Q
if East follows small. The Q wins about half the time.

Things to think about:
• Count winners and losers first.
• When in the play should you take the finesse?
• If the finesse loses, where else can you make tricks?
• Did the auction or the opening lead hint where the K sits?

Reference: https://www.bridgebum.com/finesse.php
@chat*/

dealer south

# ----- Path 1: South opens 1S (5+ spades, ≤4 hearts), finesse is in hearts -----
p1Shape = spades(south) > 4 and hearts(south) < 5
p1AQH   = hascard(south, AH) and hascard(south, QH) and not hascard(south, KH)
p1N     = spades(north) > 2 and not hascard(north, KH)
path1   = p1Shape and p1AQH and p1N

# ----- Path 2: South opens 1H (5+ hearts, ≤4 spades), finesse is in spades -----
p2Shape = hearts(south) > 4 and spades(south) < 5
p2AQS   = hascard(south, AS) and hascard(south, QS) and not hascard(south, KS)
p2N     = hearts(north) > 2 and not hascard(north, KS)
path2   = p2Shape and p2AQS and p2N

# ----- Common requirements -----
sHcp       = hcp(south) > 13 and hcp(south) < 18
sNoMinor5  = diamonds(south) < 5 and clubs(south) < 5
nHcp       = hcp(north) > 7 and hcp(north) < 12
nNoMinor5  = diamonds(north) < 5 and clubs(north) < 5

# ----- Combine -----
(path1 or path2) and sHcp and sNoMinor5 and nHcp and nNoMinor5

action
average "Path 1: 1S, finesse H" 100 * path1,
average "Path 2: 1H, finesse S" 100 * path2,
average "Finesse-K with East  " 100 * ((path1 and hascard(east, KH)) or (path2 and hascard(east, KS))),
average "Finesse-K with West  " 100 * ((path1 and hascard(west, KH)) or (path2 and hascard(west, KS))),
average "South HCP avg        "       hcp(south),
average "North HCP avg        "       hcp(north),