Add mid-range pass odds strategy

README.md

@@ -45,6 +45,7 @@ function myStrategy ({ rules, bets, hand, playerMind }) { ... }
 | `noBetting` | Makes no bets. Useful as a baseline or placeholder. |
 | `minPassLineOnly` | Pass line bet at `minBet` on each come-out. No odds. |
 | `minPassLineMaxOdds` | Pass line at `minBet` + maximum odds behind the line once a point is set. |
+| `minPassLineMidOdds` | Pass line at `minBet` + approximately half of maximum odds once a point is set. Odds multiple is `Math.ceil(maxOddsMultiple / 2)`. |
 | `minPassLineMinOdds` | Pass line at `minBet` + minimum payable odds once a point is set. Rounds up to nearest $5 for points 6/8, nearest even number for points 5/9, exact `minBet` for points 4/10. |
 | `placeSixEight` | Place the 6 and 8 at the nearest multiple of $6 ≥ `minBet`. No pass line. Bets come down on a win and are re-placed next turn. |
 | `minComeLineMaxOdds` | One come bet at `minBet` with max odds once it travels to a point. |

betting.js

@@ -81,6 +81,21 @@ function minPassLineMaxOdds (opts) {
   })
 }
 
+function minPassLineMidOdds (opts) {
+  const bets = minPassLineOnly(opts)
+  const { rules, hand } = opts
+
+  if (hand.isComeOut === false && !bets?.pass?.odds) {
+    const maxMultiple = rules.maxOddsMultiple[hand.point]
+    const oddsMultiple = Math.ceil(maxMultiple / 2)
+    const oddsAmount = oddsMultiple * bets.pass.line.amount
+    bets.pass.odds = { amount: oddsAmount }
+    bets.new += oddsAmount
+  }
+
+  return bets
+}
+
 function minPassLineMinOdds (opts) {
   const bets = minPassLineOnly(opts)
   const { rules, hand } = opts
@@ -318,6 +333,7 @@ module.exports = {
   minPassLineOnly,
   lineMaxOdds,
   minPassLineMaxOdds,
+  minPassLineMidOdds,
   minPassLineMinOdds,
   placeSixEight,
   placeSixEightUnlessPoint,

betting.test.js

@@ -1392,3 +1392,26 @@ tap.test('minPassLineMinOdds: no odds on come-out', (t) => {
   t.notOk(result.pass?.odds, 'no odds on come-out')
   t.end()
 })
+
+tap.test('minPassLineMidOdds: places roughly half of max odds on point set', (t) => {
+  const rules = { minBet: 5, maxOddsMultiple: { 4: 3, 5: 4, 6: 5, 8: 5, 9: 4, 10: 3 } }
+  const hand = { isComeOut: false, result: 'point set', point: 5 }
+  const bets = { pass: { line: { amount: 5 } } }
+
+  const result = lib.minPassLineMidOdds({ rules, bets, hand })
+  const expectedMultiple = Math.ceil(rules.maxOddsMultiple[5] / 2)
+
+  t.ok(result.pass.odds, 'odds placed')
+  t.equal(result.pass.odds.amount, expectedMultiple * rules.minBet, 'odds at ceil(maxMultiple/2) * minBet')
+  t.end()
+})
+
+tap.test('minPassLineMidOdds: no odds on come-out', (t) => {
+  const rules = { minBet: 5, maxOddsMultiple: { 4: 3, 5: 4, 6: 5, 8: 5, 9: 4, 10: 3 } }
+  const hand = { isComeOut: true }
+
+  const result = lib.minPassLineMidOdds({ rules, hand })
+
+  t.notOk(result.pass?.odds, 'no odds on come-out')
+  t.end()
+})