Adv 2.0 D&D Phase R R3-R5: Combat-link, zone loot, fishing, economy

R3 — Combat Event Integration:
- dnd_expedition_combat.go: Combat Interrupt rolls (§4.2) with
  threat-clock and Ranger-wilderness modifiers; Patrol Encounters
  scaled by threat level; recordZoneKill writer with monsterKillTags.
- Interrupt gate at head of handleHarvestCmd; patrol gate before
  resolveRoom in zoneCmdAdvance; kill writer wired into combat-win
  paths.

R4a — Zone Loot Tables:
- dnd_zone_loot.go: §5 loot drop tables for all 10 zones × 5 tiers
  with §8.1 sell-value bands. dropTierFromCR brackets + boss floor.
- Hooks on combat-win in resolveCombatRoom, resolveBossRoom,
  runHarvestInterrupt, tryPatrolEncounter.

R4b — Fishing Integration:
- dnd_zone_fish.go: fishingZones allow-list, fishingSkillBonus,
  rangerRareCatchUpgrade (§6.2), feywildFishDistortion narration.
- §6.1 fish entries added to resource registry for Forest, Sunken
  Temple, Underdark, Feywild zones.
- !fish wired through handleHarvestCmd; zoneItemFlavor matrix
  populated for all 10 zones × all loot items.

R5 — Economy Integration:
- dnd_economy.go: !sell (post-expedition gate, single CHA Persuasion
  DC 17 → +15% bump), !craft (§8.2 4 exemplar recipes), !lore
  (INT/Arcana DC 15 recipe discovery).
- dnd_known_recipe table for persistent recipe discovery.

Flavor reuse: HarvestInterrupt, PatrolEncounter, CombatVictory,
PlayerDeath, LootDrop*, FeywildTimeDistortion* — all existing pools.
No new flavor file.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/plugin/dnd_zone_fish_test.go

@@ -0,0 +1,196 @@
+package plugin
+
+import (
+	"math/rand/v2"
+	"testing"
+)
+
+// ── §6.1 Fishing zone gate ─────────────────────────────────────────────────
+
+func TestIsFishingZone_AllowList(t *testing.T) {
+	allowed := map[ZoneID]bool{
+		ZoneForestShadows:   true,
+		ZoneSunkenTemple:    true,
+		ZoneUnderdark:       true,
+		ZoneFeywildCrossing: true,
+	}
+	all := []ZoneID{
+		ZoneGoblinWarrens, ZoneCryptValdris, ZoneForestShadows,
+		ZoneSunkenTemple, ZoneManorBlackspire, ZoneUnderforge,
+		ZoneUnderdark, ZoneFeywildCrossing, ZoneDragonsLair, ZoneAbyssPortal,
+	}
+	for _, z := range all {
+		if got, want := isFishingZone(z), allowed[z]; got != want {
+			t.Errorf("isFishingZone(%s) = %v, want %v", z, got, want)
+		}
+	}
+}
+
+// ── §6.2 fishing skill bonus folds in legacy rank ──────────────────────────
+
+func TestFishingSkillBonus_Bands(t *testing.T) {
+	cases := []struct {
+		skill int
+		want  int
+	}{
+		{0, 0}, {1, 0}, {4, 0}, {5, 1}, {9, 1}, {10, 2}, {15, 2}, {99, 2},
+	}
+	for _, c := range cases {
+		if got := fishingSkillBonus(c.skill); got != c.want {
+			t.Errorf("fishingSkillBonus(%d) = %d, want %d", c.skill, got, c.want)
+		}
+	}
+}
+
+// ── §6.2 Ranger +20% rare-catch upgrade ────────────────────────────────────
+
+func TestRangerRareCatchUpgrade_OnlyAppliesToFish(t *testing.T) {
+	// Non-fish action: never upgrade, even for rangers.
+	rng := rand.New(rand.NewPCG(1, 1))
+	for i := 0; i < 100; i++ {
+		got := rangerRareCatchUpgrade(ClassRanger, HarvestForage, OutcomeStandard, rng)
+		if got != OutcomeStandard {
+			t.Fatalf("non-fish action upgraded: %s", got)
+		}
+	}
+	// Non-ranger fish: never upgrade.
+	rng = rand.New(rand.NewPCG(2, 2))
+	for i := 0; i < 100; i++ {
+		got := rangerRareCatchUpgrade(ClassFighter, HarvestFish, OutcomeStandard, rng)
+		if got != OutcomeStandard {
+			t.Fatalf("non-ranger upgraded: %s", got)
+		}
+	}
+	// Ranger fish + Rich/Nothing: passes through unchanged.
+	rng = rand.New(rand.NewPCG(3, 3))
+	for i := 0; i < 100; i++ {
+		if got := rangerRareCatchUpgrade(ClassRanger, HarvestFish, OutcomeRich, rng); got != OutcomeRich {
+			t.Fatalf("Rich changed: %s", got)
+		}
+		if got := rangerRareCatchUpgrade(ClassRanger, HarvestFish, OutcomeNothing, rng); got != OutcomeNothing {
+			t.Fatalf("Nothing changed: %s", got)
+		}
+	}
+}
+
+func TestRangerRareCatchUpgrade_RoughRate(t *testing.T) {
+	rng := rand.New(rand.NewPCG(7, 7))
+	const trials = 4000
+	upgrades := 0
+	for i := 0; i < trials; i++ {
+		out := rangerRareCatchUpgrade(ClassRanger, HarvestFish, OutcomeStandard, rng)
+		if out == OutcomeRich {
+			upgrades++
+		}
+	}
+	rate := float64(upgrades) / float64(trials)
+	if rate < 0.15 || rate > 0.25 {
+		t.Errorf("upgrade rate %.3f outside expected ~0.20 ±0.05", rate)
+	}
+}
+
+// ── §6.1 Feywild Time Distortion narration hook ─────────────────────────────
+
+func TestFeywildFishDistortion_OnlyFiresInFeywildOnFish(t *testing.T) {
+	rng := rand.New(rand.NewPCG(11, 11))
+	for i := 0; i < 200; i++ {
+		if got := feywildFishDistortion(ZoneForestShadows, HarvestFish, rng); got != "" {
+			t.Fatalf("non-feywild fired: %q", got)
+		}
+		if got := feywildFishDistortion(ZoneFeywildCrossing, HarvestForage, rng); got != "" {
+			t.Fatalf("non-fish action fired: %q", got)
+		}
+	}
+}
+
+// ── §3 fish entries present in registry per §6.1 zones ─────────────────────
+
+func TestZoneFishRegistry_Coverage(t *testing.T) {
+	want := map[ZoneID][]string{
+		ZoneForestShadows:   {"shadow_trout", "gloomfin", "phantom_carp"},
+		ZoneSunkenTemple:    {"black_pearl", "blind_cave_fish", "merrow_eel", "dareth_lanternfish", "aboleth_spawn"},
+		ZoneUnderdark:       {"blind_albino_bass", "glowing_cave_eel", "underdark_shark", "eyeless_king"},
+		ZoneFeywildCrossing: {"moonlit_minnow", "dreaming_pike", "timeworn_koi"},
+	}
+	for zid, ids := range want {
+		seen := map[string]bool{}
+		for _, r := range ZoneResourcesByAction(zid, HarvestFish) {
+			seen[r.ID] = true
+		}
+		for _, id := range ids {
+			if !seen[id] {
+				t.Errorf("zone %s missing fish entry %s", zid, id)
+			}
+		}
+	}
+	// And: zones not on the §6.1 list should have no fish entries.
+	noFish := []ZoneID{
+		ZoneGoblinWarrens, ZoneCryptValdris, ZoneManorBlackspire,
+		ZoneUnderforge, ZoneDragonsLair, ZoneAbyssPortal,
+	}
+	for _, z := range noFish {
+		if got := ZoneResourcesByAction(z, HarvestFish); len(got) != 0 {
+			t.Errorf("zone %s has %d fish entries, want 0", z, len(got))
+		}
+	}
+}
+
+// ── §5 zone-contextual item flavor matrix ──────────────────────────────────
+
+func TestZoneItemDescription_LootMatrixCoverage(t *testing.T) {
+	// Every zone's loot table entry name should resolve to either a
+	// flavor line or the Potion of Healing exemplar — but the specific
+	// invariant we want is: every zone has *some* per-item flavor populated
+	// beyond just Potion of Healing.
+	zones := []ZoneID{
+		ZoneGoblinWarrens, ZoneCryptValdris, ZoneForestShadows,
+		ZoneSunkenTemple, ZoneManorBlackspire, ZoneUnderforge,
+		ZoneUnderdark, ZoneFeywildCrossing, ZoneDragonsLair, ZoneAbyssPortal,
+	}
+	for _, z := range zones {
+		zm, ok := zoneItemFlavor[z]
+		if !ok || len(zm) == 0 {
+			t.Errorf("zone %s: no item flavor matrix populated", z)
+			continue
+		}
+		// Every flavor entry should resolve via the public path.
+		for name, want := range zm {
+			if got := zoneItemDescription(z, name); got != want {
+				t.Errorf("zone %s item %q: zoneItemDescription mismatch", z, name)
+			}
+		}
+	}
+}
+
+func TestZoneItemDescription_MissingItemReturnsEmpty(t *testing.T) {
+	if got := zoneItemDescription(ZoneGoblinWarrens, "Nonexistent Item"); got != "" {
+		t.Errorf("got %q, want empty for unknown item", got)
+	}
+}
+
+// ── Fish entries respect §8.1 sell-value bands ──────────────────────────────
+
+func TestZoneFish_SellValueBands(t *testing.T) {
+	bands := map[DnDRarity][2]int{
+		RarityCommon:    {3, 20},
+		RarityUncommon:  {25, 70},
+		RarityRare:      {100, 350},
+		RarityVeryRare:  {500, 1500},
+		RarityLegendary: {3000, 10000},
+	}
+	zones := []ZoneID{
+		ZoneForestShadows, ZoneSunkenTemple, ZoneUnderdark, ZoneFeywildCrossing,
+	}
+	for _, z := range zones {
+		for _, r := range ZoneResourcesByAction(z, HarvestFish) {
+			band, ok := bands[r.Rarity]
+			if !ok {
+				t.Errorf("fish %s has unhandled rarity %s", r.ID, r.Rarity)
+				continue
+			}
+			if r.SellValue < band[0] || r.SellValue > band[1] {
+				t.Errorf("fish %s sell %d outside band %v for %s", r.ID, r.SellValue, band, r.Rarity)
+			}
+		}
+	}
+}