role-playing-game

role-playing-game/src/role_playing_game.gleam

@@ -0,0 +1,96 @@
+import gleam/option.{type Option, None, Some}
+
+pub type Player {
+  Player(name: Option(String), level: Int, health: Int, mana: Option(Int))
+}
+
+pub fn introduce(player: Player) -> String {
+  case player.name {
+    option.None -> "Mighty Magician"
+    option.Some(name) -> name
+  }
+}
+
+pub fn revive(player: Player) -> Option(Player) {
+  case player.health <= 0 {
+    False -> None
+    True -> {
+      case player.level >= 10 {
+        False ->
+          Some(Player(
+            name: player.name,
+            level: player.level,
+            health: 100,
+            mana: None,
+          ))
+        True ->
+          Some(Player(
+            name: player.name,
+            level: player.level,
+            health: 100,
+            mana: Some(100),
+          ))
+      }
+    }
+  }
+}
+
+// The `cast_spell` function takes as arguments an `Int` indicating how much mana the spell costs as well as a `Player`.
+// It returns the updated player, as well as the amount of damage that the cast spell performs.
+// A successful spell cast does damage equal to two times the mana cost of the spell.
+// However, if the player has insufficient mana, nothing happens, the player is unchanged and no damage is done.
+// If the player does not even have a mana pool, attempting to cast the spell must decrease their health by the mana cost of the spell and does no damage.
+// Be aware that the players health cannot be below zero (0).
+
+pub fn cast_spell(player: Player, cost: Int) -> #(Player, Int) {
+  let damage = cost * 2
+
+  case player.mana {
+    None -> {
+      let health = player.health - cost
+      case health {
+        h if h > 0 -> #(
+          Player(
+            name: player.name,
+            level: player.level,
+            health:,
+            mana: player.mana,
+          ),
+          0,
+        )
+        _ -> #(
+          Player(
+            name: player.name,
+            level: player.level,
+            health: 0,
+            mana: player.mana,
+          ),
+          0,
+        )
+      }
+    }
+
+    Some(mana) -> {
+      let mana_left = mana - cost
+      case mana_left {
+        ml if ml >= 0 -> #(
+          Player(
+            name: player.name,
+            level: player.level,
+            health: player.health,
+            mana: Some(ml),
+          ),
+          damage,
+        )
+        _ -> #(player, 0)
+      }
+      // let health = player.health - damage
+      // case health {
+      //   h if h > 0 ->
+      //     Player(name: player.name, level: player.level, health:, mana: todo)
+      //   _ ->
+      //     Player(name: player.name, level: player.level, health: 0, mana: mana)
+      // }
+    }
+  }
+}