Add support for if-then-else condition.

packages/taco/src/conditions/if-then-else-condition.ts

@@ -0,0 +1,22 @@
+import { Condition } from './condition';
+import {
+  IfThenElseConditionProps,
+  ifThenElseConditionSchema,
+  IfThenElseConditionType,
+} from './schemas/if-then-else';
+import { OmitConditionType } from './shared';
+
+export {
+  IfThenElseConditionProps,
+  ifThenElseConditionSchema,
+  IfThenElseConditionType,
+} from './schemas/if-then-else';
+
+export class IfThenElseCondition extends Condition {
+  constructor(value: OmitConditionType<IfThenElseConditionProps>) {
+    super(ifThenElseConditionSchema, {
+      conditionType: IfThenElseConditionType,
+      ...value,
+    });
+  }
+}

packages/taco/src/conditions/index.ts

@@ -6,5 +6,6 @@ export * as condition from './condition';
 export * as conditionExpr from './condition-expr';
 export { ConditionFactory } from './condition-factory';
 export * as context from './context';
+export * as ifThenElse from './if-then-else-condition';
 export * as sequential from './sequential';
 export { base, predefined };

packages/taco/src/conditions/multi-condition.ts

@@ -1,13 +1,15 @@
 import { CompoundConditionType } from './compound-condition';
 import { ConditionProps } from './condition';
+import { IfThenElseConditionType } from './if-then-else-condition';
 import { ConditionVariableProps, SequentialConditionType } from './sequential';
 
 export const maxNestedDepth =
   (maxDepth: number) =>
-  (condition: ConditionProps, currentDepth = 1) => {
+  (condition: ConditionProps, currentDepth = 1): boolean => {
     if (
       condition.conditionType === CompoundConditionType ||
-      condition.conditionType === SequentialConditionType
+      condition.conditionType === SequentialConditionType ||
+      condition.conditionType === IfThenElseConditionType
     ) {
       if (currentDepth > maxDepth) {
         // no more multi-condition types allowed at this level
@@ -18,11 +20,22 @@ export const maxNestedDepth =
         return condition.operands.every((child: ConditionProps) =>
           maxNestedDepth(maxDepth)(child, currentDepth + 1),
         );
-      } else {
+      } else if (condition.conditionType === SequentialConditionType) {
         return condition.conditionVariables.every(
           (child: ConditionVariableProps) =>
             maxNestedDepth(maxDepth)(child.condition, currentDepth + 1),
         );
+      } else {
+        // if-then-else condition
+        const ifThenElseConditions = [];
+        ifThenElseConditions.push(condition.ifCondition);
+        ifThenElseConditions.push(condition.thenCondition);
+        if (typeof condition.elseCondition !== 'boolean') {
+          ifThenElseConditions.push(condition.elseCondition);
+        }
+        return ifThenElseConditions.every((child: ConditionProps) =>
+          maxNestedDepth(maxDepth)(child, currentDepth + 1),
+        );
       }
     }
 

packages/taco/src/conditions/schemas/if-then-else.ts

@@ -0,0 +1,30 @@
+import { z } from 'zod';
+
+import { maxNestedDepth } from '../multi-condition';
+
+import { baseConditionSchema } from './common';
+import { anyConditionSchema } from './utils';
+
+export const IfThenElseConditionType = 'if-then-else';
+
+export const ifThenElseConditionSchema: z.ZodSchema = z.lazy(() =>
+  baseConditionSchema
+    .extend({
+      conditionType: z
+        .literal(IfThenElseConditionType)
+        .default(IfThenElseConditionType),
+      ifCondition: anyConditionSchema,
+      thenCondition: anyConditionSchema,
+      elseCondition: z.union([anyConditionSchema, z.boolean()]),
+    })
+    .refine(
+      (condition) => maxNestedDepth(2)(condition),
+      {
+        message: 'Exceeded max nested depth of 2 for multi-condition type',
+      }, // Max nested depth of 2
+    ),
+);
+
+export type IfThenElseConditionProps = z.infer<
+  typeof ifThenElseConditionSchema
+>;

packages/taco/src/conditions/schemas/utils.ts

@@ -3,6 +3,7 @@ import { z } from 'zod';
 import { compoundConditionSchema } from '../compound-condition';
 
 import { contractConditionSchema } from './contract';
+import { ifThenElseConditionSchema } from './if-then-else';
 import { jsonApiConditionSchema } from './json-api';
 import { rpcConditionSchema } from './rpc';
 import { sequentialConditionSchema } from './sequential';
@@ -16,5 +17,6 @@ export const anyConditionSchema: z.ZodSchema = z.lazy(() =>
     compoundConditionSchema,
     jsonApiConditionSchema,
     sequentialConditionSchema,
+    ifThenElseConditionSchema,
   ]),
 );