#!/bin/bash

# Derives Lambda resource names from CONTEXT or AWS.

# Usage: source "$SERVICE_PATH/utils/lambda_function_name"

# Requires: SCOPE_ID set

# Exports: LAMBDA_FUNCTION_NAME, LAMBDA_LOG_GROUP_NAME

_application_slug=$(echo "$CONTEXT" | jq -r '.application.slug // ""')

_scope_slug=$(echo "$CONTEXT" | jq -r '.scope.slug // ""')

if [ -n "$_application_slug" ] && [ -n "$_scope_slug" ]; then

# Lifecycle contexts (create/update/delete) include full application info.

LAMBDA_FUNCTION_NAME="${SCOPE_ID}-${_application_slug}-${_scope_slug}"

LAMBDA_FUNCTION_NAME="${LAMBDA_FUNCTION_NAME:0:64}"

else

# Action contexts (log/metric/instance/diagnose) may omit application info.

# Look up the function by the scope-id tag set by Terraform.

_lambda_arn=$(aws resourcegroupstaggingapi get-resources \

--tag-filters "Key=nullplatform:scope-id,Values=${SCOPE_ID}" \

--resource-type-filters lambda:function \

--query "ResourceTagMappingList[0].ResourceARN" \

--output text 2>/dev/null || echo "")

if [ -n "$_lambda_arn" ] && [ "$_lambda_arn" != "None" ]; then

LAMBDA_FUNCTION_NAME="${_lambda_arn##*:function:}"

fi

fi

# Log group name follows the AWS Lambda convention, matching the Terraform

# resource in deployment/compute/lambda/modules/locals.tf

LAMBDA_LOG_GROUP_NAME="/aws/lambda/${LAMBDA_FUNCTION_NAME}"

export LAMBDA_FUNCTION_NAME

export LAMBDA_LOG_GROUP_NAME

unset _application_slug _scope_slug _lambda_arn