package elb

import (
	"dagger.io/dagger/op"
	"dagger.io/aws"
)

// Returns a non-taken rule priority (randomized)
#RandomRulePriority: {
	// AWS Config
	config: aws.#Config

	// ListenerArn
	listenerArn: string @dagger(input)

	// Optional vhost for reusing priorities
	vhost?: string @dagger(input)

	// exported priority
	priority: out @dagger(output)

	out: {
		string

		#up: [
			op.#Load & {
				from: aws.#CLI & {
					"config": config
				}
			},

			op.#Exec & {
				args: [
					"/bin/bash",
					"--noprofile",
					"--norc",
					"-eo",
					"pipefail",
					#"""
                    if [ -s "$VHOST" ]; then
                    	# We passed a vhost as input, try to recycle priority from previously allocated vhost
                    	priority=$(aws elbv2 describe-rules \
                    		--listener-arn "$LISTENER_ARN" | \
                    		jq -r --arg vhost "$VHOST" '.Rules[] | select(.Conditions[].HostHeaderConfig.Values[] == $VHOST) | .Priority')
                    
                    	if [ -n "${priority}" ]; then
                    		echo -n "${priority}" > /priority
                    		exit 0
                    	fi
                    fi

                    # Grab a priority random from 1-50k and check if available, retry 10 times if none available
                    priority=0
                    for i in {1..10}
                    do
                    	p=$(shuf -i 1-50000 -n 1)
                    	# Find the next priority available that we can allocate
                    	aws elbv2 describe-rules \
                    		--listener-arn "$LISTENER_ARN" \
                    		| jq -e "select(.Rules[].Priority == \"${p}\") | true" && continue
                    	priority="${p}"
                    	break
                    done
                    if [ "${priority}" -lt 1 ]; then
                    	echo "Error: cannot determine a Rule priority"
                    	exit 1
                    fi
                    echo -n "${priority}" > /priority
                    """#,
				]
				env: {
					LISTENER_ARN: listenerArn
					VHOST:        vhost
				}
			},

			op.#Export & {
				source: "/db_created"
				format: "string"
			},
		]
	}
}