package mq

import (
	"context"

	"github.com/oarkflow/mq/storage"
	"github.com/oarkflow/mq/storage/memory"
)

type Queue struct {
	consumers storage.IMap[string, *consumer]
	tasks     chan *QueuedTask // channel to hold tasks
	name      string
}

func newQueue(name string, queueSize int) *Queue {
	return &Queue{
		name:      name,
		consumers: memory.New[string, *consumer](),
		tasks:     make(chan *QueuedTask, queueSize), // buffer size for tasks
	}
}

func (b *Broker) NewQueue(name string) *Queue {
	q := &Queue{
		name:      name,
		tasks:     make(chan *QueuedTask, b.opts.queueSize),
		consumers: memory.New[string, *consumer](),
	}
	b.queues.Set(name, q)

	// Create DLQ for the queue
	dlq := &Queue{
		name:      name + "_dlq",
		tasks:     make(chan *QueuedTask, b.opts.queueSize),
		consumers: memory.New[string, *consumer](),
	}
	b.deadLetter.Set(name, dlq)

	go b.dispatchWorker(q)
	go b.dispatchWorker(dlq)
	return q
}

type QueueTask struct {
	ctx      context.Context
	payload  *Task
	priority int
}

type PriorityQueue []*QueueTask

func (pq PriorityQueue) Len() int { return len(pq) }

func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority > pq[j].priority
}

func (pq PriorityQueue) Swap(i, j int) { pq[i], pq[j] = pq[j], pq[i] }

func (pq *PriorityQueue) Push(x interface{}) {
	item := x.(*QueueTask)
	*pq = append(*pq, item)
}

func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	*pq = old[0 : n-1]
	return item
}