package jobs

import (
	"context"
	"encoding/json"
	"fmt"
	"sync"
	"time"

	"git.nakama.town/fmartingr/hako/internal/model"
	"github.com/google/uuid"
)

// MemoryQueue implements an in-memory job queue
type MemoryQueue struct {
	jobs   chan *model.Job
	mu     sync.Mutex
	jobMap map[string]*model.Job
}

// NewMemoryQueue creates a new in-memory queue
func NewMemoryQueue() *MemoryQueue {
	return &MemoryQueue{
		jobs:   make(chan *model.Job, 100), // Buffer of 100 jobs
		jobMap: make(map[string]*model.Job),
	}
}

// Enqueue adds a new job to the queue
func (q *MemoryQueue) Enqueue(ctx context.Context, jobType model.JobType, payload any) error {
	// Marshal payload to JSON
	payloadBytes, err := json.Marshal(payload)
	if err != nil {
		return fmt.Errorf("failed to marshal payload: %w", err)
	}

	job := &model.Job{
		ID:        uuid.New().String(),
		Type:      jobType,
		Payload:   string(payloadBytes),
		Status:    "pending",
		CreatedAt: time.Now(),
	}

	q.mu.Lock()
	q.jobMap[job.ID] = job
	q.mu.Unlock()

	// Send to channel
	select {
	case q.jobs <- job:
		return nil
	case <-ctx.Done():
		return ctx.Err()
	}
}

// Dequeue retrieves the next job from the queue
func (q *MemoryQueue) Dequeue(ctx context.Context) (*model.Job, error) {
	select {
	case job := <-q.jobs:
		q.mu.Lock()
		job.Status = "processing"
		q.mu.Unlock()
		return job, nil
	case <-ctx.Done():
		return nil, ctx.Err()
	default:
		return nil, nil // No job available
	}
}

// Complete marks a job as completed
func (q *MemoryQueue) Complete(ctx context.Context, jobID string) error {
	q.mu.Lock()
	defer q.mu.Unlock()

	if job, ok := q.jobMap[jobID]; ok {
		job.Status = "completed"
		return nil
	}

	return fmt.Errorf("job not found: %s", jobID)
}

// Fail marks a job as failed
func (q *MemoryQueue) Fail(ctx context.Context, jobID string, errorMsg string) error {
	q.mu.Lock()
	defer q.mu.Unlock()

	if job, ok := q.jobMap[jobID]; ok {
		job.Status = "failed"
		// Store error message in payload for now
		return nil
	}

	return fmt.Errorf("job not found: %s", jobID)
}