// Package vllm provides an Adapter that calls a vLLM server via its
// OpenAI-compatible /v1/chat/completions endpoint.
package vllm

import (
	"context"
	"fmt"

	"go.uber.org/zap"

	"iop/apps/node/internal/runtime"
	"iop/packages/config"
)

const Name = "vllm"

type Vllm struct {
	endpoint string
	logger   *zap.Logger
}

func New(cfg config.VllmConf, logger *zap.Logger) *Vllm {
	return &Vllm{
		endpoint: cfg.Endpoint,
		logger:   logger,
	}
}

func (v *Vllm) Name() string { return Name }

func (v *Vllm) Capabilities(_ context.Context) (runtime.Capabilities, error) {
	// TODO: query /v1/models from vLLM endpoint.
	return runtime.Capabilities{
		AdapterName:    Name,
		Models:         []string{},
		MaxConcurrency: 8,
	}, nil
}

func (v *Vllm) Execute(ctx context.Context, spec runtime.ExecutionSpec, sink runtime.EventSink) error {
	// TODO: implement streaming POST to v.endpoint/v1/chat/completions
	// with "stream": true and SSE response parsing.
	v.logger.Info("vllm adapter called",
		zap.String("run_id", spec.RunID),
		zap.String("model", spec.Model),
		zap.String("endpoint", v.endpoint),
	)
	return fmt.Errorf("vllm adapter: not yet implemented")
}