package main

import (
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
	"time"

	"github.com/kami/maven/internal/config"
	"github.com/kami/maven/internal/llm"
)

// No `workstation` block is the shipping deploy. The seam must then be the
// resident client itself, with nothing probing anything.
func TestModelSeamUnconfiguredIsResidentOnly(t *testing.T) {
	resident := llm.New("http://127.0.0.1:1", time.Second)
	hot, pair := modelSeam(&config.Config{}, resident)
	if pair != nil {
		t.Error("built a pair with no workstation configured")
	}
	if hot == nil {
		t.Fatal("no seam at all, so the cascade would route with the classifier")
	}
}

// A workstation with no resident model behind it has no floor, and a Pair with
// no floor is a configuration mistake rather than a degraded mode.
func TestModelSeamWithoutResidentIsNil(t *testing.T) {
	cfg := &config.Config{Workstation: &config.WorkstationConfig{URL: "http://127.0.0.1:1"}}
	cfg.Workstation.Health = strings.TrimRight(cfg.Workstation.URL, "/") + "/health"
	hot, pair := modelSeam(cfg, nil)
	if hot != nil || pair != nil {
		t.Errorf("built a seam with no floor: hot=%v pair=%v", hot, pair)
	}
}

// The configured case: the seam is the pair, and the pair notices a workstation
// that answers /health.
func TestModelSeamPrefersAnAnsweringWorkstation(t *testing.T) {
	up := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))
	defer up.Close()

	cfg := &config.Config{Workstation: &config.WorkstationConfig{
		URL:   up.URL,
		Probe: config.Duration(10 * time.Millisecond),
	}}
	cfg.Workstation.Health = strings.TrimRight(cfg.Workstation.URL, "/") + "/health"

	hot, pair := modelSeam(cfg, llm.New("http://127.0.0.1:1", time.Second))
	if pair == nil || hot == nil {
		t.Fatal("no pair built for a configured workstation")
	}
	defer pair.Stop()

	deadline := time.Now().Add(2 * time.Second)
	for !pair.Available() && time.Now().Before(deadline) {
		time.Sleep(5 * time.Millisecond)
	}
	if !pair.Available() {
		t.Fatal("the pair never saw a workstation that answers /health")
	}
}

// A card held by a CPT run answers 503, and that must read as unavailable
// rather than as an error a turn has to handle.
func TestModelSeamHeldCardIsUnavailable(t *testing.T) {
	busy := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		http.Error(w, "model not loaded", http.StatusServiceUnavailable)
	}))
	defer busy.Close()

	cfg := &config.Config{Workstation: &config.WorkstationConfig{
		URL:   busy.URL,
		Probe: config.Duration(10 * time.Millisecond),
	}}
	cfg.Workstation.Health = strings.TrimRight(cfg.Workstation.URL, "/") + "/health"

	_, pair := modelSeam(cfg, llm.New("http://127.0.0.1:1", time.Second))
	if pair == nil {
		t.Fatal("no pair built for a configured workstation")
	}
	defer pair.Stop()

	time.Sleep(50 * time.Millisecond)
	if pair.Available() {
		t.Error("a 503 from the supervisor read as available")
	}
}