package modelselection

import (
	"testing"

	"voicesnap/internal/config"
	"voicesnap/internal/model"
)

type fakeDetector struct {
	locale string
}

func (f fakeDetector) Detect() string {
	return f.locale
}

func TestResolveAutoUsesEnglishDefaultModel(t *testing.T) {
	cfg := config.Default()
	cfg.LanguageMode = config.LanguageModeAuto
	cfg.ModelSelectionMode = config.ModelSelectionModeAuto

	current := Resolve(cfg, fakeDetector{locale: "en-US"})
	if current.ModelID != model.MoonshineModelID {
		t.Fatalf("model id = %q, want %q", current.ModelID, model.MoonshineModelID)
	}
	if current.Profile.BackendKind != model.BackendMoonshine {
		t.Fatalf("backend = %q, want %q", current.Profile.BackendKind, model.BackendMoonshine)
	}
}

func TestResolveAutoUsesChineseDefaultModel(t *testing.T) {
	cfg := config.Default()
	cfg.LanguageMode = config.LanguageModeAuto
	cfg.ModelSelectionMode = config.ModelSelectionModeAuto

	current := Resolve(cfg, fakeDetector{locale: "zh-CN"})
	if current.ModelID != model.DefaultModelID {
		t.Fatalf("model id = %q, want %q", current.ModelID, model.DefaultModelID)
	}
}

func TestResolveOldConfigMissingSelectionModeUsesAuto(t *testing.T) {
	cfg := config.Default()
	cfg.LanguageMode = config.LanguageModeAuto
	cfg.ModelSelectionMode = ""
	cfg.SelectedModelID = model.DefaultModelID

	current := Resolve(cfg, fakeDetector{locale: "en-US"})
	if current.SelectionMode != config.ModelSelectionModeAuto {
		t.Fatalf("selection mode = %q, want auto", current.SelectionMode)
	}
	if current.ModelID != model.MoonshineModelID {
		t.Fatalf("old selected model locked current model to %q, want %q", current.ModelID, model.MoonshineModelID)
	}
}

func TestResolveManualUsesSelectedModel(t *testing.T) {
	cfg := config.Default()
	cfg.LanguageMode = config.LanguageModeAuto
	cfg.ModelSelectionMode = config.ModelSelectionModeManual
	cfg.SelectedModelID = model.DefaultModelID

	current := Resolve(cfg, fakeDetector{locale: "en-US"})
	if current.ModelID != model.DefaultModelID {
		t.Fatalf("model id = %q, want manual selected %q", current.ModelID, model.DefaultModelID)
	}
}

func TestResolveInvalidManualFallsBackToLanguageDefault(t *testing.T) {
	cfg := config.Default()
	cfg.LanguageMode = config.LanguageModeAuto
	cfg.ModelSelectionMode = config.ModelSelectionModeManual
	cfg.SelectedModelID = "bad-model"

	current := Resolve(cfg, fakeDetector{locale: "en-US"})
	if current.ModelID != model.MoonshineModelID {
		t.Fatalf("model id = %q, want %q", current.ModelID, model.MoonshineModelID)
	}
	if current.FallbackReason == "" {
		t.Fatal("expected fallback reason")
	}
}