package tui

import (
    "testing"

    "ai-agent/internal/config"
)

func TestModelPicker_OpenClose(t *testing.T) {
    t.Run("open_without_model_list_noop", func(t *testing.T) {
        m := newTestModel(t)
        m.openModelPicker()
        if m.overlay == OverlayModelPicker {
            t.Error("should not open picker without model list")
        }
    })
    t.Run("open_with_model_list", func(t *testing.T) {
        m := newTestModel(t)
        m.modelList = []string{"qwen3.5:0.8b", "qwen3.5:2b", "qwen3.5:4b", "qwen3.5:9b"}
        m.model = "qwen3.5:0.8b"
        m.openModelPicker()
        if m.overlay != OverlayModelPicker {
            t.Errorf("expected OverlayModelPicker, got %d", m.overlay)
        }
        if m.modelPickerState == nil {
            t.Fatal("modelPickerState should not be nil")
        }
        if len(m.modelPickerState.Models) == 0 {
            t.Error("should have models in picker")
        }
        if m.modelPickerState.CurrentModel != "qwen3.5:0.8b" {
            t.Errorf("expected current model 'qwen3.5:0.8b', got %q", m.modelPickerState.CurrentModel)
        }
    })
    t.Run("close_resets_state", func(t *testing.T) {
        m := newTestModel(t)
        m.modelList = []string{"qwen3.5:0.8b", "qwen3.5:2b"}
        m.model = "qwen3.5:0.8b"
        m.openModelPicker()
        m.closeModelPicker()
        if m.modelPickerState != nil {
            t.Error("modelPickerState should be nil after close")
        }
        if m.overlay != OverlayNone {
            t.Errorf("overlay should be OverlayNone, got %d", m.overlay)
        }
    })
}

func TestModelPicker_Navigation(t *testing.T) {
    setup := func(t *testing.T) *Model {
        t.Helper()
        m := newTestModel(t)
        m.modelList = []string{"qwen3.5:0.8b", "qwen3.5:2b", "qwen3.5:4b", "qwen3.5:9b"}
        m.model = config.DefaultModels()[0].Name
        m.openModelPicker()
        return m
    }
    t.Run("down_moves_index", func(t *testing.T) {
        m := setup(t)
        updated, _ := m.Update(downKey())
        m = updated.(*Model)
        if m.modelPickerState.List.Index() != 1 {
            t.Errorf("expected index 1, got %d", m.modelPickerState.List.Index())
        }
    })
    t.Run("up_at_zero_stays", func(t *testing.T) {
        m := setup(t)
        updated, _ := m.Update(upKey())
        m = updated.(*Model)
        if m.modelPickerState.List.Index() != 0 {
            t.Errorf("expected index 0, got %d", m.modelPickerState.List.Index())
        }
    })
    t.Run("down_clamped_at_end", func(t *testing.T) {
        m := setup(t)
        lastIdx := len(m.modelPickerState.Models) - 1
        m.modelPickerState.List.Select(lastIdx)
        updated, _ := m.Update(downKey())
        m = updated.(*Model)
        if m.modelPickerState.List.Index() != lastIdx {
            t.Errorf("expected index to stay at end, got %d", m.modelPickerState.List.Index())
        }
    })
    t.Run("esc_closes", func(t *testing.T) {
        m := setup(t)
        updated, _ := m.Update(escKey())
        m = updated.(*Model)
        if m.modelPickerState != nil {
            t.Error("ESC should close picker")
        }
        if m.overlay != OverlayNone {
            t.Errorf("overlay should be OverlayNone, got %d", m.overlay)
        }
    })
}

func TestModelPicker_CtrlM(t *testing.T) {
    t.Run("opens_with_ctrl_m", func(t *testing.T) {
        m := newTestModel(t)
        m.modelList = []string{"qwen3.5:0.8b", "qwen3.5:2b"}
        m.model = "qwen3.5:0.8b"
        m.state = StateIdle
        updated, _ := m.Update(ctrlKey('m'))
        m = updated.(*Model)
        if m.overlay != OverlayModelPicker {
            t.Errorf("ctrl+m should open model picker, got overlay %d", m.overlay)
        }
    })
    t.Run("no_open_when_streaming", func(t *testing.T) {
        m := newTestModel(t)
        m.modelList = []string{"qwen3.5:0.8b"}
        m.model = "qwen3.5:0.8b"
        m.state = StateStreaming
        updated, _ := m.Update(ctrlKey('m'))
        m = updated.(*Model)
        if m.overlay == OverlayModelPicker {
            t.Error("should not open picker when streaming")
        }
    })
}