package builtin

import (
	"context"
	"encoding/json"
	"testing"
)

func TestTodoTool_ReplacesListAndRendersStatus(t *testing.T) {
	tt := &TodoTool{}
	env := testEnv(t)

	in, _ := json.Marshal(map[string]any{
		"items": []map[string]string{
			{"content": "read file", "status": "completed"},
			{"content": "write fix", "status": "in_progress"},
			{"content": "run tests", "status": "pending"},
		},
	})
	res, err := tt.Run(context.Background(), in, env)
	if err != nil {
		t.Fatal(err)
	}
	if res.IsError {
		t.Fatalf("unexpected error: %s", res.ForModel)
	}
	if !contains(res.ForModel, "[x] read file") {
		t.Errorf("expected completed marker, got: %q", res.ForModel)
	}
	if !contains(res.ForModel, "[~] write fix") {
		t.Errorf("expected in_progress marker, got: %q", res.ForModel)
	}
	if !contains(res.ForModel, "[ ] run tests") {
		t.Errorf("expected pending marker, got: %q", res.ForModel)
	}

	ui, ok := res.ForUI.(TodoResult)
	if !ok || len(ui.Items) != 3 {
		t.Errorf("ForUI = %+v, want TodoResult with 3 items", res.ForUI)
	}
}

func TestTodoTool_RejectsInvalidStatus(t *testing.T) {
	tt := &TodoTool{}
	env := testEnv(t)

	in, _ := json.Marshal(map[string]any{
		"items": []map[string]string{{"content": "x", "status": "bogus"}},
	})
	res, err := tt.Run(context.Background(), in, env)
	if err != nil {
		t.Fatal(err)
	}
	if !res.IsError {
		t.Fatal("expected error for invalid status")
	}
}

func TestTodoTool_SecondCallReplacesFirst(t *testing.T) {
	tt := &TodoTool{}
	env := testEnv(t)

	first, _ := json.Marshal(map[string]any{
		"items": []map[string]string{{"content": "a", "status": "pending"}, {"content": "b", "status": "pending"}},
	})
	if _, err := tt.Run(context.Background(), first, env); err != nil {
		t.Fatal(err)
	}

	second, _ := json.Marshal(map[string]any{
		"items": []map[string]string{{"content": "c", "status": "pending"}},
	})
	res, err := tt.Run(context.Background(), second, env)
	if err != nil {
		t.Fatal(err)
	}
	ui := res.ForUI.(TodoResult)
	if len(ui.Items) != 1 || ui.Items[0].Content != "c" {
		t.Errorf("expected list replaced with single item 'c', got: %+v", ui.Items)
	}
}