// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
//  http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.

package main

import (
	"context"
	"reflect"
	"testing"

	"gitlab.com/flimzy/testy"

	kivik "github.com/go-kivik/kivik/v4"
	"github.com/go-kivik/kivik/v4/driver"
)

type testDriver interface {
	WithCtx(context.Context) error
	NoCtx(string) error
	WithOptions(string, driver.Options)
}

type testClient struct{}

func (c *testClient) WithCtx(context.Context) error       { return nil }
func (c *testClient) NoCtx(string) error                  { return nil }
func (c *testClient) WithOptions(string, ...kivik.Option) {}

func TestMethods(t *testing.T) {
	type tst struct {
		input    interface{}
		isClient bool
		expected []*method
		err      string
	}
	tests := testy.NewTable()
	tests.Add("non-struct", tst{
		input: 123,
		err:   "input must be struct",
	})
	tests.Add("wrong field name", tst{
		input: struct{ Y int }{}, // nolint: unused
		err:   "wrapper struct must have a single field: X",
	})
	tests.Add("non-interface", tst{
		input: struct{ X int }{}, // nolint: unused
		err:   "field X must be of type interface",
	})
	tests.Add("testDriver", tst{
		input: struct{ X testDriver }{}, // nolint: unused
		expected: []*method{
			{
				Name:         "NoCtx",
				ReturnsError: true,
				Accepts:      []reflect.Type{typeString},
			},
			{
				Name:           "WithCtx",
				AcceptsContext: true,
				ReturnsError:   true,
			},
			{
				Name:           "WithOptions",
				AcceptsOptions: true,
				Accepts:        []reflect.Type{typeString},
			},
		},
	})
	tests.Add("invalid client", tst{
		input:    struct{ X int }{}, // nolint: unused
		isClient: true,
		err:      "field X must be of type pointer to struct",
	})
	tests.Add("testClient", tst{
		input:    struct{ X testClient }{}, // nolint: unused
		isClient: true,
		err:      "field X must be of type pointer to struct",
	})
	tests.Add("*testClient", tst{
		input:    struct{ X *testClient }{}, // nolint: unused
		isClient: true,
		expected: []*method{
			{
				Name:         "NoCtx",
				ReturnsError: true,
				Accepts:      []reflect.Type{typeString},
			},
			{
				Name:           "WithCtx",
				AcceptsContext: true,
				ReturnsError:   true,
			},
			{
				Name:           "WithOptions",
				AcceptsOptions: true,
				Accepts:        []reflect.Type{typeString},
			},
		},
	})

	tests.Run(t, func(t *testing.T, test tst) {
		result, err := parseMethods(test.input, test.isClient, nil)
		if !testy.ErrorMatches(test.err, err) {
			t.Errorf("Unexpected error: %s", err)
		}
		if d := testy.DiffInterface(test.expected, result); d != nil {
			t.Error(d)
		}
	})
}