package manualsync

import (
	"context"
	"encoding/json"
	"io"
	"net/http"
	"strings"
	"testing"
	"time"

	"modelRT/config"
	"modelRT/constants"
	"modelRT/orm"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

type capturedRequest struct {
	Path        string
	Method      string
	ContentType string
	Payload     Request
}

func TestClientSyncRoutesAndMapsDataSources(t *testing.T) {
	cl3611Requests := make(chan capturedRequest, 2)
	protocol104Requests := make(chan capturedRequest, 1)
	client, err := NewClient(config.ManualSyncConfig{
		ProtocolCL3611URL: "http://cl3611.test",
		Protocol104URL:    "http://protocol104.test",
		APIPath:           "/api/manual",
		Timeout:           time.Second,
	})
	require.NoError(t, err)
	client.httpClient.Transport = roundTripFunc(func(request *http.Request) (*http.Response, error) {
		var payload Request
		require.NoError(t, json.NewDecoder(request.Body).Decode(&payload))
		captured := capturedRequest{
			Path:        request.URL.Path,
			Method:      request.Method,
			ContentType: request.Header.Get("Content-Type"),
			Payload:     payload,
		}
		if request.URL.Host == "cl3611.test" {
			cl3611Requests <- captured
		} else {
			protocol104Requests <- captured
		}
		return httpResponse(http.StatusNoContent, ""), nil
	})

	tests := []struct {
		name       string
		dataSource orm.JSONMap
		requests   <-chan capturedRequest
		wantTarget Target
	}{
		{
			name: "CL3611 phasor",
			dataSource: orm.JSONMap{
				"type": 1,
				"io_address": map[string]any{
					"dtype": 1, "station": "001", "device": "ssu001",
					"channel": "TM1", "option": "RMS",
				},
			},
			requests: cl3611Requests,
			wantTarget: Target{
				Type: 1, Station: "001", MainPos: "ssu001", SubPos: "TM1", Option: "RMS",
			},
		},
		{
			name: "CL3611 sample",
			dataSource: orm.JSONMap{
				"type": 1,
				"io_address": map[string]any{
					"dtype": 2, "station": "002", "device": "ssu002",
					"channel": "TS01", "option": "ignored",
				},
			},
			requests: cl3611Requests,
			wantTarget: Target{
				Type: 2, Station: "002", MainPos: "ssu002", SubPos: "TS01", Option: "",
			},
		},
		{
			name: "104",
			dataSource: orm.JSONMap{
				"type": 2,
				"io_address": map[string]any{
					"station": "station000", "packet": 10, "offset": 35,
				},
			},
			requests: protocol104Requests,
			wantTarget: Target{
				Type: 3, Station: "station000", MainPos: "10", SubPos: "35", Option: "",
			},
		},
	}

	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			err := client.Sync(context.Background(), test.dataSource, constants.MeasurementModeAutomatic, nil)
			require.NoError(t, err)
			captured := <-test.requests
			assert.Equal(t, http.MethodPost, captured.Method)
			assert.Equal(t, "/api/manual", captured.Path)
			assert.Equal(t, "application/json", captured.ContentType)
			assert.Equal(t, constants.MeasurementModeAutomatic, captured.Payload.Mode)
			assert.Nil(t, captured.Payload.Data)
			assert.Equal(t, test.wantTarget, captured.Payload.Target)
		})
	}
}

func TestClientSyncIncludesManualValueData(t *testing.T) {
	requests := make(chan capturedRequest, 1)
	client, err := NewClient(config.ManualSyncConfig{
		ProtocolCL3611URL: "http://cl3611.test",
		Protocol104URL:    "http://protocol104.test",
		APIPath:           "api/manual",
		Timeout:           time.Second,
	})
	require.NoError(t, err)
	client.httpClient.Transport = captureTransport(t, requests)

	sample := SyntheticData{Time: 1736305467506000000, Value: 1.25}
	err = client.Sync(context.Background(), orm.JSONMap{
		"type": 2,
		"io_address": map[string]any{
			"station": "station000", "packet": 1, "offset": 2,
		},
	}, constants.MeasurementModeManual, &sample)
	require.NoError(t, err)
	captured := <-requests
	assert.Equal(t, constants.MeasurementModeManual, captured.Payload.Mode)
	assert.Equal(t, []SyntheticData{sample}, captured.Payload.Data)
}

func TestClientSyncRejectsInvalidDataSources(t *testing.T) {
	client, err := NewClient(config.ManualSyncConfig{
		ProtocolCL3611URL: "http://cl3611.test",
		Protocol104URL:    "http://protocol104.test",
		APIPath:           "/api/manual",
		Timeout:           time.Second,
	})
	require.NoError(t, err)
	client.httpClient.Transport = roundTripFunc(func(*http.Request) (*http.Response, error) {
		t.Fatal("invalid data source must not call endpoint")
		return nil, nil
	})

	tests := []struct {
		name       string
		dataSource orm.JSONMap
		wantError  string
	}{
		{name: "unsupported type", dataSource: orm.JSONMap{"type": 3, "io_address": map[string]any{"station": "s"}}, wantError: "unsupported"},
		{name: "invalid dtype", dataSource: orm.JSONMap{"type": 1, "io_address": map[string]any{"dtype": 3, "station": "s", "device": "d", "channel": "c"}}, wantError: "dtype"},
		{name: "missing station", dataSource: orm.JSONMap{"type": 2, "io_address": map[string]any{"packet": 1, "offset": 2}}, wantError: "station"},
		{name: "fractional packet", dataSource: orm.JSONMap{"type": 2, "io_address": map[string]any{"station": "s", "packet": 1.5, "offset": 2}}, wantError: "packet"},
	}
	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			err := client.Sync(context.Background(), test.dataSource, constants.MeasurementModeManual, nil)
			require.Error(t, err)
			assert.Contains(t, err.Error(), test.wantError)
		})
	}
}

func TestClientSyncReturnsNonSuccessResponse(t *testing.T) {
	client, err := NewClient(config.ManualSyncConfig{
		ProtocolCL3611URL: "http://cl3611.test",
		Protocol104URL:    "http://protocol104.test",
		APIPath:           "/api/manual",
		Timeout:           time.Second,
	})
	require.NoError(t, err)
	client.httpClient.Transport = roundTripFunc(func(*http.Request) (*http.Response, error) {
		return httpResponse(http.StatusServiceUnavailable, "downstream unavailable"), nil
	})

	err = client.Sync(context.Background(), orm.JSONMap{
		"type": 2,
		"io_address": map[string]any{
			"station": "s", "packet": 1, "offset": 2,
		},
	}, constants.MeasurementModeManual, nil)
	require.Error(t, err)
	assert.Contains(t, err.Error(), "Service Unavailable")
	assert.Contains(t, err.Error(), "downstream unavailable")
}

func TestNewClientValidatesConfiguration(t *testing.T) {
	_, err := NewClient(config.ManualSyncConfig{})
	require.Error(t, err)
	assert.Contains(t, err.Error(), "timeout")

	_, err = NewClient(config.ManualSyncConfig{
		ProtocolCL3611URL: "127.0.0.1:9001",
		Protocol104URL:    "http://127.0.0.1:9002",
		APIPath:           "/api/manual",
		Timeout:           time.Second,
	})
	require.Error(t, err)
	assert.Contains(t, err.Error(), "invalid protocol CL3611 URL")
}

type roundTripFunc func(*http.Request) (*http.Response, error)

func (roundTrip roundTripFunc) RoundTrip(request *http.Request) (*http.Response, error) {
	return roundTrip(request)
}

func captureTransport(t *testing.T, requests chan<- capturedRequest) http.RoundTripper {
	t.Helper()
	return roundTripFunc(func(request *http.Request) (*http.Response, error) {
		var payload Request
		require.NoError(t, json.NewDecoder(request.Body).Decode(&payload))
		requests <- capturedRequest{
			Path:        request.URL.Path,
			Method:      request.Method,
			ContentType: request.Header.Get("Content-Type"),
			Payload:     payload,
		}
		return httpResponse(http.StatusNoContent, ""), nil
	})
}

func httpResponse(status int, body string) *http.Response {
	return &http.Response{
		StatusCode: status,
		Status:     http.StatusText(status),
		Body:       io.NopCloser(strings.NewReader(body)),
		Header:     make(http.Header),
	}
}