package todov1

import (
	"context"
	"errors"
	"log/slog"
	"strconv"

	"connectrpc.com/connect"
	"git.kocoder.xyz/kocoded/vt/fx"
	todov1 "git.kocoder.xyz/kocoded/vt/gen/todo/v1"
	"git.kocoder.xyz/kocoded/vt/gen/todo/v1/todov1connect"
	"git.kocoder.xyz/kocoded/vt/interceptors"
	"git.kocoder.xyz/kocoded/vt/query"
	"gorm.io/gen/field"
	"gorm.io/gorm"
)

func NewTodoRoute(db *gorm.DB, logger *slog.Logger, oidcInterceptor *interceptors.AuthenticationInterceptor) fx.Handler {
	path, handler := todov1connect.NewTodoServiceHandler(&todoService{logger: logger, db: db}, connect.WithInterceptors(oidcInterceptor))

	return fx.NewRoute(path, handler)
}

type todoService struct {
	logger *slog.Logger
	db     *gorm.DB
}

func (ts *todoService) GetTodo(ctx context.Context, req *todov1.GetTodosRequest) (*todov1.GetTodosResponse, error) {
	s, ok := interceptors.SessionFromContext(ctx)
	if !ok {
		return nil, connect.NewError(connect.CodeUnauthenticated, errors.New("No session set."))
	}

	t := query.Use(ts.db).Task
	res, err := t.Where(t.ID.Eq(uint(req.Id))).Where(t.MandantID.Eq(s.MandantId)).First()
	if err != nil {
		return nil, connect.NewError(connect.CodeInternal, err)
	}

	tres := &todov1.GetTodosResponse{
		Id:          int64(res.ID),
		Title:       res.Titel,
		Description: res.Description,
		Status:      todov1.Status(res.Status),
	}

	return tres, nil

	// return &todov1.GetTodosResponse{
	// 	Id:          1,
	// 	Title:       "Sample Todo",
	// 	Description: "This is a sample todo item.",
	// 	Status:      todov1.Status_Doing,
	// }, nil
}

func (ts *todoService) ContributeToQuery(f *todov1.Filter, q query.ITaskDo) query.ITaskDo {
	t := query.Use(ts.db).Task

	switch f.Field {
	case todov1.Field_FieldDescription, todov1.Field_FieldTitle:
		var field field.String
		if f.Field == todov1.Field_FieldDescription {
			field = t.Description
		} else {
			field = t.Titel
		}
		switch f.Operation {
		case todov1.Operation_Equals:
			q = q.Where(field.Eq(f.Value))
		case todov1.Operation_NotEquals:
			q = q.Where(field.Neq(f.Value))
		case todov1.Operation_GreaterThan:
			q = q.Where(field.Gt(f.Value))
		case todov1.Operation_LessThan:
			q = q.Where(field.Lt(f.Value))
		case todov1.Operation_Like:
			q = q.Where(field.Like(f.Value))
		}
	case todov1.Field_FieldId:
		i, err := strconv.Atoi(f.Value)
		if err != nil {
			slog.Warn("Value not an int", "err", err)
			return q
		}
		switch f.Operation {
		case todov1.Operation_Equals:
			q = q.Where(t.ID.Eq(uint(i)))
		case todov1.Operation_NotEquals:
			q = q.Where(t.ID.Neq(uint(i)))
		case todov1.Operation_GreaterThan:
			q = q.Where(t.ID.Gt(uint(i)))
		case todov1.Operation_LessThan:
			q = q.Where(t.ID.Lt(uint(i)))
		}
	case todov1.Field_FieldStatus:
		i, err := strconv.Atoi(f.Value)
		if err != nil {
			slog.Warn("Value not an int", "err", err)
			return q
		}
		switch f.Operation {
		case todov1.Operation_Equals:
			q = q.Where(t.Status.Eq(i))
		case todov1.Operation_NotEquals:
			q = q.Where(t.Status.Neq(i))
		case todov1.Operation_GreaterThan:
			q = q.Where(t.Status.Gt(i))
		case todov1.Operation_LessThan:
			q = q.Where(t.Status.Lt(i))
		}
	default:
		return q
	}
	return q
}

func (ts *todoService) ListTodos(ctx context.Context, req *todov1.ListTodosRequest) (*todov1.ListTodosResponse, error) {
	ts.logger.Info("ListTodos called", "request", req)
	s, ok := interceptors.SessionFromContext(ctx)
	if !ok {
		return nil, connect.NewError(connect.CodeUnauthenticated, errors.New("No session set."))
	}

	t := query.Use(ts.db).Task
	taskQuery := t.Where(t.MandantID.Eq(s.MandantId))

	for _, v := range req.Filters {
		taskQuery = ts.ContributeToQuery(v, taskQuery)
	}

	taskQuery = taskQuery.Limit(int(req.PerPage)).Offset(int(req.Page))
	if req.OrberBy != "" {
		f, ok := t.GetFieldByName(req.OrberBy)
		if ok {
			if !req.Asc {
				taskQuery = taskQuery.Order(f.Desc())
			} else {
				taskQuery = taskQuery.Order(f.Asc())
			}
		}
	} else {
		taskQuery = taskQuery.Order(t.ID.Asc())
	}

	tasks, err := taskQuery.Find()
	if err != nil {
		return nil, err
	}

	taskQuery = t.Where(t.MandantID.Eq(s.MandantId))

	for _, v := range req.Filters {
		taskQuery = ts.ContributeToQuery(v, taskQuery)
	}

	cnt, err := taskQuery.Count()

	if err != nil {
		ts.logger.Info("Counting Todos failed", "request", req, "err", err)
		panic(err)
	}

	data := make([]*todov1.GetTodosResponse, len(tasks))
	for i, p := range tasks {
		data[i] = &todov1.GetTodosResponse{
			Id:          int64(p.ID),
			Title:       p.Titel,
			Description: p.Description,
			Status:      todov1.Status(p.Status),
		}
	}

	return &todov1.ListTodosResponse{
		Data: data,
		Meta: &todov1.Metadata{
			TotalCount: int32(cnt),
		},
	}, nil
}