package postgresflexalpha

import (
	"fmt"
	"strconv"

	"github.com/hashicorp/terraform-plugin-framework/attr"
	"github.com/hashicorp/terraform-plugin-framework/types"
	"github.com/stackitcloud/stackit-sdk-go/services/postgresflex/v3alpha1api"

	"tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/core"
	"tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/utils"
)

// mapDataSourceFields maps API response to data source model, preserving existing ID.
func mapDataSourceFields(userResp *v3alpha1api.GetUserResponse, model *dataSourceModel, region string) error {
	if userResp == nil {
		return fmt.Errorf("response is nil")
	}
	if model == nil {
		return fmt.Errorf("model input is nil")
	}
	user := userResp

	var userID int64
	if model.UserId.ValueInt64() != 0 {
		userID = model.UserId.ValueInt64()
	} else {
		return fmt.Errorf("user id not present")
	}

	model.TerraformID = utils.BuildInternalTerraformId(
		model.ProjectId.ValueString(), region, model.InstanceId.ValueString(), strconv.FormatInt(userID, 10),
	)

	model.UserId = types.Int64Value(userID)
	model.Name = types.StringValue(user.GetName())

	if user.Roles == nil {
		model.Roles = types.List(types.SetNull(types.StringType))
	} else {
		var roles []attr.Value
		for _, role := range user.Roles {
			roles = append(roles, types.StringValue(string(role)))
		}
		rolesSet, diags := types.SetValue(types.StringType, roles)
		if diags.HasError() {
			return fmt.Errorf("failed to map roles: %w", core.DiagsToError(diags))
		}
		model.Roles = types.List(rolesSet)
	}

	model.Id = types.Int64Value(userID)
	model.Region = types.StringValue(region)
	model.Status = types.StringValue(user.GetStatus())
	return nil
}

// toPayloadRoles converts a string slice to the API's role type.
func toPayloadRoles(roles []string) []v3alpha1api.UserRole {
	var userRoles = make([]v3alpha1api.UserRole, 0, len(roles))
	for _, role := range roles {
		userRoles = append(userRoles, v3alpha1api.UserRole(role))
	}
	return userRoles
}

// toUpdatePayload creates an API update payload from the resource model.
func toUpdatePayload(model *resourceModel, roles []string) (
	*v3alpha1api.UpdateUserRequestPayload,
	error,
) {
	if model == nil {
		return nil, fmt.Errorf("nil model")
	}
	if roles == nil {
		return nil, fmt.Errorf("nil roles")
	}

	return &v3alpha1api.UpdateUserRequestPayload{
		Name:  model.Name.ValueStringPointer(),
		Roles: toPayloadRoles(roles),
	}, nil
}

// toCreatePayload creates an API create payload from the resource model.
func toCreatePayload(model *resourceModel, roles []string) (*v3alpha1api.CreateUserRequestPayload, error) {
	if model == nil {
		return nil, fmt.Errorf("nil model")
	}
	if roles == nil {
		return nil, fmt.Errorf("nil roles")
	}

	return &v3alpha1api.CreateUserRequestPayload{
		Roles: toPayloadRoles(roles),
		Name:  model.Name.ValueString(),
	}, nil
}

// mapResourceFields maps API response to the resource model, preserving existing ID.
func mapResourceFields(userResp *v3alpha1api.GetUserResponse, model *resourceModel, region string) error {
	if userResp == nil {
		return fmt.Errorf("response is nil")
	}
	if model == nil {
		return fmt.Errorf("model input is nil")
	}
	user := userResp

	var userID int64
	if !model.UserId.IsNull() && !model.UserId.IsUnknown() && model.UserId.ValueInt64() != 0 {
		userID = model.UserId.ValueInt64()
	} else if user.Id != 0 {
		userID = int64(user.Id)
	} else {
		return fmt.Errorf("user id not present")
	}

	model.Id = types.Int64Value(userID)
	model.UserId = types.Int64Value(userID)
	model.Name = types.StringValue(user.Name)

	if user.Roles == nil {
		model.Roles = types.List(types.SetNull(types.StringType))
	} else {
		var roles []attr.Value
		for _, role := range user.Roles {
			roles = append(roles, types.StringValue(string(role)))
		}
		rolesSet, diags := types.SetValue(types.StringType, roles)
		if diags.HasError() {
			return fmt.Errorf("failed to map roles: %w", core.DiagsToError(diags))
		}
		model.Roles = types.List(rolesSet)
	}
	model.Region = types.StringValue(region)
	model.Status = types.StringValue(user.Status)
	return nil
}