package affinitygroup

import (
	"context"
	"fmt"
	"net/http"
	"regexp"

	"github.com/stackitcloud/terraform-provider-stackit/stackit/internal/core"
	"github.com/stackitcloud/terraform-provider-stackit/stackit/internal/features"
	"github.com/stackitcloud/terraform-provider-stackit/stackit/internal/validate"

	"github.com/hashicorp/terraform-plugin-framework-validators/listvalidator"
	"github.com/hashicorp/terraform-plugin-framework-validators/stringvalidator"
	"github.com/hashicorp/terraform-plugin-framework/datasource"
	"github.com/hashicorp/terraform-plugin-framework/datasource/schema"
	"github.com/hashicorp/terraform-plugin-framework/schema/validator"
	"github.com/hashicorp/terraform-plugin-framework/types"
	"github.com/hashicorp/terraform-plugin-log/tflog"
	"github.com/stackitcloud/stackit-sdk-go/core/config"
	"github.com/stackitcloud/stackit-sdk-go/core/oapierror"
	"github.com/stackitcloud/stackit-sdk-go/services/iaas"
)

var affinityGroupDataSourceBetaCheckDone bool

var (
	_ datasource.DataSource              = &affinityGroupDatasource{}
	_ datasource.DataSourceWithConfigure = &affinityGroupDatasource{}
)

func NewAffinityGroupDatasource() datasource.DataSource {
	return &affinityGroupDatasource{}
}

type affinityGroupDatasource struct {
	client *iaas.APIClient
}

func (d *affinityGroupDatasource) Configure(ctx context.Context, req datasource.ConfigureRequest, resp *datasource.ConfigureResponse) {
	// Prevent panic if the provider has not been configured.
	if req.ProviderData == nil {
		return
	}

	providerData, ok := req.ProviderData.(core.ProviderData)
	if !ok {
		core.LogAndAddError(ctx, &resp.Diagnostics, "Error configuring API client", fmt.Sprintf("Expected configure type stackit.ProviderData, got %T", req.ProviderData))
		return
	}

	if !affinityGroupDataSourceBetaCheckDone {
		features.CheckBetaResourcesEnabled(ctx, &providerData, &resp.Diagnostics, "stackit_affinity_group", "data source")
		if resp.Diagnostics.HasError() {
			return
		}
		affinityGroupDataSourceBetaCheckDone = true
	}

	var apiClient *iaas.APIClient
	var err error
	if providerData.IaaSCustomEndpoint != "" {
		ctx = tflog.SetField(ctx, "iaas_custom_endpoint", providerData.IaaSCustomEndpoint)
		apiClient, err = iaas.NewAPIClient(
			config.WithCustomAuth(providerData.RoundTripper),
			config.WithEndpoint(providerData.IaaSCustomEndpoint),
		)
	} else {
		apiClient, err = iaas.NewAPIClient(
			config.WithCustomAuth(providerData.RoundTripper),
			config.WithRegion(providerData.Region),
		)
	}

	if err != nil {
		core.LogAndAddError(ctx, &resp.Diagnostics, "Error configuring API client", fmt.Sprintf("Configuring client: %v. This is an error related to the provider configuration, not to the resource configuratio", err))
		return
	}

	d.client = apiClient
	tflog.Info(ctx, "iaas client configured")
}

func (d *affinityGroupDatasource) Metadata(_ context.Context, req datasource.MetadataRequest, resp *datasource.MetadataResponse) {
	resp.TypeName = req.ProviderTypeName + "_affinity_group"
}

func (d *affinityGroupDatasource) Schema(_ context.Context, _ datasource.SchemaRequest, resp *datasource.SchemaResponse) {
	descriptionMain := "Affinity Group schema. Must have a `region` specified in the provider configuration."
	resp.Schema = schema.Schema{
		Description:         descriptionMain,
		MarkdownDescription: descriptionMain,
		Attributes: map[string]schema.Attribute{
			"id": schema.StringAttribute{
				Description: "Terraform's internal resource identifier. It is structured as \"`project_id`,`affinity_group_id`\".",
				Computed:    true,
			},
			"project_id": schema.StringAttribute{
				Description: "STACKIT Project ID to which the affinity group is associated.",
				Required:    true,
				Validators: []validator.String{
					validate.UUID(),
					validate.NoSeparator(),
				},
			},
			"affinity_group_id": schema.StringAttribute{
				Description: "The affinity group ID.",
				Required:    true,
				Validators: []validator.String{
					validate.UUID(),
					validate.NoSeparator(),
				},
			},
			"name": schema.StringAttribute{
				Description: "The name of the affinity group.",
				Computed:    true,
				Validators: []validator.String{
					stringvalidator.LengthAtLeast(1),
					stringvalidator.LengthAtMost(63),
					stringvalidator.RegexMatches(
						regexp.MustCompile(`^[A-Za-z0-9]+((-|_|\s|\.)[A-Za-z0-9]+)*$`),
						"must match expression"),
				},
			},
			"policy": schema.StringAttribute{
				Description: "The policy of the affinity group.",
				Computed:    true,
			},
			"members": schema.ListAttribute{
				Description: descriptionMain,
				Computed:    true,
				ElementType: types.StringType,
				Validators: []validator.List{
					listvalidator.ValueStringsAre(
						validate.UUID(),
					),
				},
			},
		},
	}
}

func (d *affinityGroupDatasource) Read(ctx context.Context, req datasource.ReadRequest, resp *datasource.ReadResponse) { // nolint:gocritic // function signature required by Terraform
	var model Model
	diags := req.Config.Get(ctx, &model)
	resp.Diagnostics.Append(diags...)
	if resp.Diagnostics.HasError() {
		return
	}
	projectId := model.ProjectId.ValueString()
	affinityGroupId := model.AffinityGroupId.ValueString()
	ctx = tflog.SetField(ctx, "project_id", projectId)
	ctx = tflog.SetField(ctx, "affinity_group_id", affinityGroupId)

	affinityGroupResp, err := d.client.GetAffinityGroupExecute(ctx, projectId, affinityGroupId)
	if err != nil {
		oapiErr, ok := err.(*oapierror.GenericOpenAPIError) //nolint:errorlint //complaining that error.As should be used to catch wrapped errors, but this error should not be wrapped
		if ok && oapiErr.StatusCode == http.StatusNotFound {
			resp.State.RemoveResource(ctx)
			return
		}
		core.LogAndAddError(ctx, &resp.Diagnostics, "Error reading affinity group", fmt.Sprintf("Call API: %v", err))
		return
	}

	err = mapFields(ctx, affinityGroupResp, &model)
	if err != nil {
		core.LogAndAddError(ctx, &resp.Diagnostics, "Error reading affinity group", fmt.Sprintf("Processing API payload: %v", err))
	}

	diags = resp.State.Set(ctx, model)
	resp.Diagnostics.Append(diags...)
	if resp.Diagnostics.HasError() {
		return
	}
	tflog.Info(ctx, "Affinity group read")
}