package sqlserverflexbeta

import (
	"context"
	_ "embed"
	"fmt"
	"strings"
	"time"

	"github.com/hashicorp/terraform-plugin-framework/path"
	"github.com/hashicorp/terraform-plugin-framework/resource"
	"github.com/hashicorp/terraform-plugin-framework/resource/identityschema"
	"github.com/hashicorp/terraform-plugin-framework/types"
	"github.com/hashicorp/terraform-plugin-log/tflog"
	"github.com/stackitcloud/stackit-sdk-go/core/config"
	"tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/conversion"
	wait "tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/wait/sqlserverflexbeta"

	"tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/pkg_gen/sqlserverflexbeta"

	"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"

	sqlserverflexbetaResGen "tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/services/sqlserverflexbeta/database/resources_gen"
)

var (
	_ resource.Resource                = &databaseResource{}
	_ resource.ResourceWithConfigure   = &databaseResource{}
	_ resource.ResourceWithImportState = &databaseResource{}
	_ resource.ResourceWithModifyPlan  = &databaseResource{}
	_ resource.ResourceWithIdentity    = &databaseResource{}
)

func NewDatabaseResource() resource.Resource {
	return &databaseResource{}
}

// resourceModel describes the resource data model.
type resourceModel = sqlserverflexbetaResGen.DatabaseModel

type databaseResource struct {
	client       *sqlserverflexbeta.APIClient
	providerData core.ProviderData
}

type DatabaseResourceIdentityModel struct {
	ProjectID    types.String `tfsdk:"project_id"`
	Region       types.String `tfsdk:"region"`
	InstanceID   types.String `tfsdk:"instance_id"`
	DatabaseName types.String `tfsdk:"database_name"`
}

func (r *databaseResource) Metadata(
	ctx context.Context,
	req resource.MetadataRequest,
	resp *resource.MetadataResponse,
) {
	resp.TypeName = req.ProviderTypeName + "_sqlserverflexbeta_database"
}

//go:embed planModifiers.yaml
var modifiersFileByte []byte

func (r *databaseResource) Schema(ctx context.Context, req resource.SchemaRequest, resp *resource.SchemaResponse) {

	s := sqlserverflexbetaResGen.DatabaseResourceSchema(ctx)

	fields, err := utils.ReadModifiersConfig(modifiersFileByte)
	if err != nil {
		resp.Diagnostics.AddError("error during read modifiers config file", err.Error())
		return
	}

	err = utils.AddPlanModifiersToResourceSchema(fields, &s)
	if err != nil {
		resp.Diagnostics.AddError("error adding plan modifiers", err.Error())
		return
	}
	resp.Schema = s
}

func (r *databaseResource) IdentitySchema(
	_ context.Context,
	_ resource.IdentitySchemaRequest,
	resp *resource.IdentitySchemaResponse,
) {
	resp.IdentitySchema = identityschema.Schema{
		Attributes: map[string]identityschema.Attribute{
			"project_id": identityschema.StringAttribute{
				RequiredForImport: true, // must be set during import by the practitioner
			},
			"region": identityschema.StringAttribute{
				RequiredForImport: true, // can be defaulted by the provider configuration
			},
			"instance_id": identityschema.StringAttribute{
				RequiredForImport: true, // can be defaulted by the provider configuration
			},
			"database_name": identityschema.StringAttribute{
				RequiredForImport: true, // can be defaulted by the provider configuration
			},
		},
	}
}

// Configure adds the provider configured client to the resource.
func (r *databaseResource) Configure(
	ctx context.Context,
	req resource.ConfigureRequest,
	resp *resource.ConfigureResponse,
) {
	var ok bool
	r.providerData, ok = conversion.ParseProviderData(ctx, req.ProviderData, &resp.Diagnostics)
	if !ok {
		return
	}

	apiClientConfigOptions := []config.ConfigurationOption{
		config.WithCustomAuth(r.providerData.RoundTripper),
		utils.UserAgentConfigOption(r.providerData.Version),
	}
	if r.providerData.SQLServerFlexCustomEndpoint != "" {
		apiClientConfigOptions = append(
			apiClientConfigOptions,
			config.WithEndpoint(r.providerData.SQLServerFlexCustomEndpoint),
		)
	} else {
		apiClientConfigOptions = append(apiClientConfigOptions, config.WithRegion(r.providerData.GetRegion()))
	}
	apiClient, err := sqlserverflexbeta.NewAPIClient(apiClientConfigOptions...)
	if err != nil {
		resp.Diagnostics.AddError(
			"Error configuring API client",
			fmt.Sprintf(
				"Configuring client: %v. This is an error related to the provider configuration, not to the resource configuration",
				err,
			),
		)
		return
	}
	r.client = apiClient
	tflog.Info(ctx, "sqlserverflexbeta.Database client configured")
}

func (r *databaseResource) Create(ctx context.Context, req resource.CreateRequest, resp *resource.CreateResponse) {
	var data resourceModel
	createErr := "DB create error"

	// Read Terraform plan data into the model
	resp.Diagnostics.Append(req.Plan.Get(ctx, &data)...)

	if resp.Diagnostics.HasError() {
		return
	}

	// Read identity data
	var identityData DatabaseResourceIdentityModel
	resp.Diagnostics.Append(req.Identity.Get(ctx, &identityData)...)
	if resp.Diagnostics.HasError() {
		return
	}

	ctx = core.InitProviderContext(ctx)

	projectId := identityData.ProjectID.ValueString()
	region := identityData.Region.ValueString()
	instanceId := identityData.InstanceID.ValueString()
	ctx = tflog.SetField(ctx, "project_id", projectId)
	ctx = tflog.SetField(ctx, "region", region)
	ctx = tflog.SetField(ctx, "instance_id", instanceId)

	databaseName := identityData.DatabaseName.ValueString()
	ctx = tflog.SetField(ctx, "database_name", databaseName)

	payLoad := sqlserverflexbeta.CreateDatabaseRequestPayload{
		Collation:     data.Collation.ValueStringPointer(),
		Compatibility: data.Compatibility.ValueInt64Pointer(),
		Name:          data.Name.ValueStringPointer(),
		Owner:         data.Owner.ValueStringPointer(),
	}

	createResp, err := r.client.CreateDatabaseRequest(ctx, projectId, region, instanceId).
		CreateDatabaseRequestPayload(payLoad).
		Execute()
	if err != nil {
		core.LogAndAddError(
			ctx,
			&resp.Diagnostics,
			createErr,
			fmt.Sprintf("Calling API: %v", err),
		)
		return
	}

	ctx = core.LogResponse(ctx)
	createId, ok := createResp.GetIdOk()
	if !ok {
		core.LogAndAddError(
			ctx,
			&resp.Diagnostics,
			createErr,
			fmt.Sprintf("Calling API: %v", err),
		)
	}

	waitResp, err := wait.CreateDatabaseWaitHandler(
		ctx,
		r.client,
		projectId,
		instanceId,
		region,
		databaseName,
	).SetSleepBeforeWait(
		30 * time.Second,
	).SetTimeout(
		15 * time.Minute,
	).WaitWithContext(ctx)
	if err != nil {
		core.LogAndAddError(
			ctx,
			&resp.Diagnostics,
			createErr,
			fmt.Sprintf("Database creation waiting: %v", err),
		)
		return
	}

	if waitResp.Id == nil {
		core.LogAndAddError(
			ctx,
			&resp.Diagnostics,
			createErr,
			"Database creation waiting: returned id is nil",
		)
		return
	}

	if *waitResp.Id != createId {
		core.LogAndAddError(
			ctx,
			&resp.Diagnostics,
			createErr,
			"Database creation waiting: returned id is different",
		)
		return
	}

	if *waitResp.Owner != data.Owner.ValueString() {
		core.LogAndAddError(
			ctx,
			&resp.Diagnostics,
			createErr,
			"Database creation waiting: returned owner is different",
		)
		return
	}

	if *waitResp.Name != data.Name.ValueString() {
		core.LogAndAddError(
			ctx,
			&resp.Diagnostics,
			createErr,
			"Database creation waiting: returned name is different",
		)
		return
	}

	data.Id = types.Int64PointerValue(waitResp.Id)
	data.Name = types.StringPointerValue(waitResp.Name)

	// Save data into Terraform state
	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)

	tflog.Info(ctx, "sqlserverflexbeta.Database created")
}

func (r *databaseResource) Read(ctx context.Context, req resource.ReadRequest, resp *resource.ReadResponse) {
	var data resourceModel
	readErr := "[Database Read]"

	// Read Terraform prior state data into the model
	resp.Diagnostics.Append(req.State.Get(ctx, &data)...)
	if resp.Diagnostics.HasError() {
		return
	}

	// Read identity data
	var identityData DatabaseResourceIdentityModel
	resp.Diagnostics.Append(req.Identity.Get(ctx, &identityData)...)
	if resp.Diagnostics.HasError() {
		return
	}

	ctx = core.InitProviderContext(ctx)

	projectId := identityData.ProjectID.ValueString()
	region := identityData.Region.ValueString()
	ctx = tflog.SetField(ctx, "project_id", projectId)
	ctx = tflog.SetField(ctx, "region", region)

	instanceId := identityData.InstanceID.ValueString()
	ctx = tflog.SetField(ctx, "instance_id", instanceId)

	dbName := identityData.DatabaseName.ValueString()
	ctx = tflog.SetField(ctx, "database_name", dbName)

	getResp, err := r.client.GetDatabaseRequest(ctx, projectId, region, instanceId, dbName).Execute()
	if err != nil {
		core.LogAndAddError(
			ctx,
			&resp.Diagnostics,
			readErr,
			fmt.Sprintf("Calling API: %v", err),
		)
		return
	}

	ctx = core.LogResponse(ctx)

	data.Id = types.Int64Value(getResp.GetId())
	data.Owner = types.StringValue(getResp.GetOwner())
	data.Name = types.StringValue(getResp.GetName())
	data.DatabaseName = types.StringValue(getResp.GetName())
	data.CollationName = types.StringValue(getResp.GetCollationName())
	data.CompatibilityLevel = types.Int64Value(getResp.GetCompatibilityLevel())

	// Save updated data into Terraform state
	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
	tflog.Info(ctx, "sqlserverflexbeta.Database read")
}

func (r *databaseResource) Update(ctx context.Context, req resource.UpdateRequest, resp *resource.UpdateResponse) {
	var data resourceModel

	// Read Terraform prior state data into the model
	resp.Diagnostics.Append(req.State.Get(ctx, &data)...)
	if resp.Diagnostics.HasError() {
		return
	}

	// Read identity data
	var identityData DatabaseResourceIdentityModel
	resp.Diagnostics.Append(req.Identity.Get(ctx, &identityData)...)
	if resp.Diagnostics.HasError() {
		return
	}

	ctx = core.InitProviderContext(ctx)

	projectId := identityData.ProjectID.ValueString()
	region := identityData.Region.ValueString()
	ctx = tflog.SetField(ctx, "project_id", projectId)
	ctx = tflog.SetField(ctx, "region", region)

	// Todo: Update API call logic

	// Save updated data into Terraform state
	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)

	tflog.Info(ctx, "sqlserverflexbeta.Database updated")
}

func (r *databaseResource) Delete(ctx context.Context, req resource.DeleteRequest, resp *resource.DeleteResponse) {
	var data resourceModel

	// Read Terraform prior state data into the model
	resp.Diagnostics.Append(req.State.Get(ctx, &data)...)
	if resp.Diagnostics.HasError() {
		return
	}

	// Read identity data
	var identityData DatabaseResourceIdentityModel
	resp.Diagnostics.Append(req.Identity.Get(ctx, &identityData)...)
	if resp.Diagnostics.HasError() {
		return
	}

	ctx = core.InitProviderContext(ctx)

	projectId := identityData.ProjectID.ValueString()
	region := identityData.Region.ValueString()
	ctx = tflog.SetField(ctx, "project_id", projectId)
	ctx = tflog.SetField(ctx, "region", region)

	// Todo: Delete API call logic

	tflog.Info(ctx, "sqlserverflexbeta.Database deleted")
}

// ModifyPlan implements resource.ResourceWithModifyPlan.
// Use the modifier to set the effective region in the current plan.
func (r *databaseResource) ModifyPlan(
	ctx context.Context,
	req resource.ModifyPlanRequest,
	resp *resource.ModifyPlanResponse,
) { // nolint:gocritic // function signature required by Terraform

	// skip initial empty configuration to avoid follow-up errors
	if req.Config.Raw.IsNull() {
		return
	}

	var configModel sqlserverflexbetaResGen.DatabaseModel
	resp.Diagnostics.Append(req.Config.Get(ctx, &configModel)...)
	if resp.Diagnostics.HasError() {
		return
	}

	var planModel sqlserverflexbetaResGen.DatabaseModel
	resp.Diagnostics.Append(req.Plan.Get(ctx, &planModel)...)
	if resp.Diagnostics.HasError() {
		return
	}

	utils.AdaptRegion(ctx, configModel.Region, &planModel.Region, r.providerData.GetRegion(), resp)
	if resp.Diagnostics.HasError() {
		return
	}

	var identityModel DatabaseResourceIdentityModel
	identityModel.ProjectID = planModel.ProjectId
	identityModel.Region = planModel.Region

	if !planModel.InstanceId.IsNull() && !planModel.InstanceId.IsUnknown() {
		identityModel.InstanceID = planModel.InstanceId
	}

	if !planModel.Name.IsNull() && !planModel.Name.IsUnknown() {
		identityModel.DatabaseName = planModel.Name
	}

	resp.Diagnostics.Append(resp.Identity.Set(ctx, identityModel)...)
	if resp.Diagnostics.HasError() {
		return
	}

	resp.Diagnostics.Append(resp.Plan.Set(ctx, planModel)...)
	if resp.Diagnostics.HasError() {
		return
	}
}

// ImportState imports a resource into the Terraform state on success.
// The expected format of the resource import identifier is: project_id,zone_id,record_set_id
func (r *databaseResource) ImportState(
	ctx context.Context,
	req resource.ImportStateRequest,
	resp *resource.ImportStateResponse,
) {
	ctx = core.InitProviderContext(ctx)

	if req.ID != "" {
		idParts := strings.Split(req.ID, core.Separator)

		if len(idParts) != 4 || idParts[0] == "" || idParts[1] == "" || idParts[2] == "" || idParts[3] == "" {
			core.LogAndAddError(
				ctx, &resp.Diagnostics,
				"Error importing database",
				fmt.Sprintf(
					"Expected import identifier with format: [project_id],[region],[instance_id],[database_name]  Got: %q",
					req.ID,
				),
			)
			return
		}

		resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("project_id"), idParts[0])...)
		resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("region"), idParts[1])...)
		resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("instance_id"), idParts[2])...)
		resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("database_name"), idParts[3])...)

		var identityData DatabaseResourceIdentityModel
		identityData.ProjectID = types.StringValue(idParts[0])
		identityData.Region = types.StringValue(idParts[1])
		identityData.InstanceID = types.StringValue(idParts[2])
		identityData.DatabaseName = types.StringValue(idParts[3])

		resp.Diagnostics.Append(resp.Identity.Set(ctx, &identityData)...)
		if resp.Diagnostics.HasError() {
			return
		}

		tflog.Info(ctx, "Sqlserverflexbeta database state imported")
		return
	}

	// If no ID is provided, attempt to read identity attributes from the import configuration
	var identityData DatabaseResourceIdentityModel
	resp.Diagnostics.Append(req.Identity.Get(ctx, &identityData)...)
	if resp.Diagnostics.HasError() {
		return
	}

	projectId := identityData.ProjectID.ValueString()
	region := identityData.Region.ValueString()
	instanceId := identityData.InstanceID.ValueString()
	databaseName := identityData.DatabaseName.ValueString()

	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("project_id"), projectId)...)
	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("region"), region)...)
	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("instance_id"), instanceId)...)
	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("database_name"), databaseName)...)

	tflog.Info(ctx, "Sqlserverflexbeta database state imported")
}