/*
Copyright (c) 2019-2021 Digital Energy Cloud Solutions LLC. All Rights Reserved.
Author: Sergey Shubin, <sergey.shubin@digitalenergy.online>, <svs1370@gmail.com>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

/*
This file is part of Terraform (by Hashicorp) provider for Digital Energy Cloud Orchestration
Technology platfom.

Visit https://github.com/rudecs/terraform-provider-decort for full source code package and updates.
*/

package decort

import (
	"encoding/json"
	"fmt"

	// "net/url"

	log "github.com/sirupsen/logrus"

	"github.com/hashicorp/terraform-plugin-sdk/helper/schema"
	// "github.com/hashicorp/terraform-plugin-sdk/helper/validation"
)

// Parse list of all disks from API compute/get into a list of "extra disks" attached to this compute
// Extra disks are all compute disks but a boot disk.
func parseComputeDisksToExtraDisks(disks []DiskRecord) []interface{} {
	// this return value will be used to d.Set("extra_disks",) item of dataSourceCompute schema,
	// which is a simple list of integer disk IDs excluding boot disk ID
	length := len(disks)
	log.Debugf("parseComputeDisksToExtraDisks: called for %d disks", length)

	if length == 0 || (length == 1 && disks[0].Type == "B") {
		// the disk list is empty (which is kind of strange - diskless compute?), or
		// there is only one disk in the list and it is a boot disk;
		// as we skip boot disks, the result will be of 0 length anyway
		return make([]interface{}, 0)
	}

	result := make([]interface{}, length-1)
	idx := 0
	for _, value := range disks {
		if value.Type == "B" {
			// skip boot disk when iterating over the list of disks
			continue
		}

		result[idx] = value.ID
		idx++
	}

	return result
}

// NOTE: this is a legacy function, which is not used as of rc-1.10
// Use "parseComputeDisksToExtraDisks" instead
func parseComputeDisks(disks []DiskRecord) []interface{} {
	// Return value was designed to d.Set("disks",) item of dataSourceCompute schema
	// However, this item was excluded from the schema as it is not directly
	// managed through Terraform
	length := len(disks)
	log.Debugf("parseComputeDisks: called for %d disks", length)

	/*
		if length == 1 && disks[0].Type == "B" {
			// there is only one disk in the list and it is a boot disk
			// as we skip boot disks, the result will be of 0 lenght
			length = 0
		}
	*/

	result := []interface{}{}

	if length == 0 {
		return result
	}

	for _, value := range disks {
		/*
			if value.Type == "B" {
				// skip boot disk when parsing the list of disks
				continue
			}
		*/
		elem := make(map[string]interface{})
		// keys in this map should correspond to the Schema definition
		// as returned by dataSourceDiskSchemaMake()
		elem["name"] = value.Name
		elem["disk_id"] = value.ID
		elem["account_id"] = value.AccountID
		elem["account_name"] = value.AccountName
		elem["description"] = value.Desc
		elem["image_id"] = value.ImageID
		elem["size"] = value.SizeMax
		elem["type"] = value.Type
		elem["sep_id"] = value.SepID
		elem["sep_type"] = value.SepType
		elem["pool"] = value.Pool
		// elem["status"] = value.Status
		// elem["tech_status"] = value.TechStatus
		elem["compute_id"] = value.ComputeID

		result = append(result, elem)
	}

	return result
}

func parseBootDiskSize(disks []DiskRecord) int {
	// this return value will be used to d.Set("boot_disk_size",) item of dataSourceCompute schema
	if len(disks) == 0 {
		return 0
	}

	for _, value := range disks {
		if value.Type == "B" {
			return value.SizeMax
		}
	}

	return 0
}

func parseBootDiskId(disks []DiskRecord) uint {
	// this return value will be used to d.Set("boot_disk_id",) item of dataSourceCompute schema
	if len(disks) == 0 {
		return 0
	}

	for _, value := range disks {
		if value.Type == "B" {
			return value.ID
		}
	}

	return 0
}

// Parse the list of interfaces from compute/get response into a list of networks
// attached to this compute
func parseComputeInterfacesToNetworks(ifaces []InterfaceRecord) []interface{} {
	// return value will be used to d.Set("network") item of dataSourceCompute schema
	length := len(ifaces)
	log.Debugf("parseComputeInterfacesToNetworks: called for %d ifaces", length)

	result := []interface{}{}

	for _, value := range ifaces {
		elem := make(map[string]interface{})
		// Keys in this map should correspond to the Schema definition
		// as returned by networkSubresourceSchemaMake()
		elem["net_id"] = value.NetID
		elem["net_type"] = value.NetType
		elem["ip_address"] = value.IPAddress
		elem["mac"] = value.MAC

		// log.Debugf("   element %d: net_id=%d, net_type=%s", i, value.NetID, value.NetType)

		result = append(result, elem)
	}

	return result
}

/*
func parseComputeInterfacesToNetworks(ifaces []InterfaceRecord) []map[string]interface{} {
	// return value will be used to d.Set("network") item of dataSourceCompute schema
	length := len(ifaces)
	log.Debugf("parseComputeInterfacesToNetworks: called for %d ifaces", length)

	result := make([]map[string]interface{}, length, length)

	for i, value := range ifaces {
		elem := make(map[string]interface{})
		// Keys in this map should correspond to the Schema definition
		// as returned by networkSubresourceSchemaMake()
		elem["net_id"] = value.NetID
		elem["net_type"] = value.NetType
		elem["ip_address"] = value.IPAddress
		elem["mac"] = value.MAC

		// log.Debugf("   element %d: net_id=%d, net_type=%s", i, value.NetID, value.NetType)

		result[i] = elem
	}

	return result
}
*/

// NOTE: this function is retained for historical purposes and actually not used as of rc-1.10
func parseComputeInterfaces(ifaces []InterfaceRecord) []map[string]interface{} {
	// return value was designed to d.Set("interfaces",) item of dataSourceCompute schema
	// However, this item was excluded from the schema as it is not directly
	// managed through Terraform
	length := len(ifaces)
	log.Debugf("parseComputeInterfaces: called for %d ifaces", length)

	result := make([]map[string]interface{}, length, length)

	for i, value := range ifaces {
		// Keys in this map should correspond to the Schema definition
		// as returned by dataSourceInterfaceSchemaMake()
		elem := make(map[string]interface{})

		elem["net_id"] = value.NetID
		elem["net_type"] = value.NetType
		elem["ip_address"] = value.IPAddress
		elem["netmask"] = value.NetMask
		elem["mac"] = value.MAC
		elem["default_gw"] = value.DefaultGW
		elem["name"] = value.Name
		elem["connection_id"] = value.ConnID
		elem["connection_type"] = value.ConnType

		/* TODO: add code to parse QoS
		qos_schema := interfaceQosSubresourceSchemaMake()
		qos_schema.Set("egress_rate", value.QOS.ERate)
		qos_schema.Set("ingress_rate", value.QOS.InRate)
		qos_schema.Set("ingress_burst", value.QOS.InBurst)
		elem["qos"] = qos_schema
		*/

		result[i] = elem
	}

	return result
}

func flattenCompute(d *schema.ResourceData, compFacts string) error {
	// This function expects that compFacts string contains response from API compute/get,
	// i.e. detailed information about compute instance.
	//
	// NOTE: this function modifies ResourceData argument - as such it should never be called
	// from resourceComputeExists(...) method
	model := ComputeGetResp{}
	log.Debugf("flattenCompute: ready to unmarshal string %s", compFacts)
	err := json.Unmarshal([]byte(compFacts), &model)
	if err != nil {
		return err
	}

	log.Debugf("flattenCompute: ID %d, RG ID %d", model.ID, model.RgID)

	d.SetId(fmt.Sprintf("%d", model.ID))
	// d.Set("compute_id", model.ID) - we should NOT set compute_id in the schema here: if it was set - it is already set, if it wasn't - we shouldn't
	d.Set("name", model.Name)
	d.Set("rg_id", model.RgID)
	d.Set("rg_name", model.RgName)
	d.Set("account_id", model.AccountID)
	d.Set("account_name", model.AccountName)
	d.Set("arch", model.Arch)
	d.Set("cpu", model.Cpu)
	d.Set("ram", model.Ram)
	// d.Set("boot_disk_size", model.BootDiskSize) - bootdiskSize key in API compute/get is always zero, so we set boot_disk_size in another way
	d.Set("boot_disk_size", parseBootDiskSize(model.Disks))
	d.Set("boot_disk_id", parseBootDiskId(model.Disks)) // we may need boot disk ID in resize operations
	d.Set("image_id", model.ImageID)
	d.Set("description", model.Desc)
	d.Set("cloud_init", "applied") // NOTE: for existing compute we hard-code this value as an indicator for DiffSuppress fucntion
	// d.Set("status", model.Status)
	// d.Set("tech_status", model.TechStatus)

	if model.TechStatus == "STARTED" {
		d.Set("started", true)
	} else {
		d.Set("started", false)
	}

	if len(model.Disks) > 0 {
		log.Debugf("flattenCompute: calling parseComputeDisksToExtraDisks for %d disks", len(model.Disks))
		if err = d.Set("extra_disks", parseComputeDisksToExtraDisks(model.Disks)); err != nil {
			return err
		}
	}

	if len(model.Interfaces) > 0 {
		log.Debugf("flattenCompute: calling parseComputeInterfacesToNetworks for %d interfaces", len(model.Interfaces))
		if err = d.Set("network", parseComputeInterfacesToNetworks(model.Interfaces)); err != nil {
			return err
		}
	}

	if len(model.OsUsers) > 0 {
		log.Debugf("flattenCompute: calling parseOsUsers for %d logins", len(model.OsUsers))
		if err = d.Set("os_users", parseOsUsers(model.OsUsers)); err != nil {
			return err
		}
	}

	return nil
}

func dataSourceComputeRead(d *schema.ResourceData, m interface{}) error {
	compFacts, err := utilityComputeCheckPresence(d, m)
	if compFacts == "" {
		// if empty string is returned from utilityComputeCheckPresence then there is no
		// such Compute and err tells so - just return it to the calling party
		d.SetId("") // ensure ID is empty
		return err
	}

	return flattenCompute(d, compFacts)
}

func dataSourceCompute() *schema.Resource {
	return &schema.Resource{
		SchemaVersion: 1,

		Read: dataSourceComputeRead,

		Timeouts: &schema.ResourceTimeout{
			Read:    &Timeout30s,
			Default: &Timeout60s,
		},

		Schema: map[string]*schema.Schema{
			"name": {
				Type:        schema.TypeString,
				Optional:    true,
				Description: "Name of this compute instance. NOTE: this parameter is case sensitive.",
			},

			// TODO: consider removing compute_id from the schema, as it not practical to call this data provider if
			// corresponding compute ID is already known
			"compute_id": {
				Type:        schema.TypeInt,
				Optional:    true,
				Description: "ID of the compute instance. If ID is specified, name and resource group ID are ignored.",
			},

			"rg_id": {
				Type:        schema.TypeInt,
				Optional:    true,
				Description: "ID of the resource group where this compute instance is located.",
			},

			"rg_name": {
				Type:        schema.TypeString,
				Computed:    true,
				Description: "Name of the resource group where this compute instance is located.",
			},

			"account_id": {
				Type:        schema.TypeInt,
				Computed:    true,
				Description: "ID of the account this compute instance belongs to.",
			},

			"account_name": {
				Type:        schema.TypeString,
				Computed:    true,
				Description: "Name of the account this compute instance belongs to.",
			},

			"arch": {
				Type:        schema.TypeString,
				Computed:    true,
				Description: "Hardware architecture of this compute instance.",
			},

			"cpu": {
				Type:        schema.TypeInt,
				Computed:    true,
				Description: "Number of CPUs allocated for this compute instance.",
			},

			"ram": {
				Type:        schema.TypeInt,
				Computed:    true,
				Description: "Amount of RAM in MB allocated for this compute instance.",
			},

			"image_id": {
				Type:        schema.TypeInt,
				Computed:    true,
				Description: "ID of the OS image this compute instance is based on.",
			},

			"image_name": {
				Type:        schema.TypeString,
				Computed:    true,
				Description: "Name of the OS image this compute instance is based on.",
			},

			"boot_disk_size": {
				Type:        schema.TypeInt,
				Computed:    true,
				Description: "This compute instance boot disk size in GB.",
			},

			"boot_disk_id": {
				Type:        schema.TypeInt,
				Computed:    true,
				Description: "This compute instance boot disk ID.",
			},

			"extra_disks": {
				Type:     schema.TypeSet,
				Computed: true,
				MaxItems: MaxExtraDisksPerCompute,
				Elem: &schema.Schema{
					Type: schema.TypeInt,
				},
				Description: "IDs of the extra disk(s) attached to this compute.",
			},

			/*
				"disks": {
					Type:     schema.TypeList,
					Computed: true,
					Elem: &schema.Resource{
						Schema: dataSourceDiskSchemaMake(), // ID, type,  name, size, account ID, SEP ID, SEP type, pool, status, tech status, compute ID, image ID
					},
					Description: "Detailed specification for all disks attached to this compute instance (including bood disk).",
				},
			*/

			"network": {
				Type:     schema.TypeSet,
				Optional: true,
				MaxItems: MaxNetworksPerCompute,
				Elem: &schema.Resource{
					Schema: networkSubresourceSchemaMake(),
				},
				Description: "Network connection(s) for this compute.",
			},

			/*
				"interfaces": {
					Type:     schema.TypeList,
					Computed: true,
					Elem: &schema.Resource{
						Schema: interfaceSubresourceSchemaMake(),
					},
					Description: "Specification for the virtual NICs configured on this compute instance.",
				},
			*/

			"os_users": {
				Type:     schema.TypeList,
				Computed: true,
				Elem: &schema.Resource{
					Schema: osUsersSubresourceSchemaMake(),
				},
				Description: "Guest OS users provisioned on this compute instance.",
			},

			"description": {
				Type:        schema.TypeString,
				Computed:    true,
				Description: "User-defined text description of this compute instance.",
			},

			"cloud_init": {
				Type:        schema.TypeString,
				Computed:    true,
				Description: "Placeholder for cloud_init parameters.",
			},

			"started": {
				Type:        schema.TypeBool,
				Optional:    true,
				Default:     true,
				Description: "Is compute started.",
			},

			/*
				"status": {
					Type:        schema.TypeString,
					Computed:    true,
					Description: "Current model status of this compute instance.",
				},

				"tech_status": {
					Type:        schema.TypeString,
					Computed:    true,
					Description: "Current technical status of this compute instance.",
				},

				"internal_ip": {
					Type:          schema.TypeString,
					Computed:      true,
					Description:  "Internal IP address of this Compute.",
				},
			*/
		},
	}
}