// A class that translates the informations held in the graph object
// via its lists of components into an argo file, using the a list of
// link ID to build the dag

package workflow_builder

import (
	"fmt"
	. "oc-monitord/models"
	"os"
	"slices"
	"strings"
	"time"

	oclib "cloud.o-forge.io/core/oc-lib"
	"cloud.o-forge.io/core/oc-lib/models/resource_model"
	"cloud.o-forge.io/core/oc-lib/models/resources/workflow/graph"
	w "cloud.o-forge.io/core/oc-lib/models/workflow"
	"github.com/nwtgck/go-fakelish"
	"github.com/rs/zerolog"
	"gopkg.in/yaml.v3"
)

var logger zerolog.Logger

type ArgoBuilder struct {
	OriginWorkflow w.Workflow
	Workflow       Workflow
	Services       *Service
	Timeout        int
}

type Workflow struct {
	ApiVersion string `yaml:"apiVersion"`
	Kind       string `yaml:"kind"`
	Metadata   struct {
		Name string `yaml:"name"`
	} `yaml:"metadata"`
	Spec Spec `yaml:"spec,omitempty"`
}

type Spec struct {
	Entrypoint string                `yaml:"entrypoint"`
	Arguments  []Parameter           `yaml:"arguments,omitempty"`
	Volumes    []VolumeClaimTemplate `yaml:"volumeClaimTemplates,omitempty"`
	Templates  []Template            `yaml:"templates"`
	Timeout    int                   `yaml:"activeDeadlineSeconds,omitempty"`
}

func (b *ArgoBuilder) CreateDAG() (string, error) {

	// handle services by checking if there is only one processing with hostname and port

	b.createNginxVolumes()

	b.createTemplates()
	b.createDAGstep()
	b.createVolumes()

	if b.Timeout > 0 {
		b.Workflow.Spec.Timeout = b.Timeout
	}
	b.Workflow.Spec.Entrypoint = "dag"
	b.Workflow.ApiVersion = "argoproj.io/v1alpha1"
	b.Workflow.Kind = "Workflow"
	random_name := generateWfName()
	b.Workflow.Metadata.Name = "oc-monitor-" + random_name
	logger = oclib.GetLogger()
	yamlified, err := yaml.Marshal(b.Workflow)
	if err != nil {
		logger.Error().Msg("Could not transform object to yaml file")
		return "", err
	}

	// Give a unique name to each argo file with its timestamp DD:MM:YYYY_hhmmss
	current_timestamp := time.Now().Format("02_01_2006_150405")
	file_name := random_name + "_" + current_timestamp + ".yml"
	workflows_dir := "./argo_workflows/"
	err = os.WriteFile(workflows_dir+file_name, []byte(yamlified), 0660)
	if err != nil {
		logger.Error().Msg("Could not write the yaml file")
		return "", err
	}

	return file_name, nil
}

func (b *ArgoBuilder) createTemplates() {
	for _, comp := range b.getProcessings() {
		var command string
		var args string
		var env string

		comp_res := comp.Processing

		command = getStringValue(comp_res.AbstractResource, "command")
		args = getStringValue(comp_res.AbstractResource, "args")
		env = getStringValue(comp_res.AbstractResource, "env")

		image_name := strings.Split(command, " ")[0]   // TODO : decide where to store the image name, GUI or models.computing.Image
		temp_container := Container{Image: image_name} // TODO : decide where to store the image name, GUI or models.computing.Image
		temp_container.Command = getComputingCommands(command)
		temp_container.Args = getComputingArgs(args, command)
		// Only for dev purpose,
		input_names := getComputingEnvironmentName(strings.Split(env, " "))

		var inputs_container []Parameter
		for _, name := range input_names {
			inputs_container = append(inputs_container, Parameter{Name: name})
		}

		argo_name := getArgoName(comp_res.GetName(), comp.ID)
		new_temp := Template{Name: argo_name, Container: temp_container}
		new_temp.Inputs.Parameters = inputs_container
		new_temp.Container.VolumeMounts = append(new_temp.Container.VolumeMounts, VolumeMount{Name: "workdir", MountPath: "/mnt/vol"})            // TODO : replace this with a search of the storage / data source name
		new_temp.Container.VolumeMounts = append(new_temp.Container.VolumeMounts, VolumeMount{Name: "nginx-demo", MountPath: "/usr/share/nginx"}) // Used for processing services' demo with nginx

		if b.isService(comp.ID) {
			serv := b.CreateService(comp)
			b.createService(serv, argo_name, comp.ID)
			new_temp.Metadata.Labels = make(map[string]string)
			new_temp.Metadata.Labels["app"] = "oc-service" // Construct the template for the k8s service and add a link in graph between k8s service and processing
			// if err != nil {
			// 	// TODO
			// }
		}

		b.Workflow.Spec.Templates = append(b.Workflow.Spec.Templates, new_temp)
	}

	if b.Services != nil {
		b.addServiceToArgo()
	}

}

func (b *ArgoBuilder) createDAGstep() {
	new_dag := Dag{}
	for _, comp := range b.getProcessings() {
		comp_res := comp.Processing
		env := getStringValue(comp_res.AbstractResource, "env")
		unique_name := getArgoName(comp_res.GetName(), comp.ID)
		step := Task{Name: unique_name, Template: unique_name}
		comp_envs := getComputingEnvironment(strings.Split(env, " "))

		for name, value := range comp_envs {
			step.Arguments.Parameters = append(step.Arguments.Parameters, Parameter{Name: name, Value: value})
		}

		// retrieves the name (computing.name-computing.ID)
		step.Dependencies = b.getDependency(comp.ID) // Error : we use the component ID instead of the GraphItem ID -> store objects
		new_dag.Tasks = append(new_dag.Tasks, step)
	}

	if b.Services != nil {
		new_dag.Tasks = append(new_dag.Tasks, Task{Name: "workflow-service-pod", Template: "workflow-service-pod"})
	}

	b.Workflow.Spec.Templates = append(b.Workflow.Spec.Templates, Template{Name: "dag", Dag: new_dag})

}

func (b *ArgoBuilder) createVolumes() {
	// For testing purposes we only declare one volume, mounted in each computing
	new_volume := VolumeClaimTemplate{}
	new_volume.Metadata.Name = "workdir"
	new_volume.Spec.AccessModes = []string{"ReadWriteOnce"}
	new_volume.Spec.Resources.Requests.Storage = "1Gi"
	b.Workflow.Spec.Volumes = append(b.Workflow.Spec.Volumes, new_volume)
}

// For demo purposes, until we implement the use of storage ressources
func (b *ArgoBuilder) createNginxVolumes() {
	new_volume := VolumeClaimTemplate{}
	new_volume.Metadata.Name = "nginx-demo"
	new_volume.Spec.AccessModes = []string{"ReadWriteOnce"}
	new_volume.Spec.Resources.Requests.Storage = "1Gi"

	b.Workflow.Spec.Volumes = append(b.Workflow.Spec.Volumes, new_volume)
}

func (b *ArgoBuilder) getDependency(current_computing_id string) (dependencies []string) {
	for _, link := range b.OriginWorkflow.Graph.Links {
		if b.OriginWorkflow.Graph.Items[link.Source.ID].Processing == nil {
			continue
		}
		source := b.OriginWorkflow.Graph.Items[link.Source.ID].Processing
		fmt.Println("source", source, current_computing_id, link.Destination.ID)
		if current_computing_id == link.Destination.ID && source != nil {
			dependency_name := getArgoName(source.GetName(), link.Source.ID)
			dependencies = append(dependencies, dependency_name)
		}
	}
	return

}

func getComputingCommands(user_input string) []string {
	user_input = removeImageName(user_input)
	if len(user_input) == 0 {
		return []string{}
	}
	return strings.Split(user_input, " ")
}

func getComputingArgs(user_input string, command string) (list_args []string) {
	if len(user_input) == 0 {
		return
	}

	args := strings.Split(user_input, " ")

	// quickfix that might need improvement
	if strings.Contains(command, "sh -c") {
		list_args = append(list_args, strings.Join(args, " "))
		return
	}

	list_args = append(list_args, args...)
	return
}

// Currently implements code to overcome problems in data structure
func getComputingEnvironment(user_input []string) (map_env map[string]string) {
	logger := oclib.GetLogger()
	is_empty := len(user_input) == 0
	is_empty_string := len(user_input) == 1 && user_input[0] == ""

	if is_empty || is_empty_string {
		return
	}

	if len(user_input) == 1 {
		user_input = strings.Split(user_input[0], ",")
	}

	map_env = make(map[string]string, 0)

	for _, str := range user_input {
		new_pair := strings.Split(str, "=")

		if len(new_pair) != 2 {
			logger.Error().Msg("Error extracting the environment variable from " + str)
			panic(0)
		}

		map_env[new_pair[0]] = new_pair[1]
	}

	return
}

func getComputingEnvironmentName(user_input []string) (list_names []string) {
	env_map := getComputingEnvironment(user_input)
	for name := range env_map {
		list_names = append(list_names, name)
	}

	return
}

func generateWfName() (Name string) {
	Name = fakelish.GenerateFakeWord(5, 8) + "-" + fakelish.GenerateFakeWord(5, 8)
	return
}

func getArgoName(raw_name string, component_id string) (formatedName string) {
	formatedName = strings.ReplaceAll(raw_name, " ", "-")
	formatedName += "-" + component_id
	formatedName = strings.ToLower(formatedName)
	return
}

func removeImageName(user_input string) string {
	// First command is the name of the container for now
	if len(strings.Split(user_input, " ")) == 1 {
		return ""
	}

	slice_input := strings.Split(user_input, " ")
	new_slice := slice_input[1:]
	user_input = strings.Join(new_slice, " ")

	return user_input
}

// Return the graphItem containing a Processing resource, so that we have access to the ID of the graphItem in order to identify it in the links
func (b *ArgoBuilder) getProcessings() (list_computings []graph.GraphItem) {
	for _, item := range b.OriginWorkflow.Graph.Items {
		if item.Processing != nil {
			list_computings = append(list_computings, item)
		}
	}
	return
}

// Pass a GraphItem's UUID and not the ID
func (b *ArgoBuilder) IsProcessing(component_uuid string) bool {
	return slices.Contains(b.OriginWorkflow.Processings, component_uuid)
}

func getStringValue(comp resource_model.AbstractResource, key string) string {
	if res := comp.GetModelValue(key); res != nil {
		return res.(string)
	}
	return ""
}

func (b *ArgoBuilder) isService(id string) bool {

	comp := b.OriginWorkflow.Graph.Items[id]

	if comp.Processing == nil {
		return false
	}

	_, is_exposed := comp.Processing.ResourceModel.Model["expose"]
	return is_exposed
}

func (b *ArgoBuilder) addLabel(name string, id string) {
	argo_name := getArgoName(name, id)
	for _, template := range b.Workflow.Spec.Templates {
		if template.Name == argo_name {
			template.Metadata.Labels["app"] = "service-workflow"
			return
		}
	}
}