package database

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"strings"

	"github.com/arangodb/go-driver"
	"github.com/docker/docker/client"
	"github.com/xeipuuv/gojsonschema"

	"github.com/SecurityBrewery/catalyst/caql"
	"github.com/SecurityBrewery/catalyst/database/busdb"
	"github.com/SecurityBrewery/catalyst/generated/models"
)

func toJob(doc *models.JobForm) *models.Job {
	return &models.Job{
		Automation: doc.Automation,
		Payload:    doc.Payload,
		Origin:     doc.Origin,
		Running:    true,
		Status:     "created",
	}
}

func (db *Database) toJobResponse(ctx context.Context, key string, doc *models.Job, update bool) (*models.JobResponse, error) {
	cli, err := client.NewClientWithOpts(client.FromEnv)
	if err != nil {
		return nil, err
	}
	defer cli.Close()

	status := doc.Status

	if doc.Running {
		inspect, err := cli.ContainerInspect(ctx, key)
		if err != nil || inspect.State == nil {
			doc.Running = false
			if update {
				db.JobUpdate(ctx, key, doc)
			}
		} else if doc.Status != inspect.State.Status {
			status = inspect.State.Status
			doc.Status = inspect.State.Status
			if update {
				db.JobUpdate(ctx, key, doc)
			}
		}
	}

	return &models.JobResponse{
		Automation: doc.Automation,
		ID:         key,
		Log:        doc.Log,
		Payload:    doc.Payload,
		Origin:     doc.Origin,
		Output:     doc.Output,
		Status:     status,
		Container:  doc.Container,
	}, nil
}

func (db *Database) JobCreate(ctx context.Context, id string, job *models.JobForm) (*models.JobResponse, error) {
	if job == nil {
		return nil, errors.New("requires job")
	}

	var doc models.Job
	newctx := driver.WithReturnNew(ctx, &doc)

	/* Start validation */
	j := toJob(job)
	b, _ := json.Marshal(j)

	r, err := models.JobSchema.Validate(gojsonschema.NewBytesLoader(b))
	if err != nil {
		return nil, err
	}

	if !r.Valid() {
		var errs []string
		for _, e := range r.Errors() {
			errs = append(errs, e.String())
		}
		return nil, errors.New(strings.Join(errs, ", "))
	}
	/* End validation */

	meta, err := db.jobCollection.CreateDocument(ctx, newctx, id, j)
	if err != nil {
		return nil, err
	}

	return db.toJobResponse(ctx, meta.Key, &doc, true)
}

func (db *Database) JobGet(ctx context.Context, id string) (*models.JobResponse, error) {
	var doc models.Job
	meta, err := db.jobCollection.ReadDocument(ctx, id, &doc)
	if err != nil {
		return nil, err
	}

	return db.toJobResponse(ctx, meta.Key, &doc, true)
}

func (db *Database) JobUpdate(ctx context.Context, id string, job *models.Job) (*models.JobResponse, error) {
	var doc models.Job
	ctx = driver.WithReturnNew(ctx, &doc)

	/* Start validation */
	b, _ := json.Marshal(job)

	r, err := models.JobSchema.Validate(gojsonschema.NewBytesLoader(b))
	if err != nil {
		return nil, err
	}

	if !r.Valid() {
		var errs []string
		for _, e := range r.Errors() {
			errs = append(errs, e.String())
		}
		return nil, errors.New(strings.Join(errs, ", "))
	}
	/* End validation */

	meta, err := db.jobCollection.ReplaceDocument(ctx, id, job)
	if err != nil {
		return nil, err
	}

	return db.toJobResponse(ctx, meta.Key, &doc, true)
}

func (db *Database) JobLogAppend(ctx context.Context, id string, logLine string) error {
	query := `LET d = DOCUMENT(@@collection, @ID)
	UPDATE d WITH { "log": CONCAT(NOT_NULL(d.log, ""), @logline) } IN @@collection`
	cur, _, err := db.Query(ctx, query, map[string]interface{}{
		"@collection": JobCollectionName,
		"ID":          id,
		"logline":     logLine,
	}, &busdb.Operation{
		OperationType: busdb.Update,
		Ids: []driver.DocumentID{
			driver.DocumentID(fmt.Sprintf("%s/%s", JobCollectionName, id)),
		},
		Msg: fmt.Sprintf("Append logline"),
	})
	if err != nil {
		return err
	}
	defer cur.Close()

	return nil
}

func (db *Database) JobComplete(ctx context.Context, id string, out interface{}) error {
	query := `LET d = DOCUMENT(@@collection, @ID)
	UPDATE d WITH { "output": @out, "status": "completed", "running": false } IN @@collection`
	cur, _, err := db.Query(ctx, query, map[string]interface{}{
		"@collection": JobCollectionName,
		"ID":          id,
		"out":         out,
	}, &busdb.Operation{
		OperationType: busdb.Update,
		Ids: []driver.DocumentID{
			driver.DocumentID(fmt.Sprintf("%s/%s", JobCollectionName, id)),
		},
		Msg: fmt.Sprintf("Set output"),
	})
	if err != nil {
		return err
	}
	defer cur.Close()

	return nil
}

func (db *Database) JobDelete(ctx context.Context, id string) error {
	_, err := db.jobCollection.RemoveDocument(ctx, id)
	return err
}

func (db *Database) JobList(ctx context.Context) ([]*models.JobResponse, error) {
	query := "FOR d IN @@collection RETURN d"
	cursor, _, err := db.Query(ctx, query, map[string]interface{}{"@collection": JobCollectionName}, busdb.ReadOperation)
	if err != nil {
		return nil, err
	}
	defer cursor.Close()
	var docs []*models.JobResponse
	for {
		var doc models.Job
		meta, err := cursor.ReadDocument(ctx, &doc)
		if driver.IsNoMoreDocuments(err) {
			break
		} else if err != nil {
			return nil, err
		}

		job, err := db.toJobResponse(ctx, meta.Key, &doc, false)
		if err != nil {
			return nil, err
		}

		docs = append(docs, job)
	}

	return docs, err
}

func publishJobMapping(id, automation string, contextStructs *models.Context, origin *models.Origin, payloadMapping map[string]string, db *Database) error {
	msg, err := generatePayload(payloadMapping, contextStructs)
	if err != nil {
		return fmt.Errorf("message generation failed: %w", err)
	}

	return publishJob(id, automation, contextStructs, origin, msg, db)
}

func publishJob(id, automation string, contextStructs *models.Context, origin *models.Origin, payload map[string]interface{}, db *Database) error {
	return db.bus.PublishJob(id, automation, payload, contextStructs, origin)
}

func generatePayload(msgMapping map[string]string, contextStructs *models.Context) (map[string]interface{}, error) {
	contextJson, err := json.Marshal(contextStructs)
	if err != nil {
		return nil, err
	}

	automationContext := map[string]interface{}{}
	err = json.Unmarshal(contextJson, &automationContext)
	if err != nil {
		return nil, err
	}

	parser := caql.Parser{}
	msg := map[string]interface{}{}
	for arg, expr := range msgMapping {
		tree, err := parser.Parse(expr)
		if err != nil {
			return nil, err
		}

		v, err := tree.Eval(automationContext)
		if err != nil {
			return nil, err
		}
		msg[arg] = v
	}
	return msg, nil
}