// Copyright 2023 wanderer <a_mirre at utb dot cz>
// SPDX-License-Identifier: AGPL-3.0-only

package localbreach

import (
	"bytes"
	"context"
	"io"
	"os"

	"git.dotya.ml/mirre-mt/pcmt/ent"
	"git.dotya.ml/mirre-mt/pcmt/ent/schema"
	"git.dotya.ml/mirre-mt/pcmt/slogging"
	"golang.org/x/exp/slog"
	"gopkg.in/yaml.v3"
)

type CtxKey struct{}

// Load loads local breach data and returns a pointer to the slice of the
// structs, of which each holds one YAML document on successful import, error
// otherwise.
func Load(path string) (*[]schema.ImportSchema, error) {
	b, err := os.ReadFile(path)
	if err != nil {
		return nil, err
	}

	lb, err := loadLocalBreach(b)
	if err != nil {
		return nil, err
	}

	return lb, nil
}

func loadLocalBreach(b []byte) (*[]schema.ImportSchema, error) {
	r := bytes.NewReader(b)
	decoder := yaml.NewDecoder(r)
	lb := make([]schema.ImportSchema, 0)

	var is schema.ImportSchema

	for {
		if err := decoder.Decode(&is); err != nil {
			if err != io.EOF {
				return nil, err
			}

			break // get out when there are no more documents to read.
		}

		lb = append(lb, is)
	}

	return &lb, nil
}

// ImportLocalBreach imports data that from YAML files into the database. The
// data must adhere to the ImportSchema.
func ImportLocalBreach(ctx context.Context, db *ent.Client, b *[]schema.ImportSchema) ([]*ent.LocalBreach, error) {
	slogger := ctx.Value(CtxKey{}).(*slogging.Slogger)
	log := *slogger

	log.Logger = log.With(
		slog.Group("pcmt extra", slog.String("module", "modules/localbreach")),
	)

	var err error

	var lbs []*ent.LocalBreach

	// go through the documents, abort saving to DB on err of one.
	for _, breach := range *b {
		lb, err := db.LocalBreach.
			Create().
			SetName(breach.Name).
			SetNillableDescription(&breach.Description).
			SetIsVerified(breach.IsVerified).
			SetContainsEmails(breach.ContainsEmails).
			SetContainsUsernames(breach.ContainsUsernames).
			SetContainsPasswords(breach.ContainsPasswords).
			SetContainsHashes(breach.ContainsHashes).
			SetNillableHashSalted(&breach.HashSalted).
			SetNillableHashPeppered(&breach.HashPeppered).
			SetNillableHashType(&breach.HashType).
			SetNillableDate(&breach.Date).
			SetData(&breach.Data).
			Save(ctx)
		if err != nil {
			break
		}

		lbs = append(lbs, lb)
	}

	switch {
	case lbs == nil && err != nil:
		return nil, err

	case ent.IsConstraintError(err):
		return nil, err

	case err == nil && lbs != nil:
		return lbs, nil
	}

	return nil, err
}