Add Debian package registry (#22854)

Co-authored-by: @awkwardbunny

This PR adds a Debian package registry. You can follow [this
tutorial](https://www.baeldung.com/linux/create-debian-package) to build
a *.deb package for testing. Source packages are not supported at the
moment and I did not find documentation of the architecture "all" and
how these packages should be treated.

---------

Co-authored-by: Brian Hong <brian@hongs.me>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

models/packages/debian/search.go

@@ -0,0 +1,131 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package debian
+
+import (
+	"context"
+	"strconv"
+
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/models/packages"
+	debian_module "code.gitea.io/gitea/modules/packages/debian"
+
+	"xorm.io/builder"
+)
+
+type PackageSearchOptions struct {
+	OwnerID      int64
+	Distribution string
+	Component    string
+	Architecture string
+}
+
+// SearchLatestPackages gets the latest packages matching the search options
+func SearchLatestPackages(ctx context.Context, opts *PackageSearchOptions) ([]*packages.PackageFileDescriptor, error) {
+	var cond builder.Cond = builder.Eq{
+		"package_file.is_lead":        true,
+		"package.type":                packages.TypeDebian,
+		"package.owner_id":            opts.OwnerID,
+		"package.is_internal":         false,
+		"package_version.is_internal": false,
+	}
+
+	props := make(map[string]string)
+	if opts.Distribution != "" {
+		props[debian_module.PropertyDistribution] = opts.Distribution
+	}
+	if opts.Component != "" {
+		props[debian_module.PropertyComponent] = opts.Component
+	}
+	if opts.Architecture != "" {
+		props[debian_module.PropertyArchitecture] = opts.Architecture
+	}
+
+	if len(props) > 0 {
+		var propsCond builder.Cond = builder.Eq{
+			"package_property.ref_type": packages.PropertyTypeFile,
+		}
+		propsCond = propsCond.And(builder.Expr("package_property.ref_id = package_file.id"))
+
+		propsCondBlock := builder.NewCond()
+		for name, value := range props {
+			propsCondBlock = propsCondBlock.Or(builder.Eq{
+				"package_property.name":  name,
+				"package_property.value": value,
+			})
+		}
+		propsCond = propsCond.And(propsCondBlock)
+
+		cond = cond.And(builder.Eq{
+			strconv.Itoa(len(props)): builder.Select("COUNT(*)").Where(propsCond).From("package_property"),
+		})
+	}
+
+	cond = cond.
+		And(builder.Expr("pv2.id IS NULL"))
+
+	joinCond := builder.
+		Expr("package_version.package_id = pv2.package_id AND (package_version.created_unix < pv2.created_unix OR (package_version.created_unix = pv2.created_unix AND package_version.id < pv2.id))").
+		And(builder.Eq{"pv2.is_internal": false})
+
+	pfs := make([]*packages.PackageFile, 0, 10)
+	err := db.GetEngine(ctx).
+		Table("package_file").
+		Select("package_file.*").
+		Join("INNER", "package_version", "package_version.id = package_file.version_id").
+		Join("LEFT", "package_version pv2", joinCond).
+		Join("INNER", "package", "package.id = package_version.package_id").
+		Where(cond).
+		Desc("package_version.created_unix").
+		Find(&pfs)
+	if err != nil {
+		return nil, err
+	}
+
+	return packages.GetPackageFileDescriptors(ctx, pfs)
+}
+
+// GetDistributions gets all available distributions
+func GetDistributions(ctx context.Context, ownerID int64) ([]string, error) {
+	return getDistinctPropertyValues(ctx, ownerID, "", debian_module.PropertyDistribution)
+}
+
+// GetComponents gets all available components for the given distribution
+func GetComponents(ctx context.Context, ownerID int64, distribution string) ([]string, error) {
+	return getDistinctPropertyValues(ctx, ownerID, distribution, debian_module.PropertyComponent)
+}
+
+// GetArchitectures gets all available architectures for the given distribution
+func GetArchitectures(ctx context.Context, ownerID int64, distribution string) ([]string, error) {
+	return getDistinctPropertyValues(ctx, ownerID, distribution, debian_module.PropertyArchitecture)
+}
+
+func getDistinctPropertyValues(ctx context.Context, ownerID int64, distribution, propName string) ([]string, error) {
+	var cond builder.Cond = builder.Eq{
+		"package_property.ref_type": packages.PropertyTypeFile,
+		"package_property.name":     propName,
+		"package.type":              packages.TypeDebian,
+		"package.owner_id":          ownerID,
+	}
+	if distribution != "" {
+		innerCond := builder.
+			Expr("pp.ref_id = package_property.ref_id").
+			And(builder.Eq{
+				"pp.ref_type": packages.PropertyTypeFile,
+				"pp.name":     debian_module.PropertyDistribution,
+				"pp.value":    distribution,
+			})
+		cond = cond.And(builder.Exists(builder.Select("pp.ref_id").From("package_property pp").Where(innerCond)))
+	}
+
+	values := make([]string, 0, 5)
+	return values, db.GetEngine(ctx).
+		Table("package_property").
+		Distinct("package_property.value").
+		Join("INNER", "package_file", "package_file.id = package_property.ref_id").
+		Join("INNER", "package_version", "package_version.id = package_file.version_id").
+		Join("INNER", "package", "package.id = package_version.package_id").
+		Where(cond).
+		Find(&values)
+}