Add install command

pkg/wpm/package.go

@@ -8,6 +8,13 @@ type Dist struct {
 	UnpackedSize int    `json:"unpackedSize"`
 }
 
+// PackageConfig struct to define the package configuration
+type PackageConfig struct {
+	BinDir         string `json:"bin-dir,omitempty"`
+	ContentDir     string `json:"content-dir,omitempty"`
+	PlatformStrict bool   `json:"platform-strict,omitempty"` // If set to true, wpm will refuse to install the package if the platform requirements are not met.
+}
+
 // Config struct to define the wpm.json schema
 type Config struct {
 	Name            string            `json:"name" validate:"required,min=3,max=164,package_name_regex"`
@@ -23,6 +30,7 @@ type Config struct {
 	Dependencies    map[string]string `json:"dependencies,omitempty" validate:"omitempty,package_dependencies"`
 	DevDependencies map[string]string `json:"devDependencies,omitempty" validate:"omitempty,package_dependencies"`
 	Scripts         map[string]string `json:"scripts,omitempty"`
+	Config          PackageConfig     `json:"config,omitempty" validate:"omitempty"`
 }
 
 // Meta struct to define the package metadata

pkg/wpm/sumfile/sum.go

@@ -0,0 +1,110 @@
+package sumfile
+
+import (
+	"bufio"
+	"crypto/sha256"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"sync"
+
+	"github.com/pkg/errors"
+)
+
+const SumFile = "wpm.sum"
+
+// Sum represents a single line in the wpm.sum file.
+type Sum struct {
+	Name    string
+	Version string
+	Hash    string
+}
+
+// SumDB holds the parsed content of a wpm.sum file.
+type SumDB struct {
+	mu   sync.RWMutex
+	file string
+	sums map[string]map[string]string // map[name]map[version]hash
+}
+
+// NewSumDB creates a new SumDB and loads the sum file from the given path.
+func NewSumDB(path string) (*SumDB, error) {
+	db := &SumDB{
+		file: filepath.Join(path, SumFile),
+		sums: make(map[string]map[string]string),
+	}
+
+	f, err := os.Open(db.file)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return db, nil // File doesn't exist, which is fine.
+		}
+		return nil, errors.Wrapf(err, "failed to open %s", db.file)
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		parts := strings.Fields(scanner.Text())
+		if len(parts) != 3 {
+			continue // Ignore malformed lines
+		}
+		if db.sums[parts[0]] == nil {
+			db.sums[parts[0]] = make(map[string]string)
+		}
+		db.sums[parts[0]][parts[1]] = parts[2]
+	}
+
+	return db, scanner.Err()
+}
+
+// Add adds a new sum to the database.
+func (db *SumDB) Add(name, version, hash string) {
+	db.mu.Lock()
+	defer db.mu.Unlock()
+
+	if db.sums[name] == nil {
+		db.sums[name] = make(map[string]string)
+	}
+	db.sums[name][version] = hash
+}
+
+// Get returns the hash for a given package and version.
+func (db *SumDB) Get(name, version string) (string, bool) {
+	db.mu.RLock()
+	defer db.mu.RUnlock()
+
+	if v, ok := db.sums[name]; ok {
+		hash, ok := v[version]
+		return hash, ok
+	}
+	return "", false
+}
+
+// Save writes the current state of the database back to the wpm.sum file.
+func (db *SumDB) Save() error {
+	db.mu.RLock()
+	defer db.mu.RUnlock()
+
+	var lines []string
+	for name, versions := range db.sums {
+		for version, hash := range versions {
+			lines = append(lines, fmt.Sprintf("%s %s %s", name, version, hash))
+		}
+	}
+	sort.Strings(lines) // For deterministic output
+
+	return os.WriteFile(db.file, []byte(strings.Join(lines, "\n")+"\n"), 0644)
+}
+
+// CalculateHash computes the SHA256 hash of a reader's content and returns it in "sha256:..." format.
+func CalculateHash(r io.Reader) (string, error) {
+	hasher := sha256.New()
+	if _, err := io.Copy(hasher, r); err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("sha256:%x", hasher.Sum(nil)), nil
+}