package db

import (
	"testing"
	"testing/quick"

	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
)

func OpenTemporaryDB() (*Database, error) {
	db, err := gorm.Open(sqlite.Open(":memory:"), &gormConfig)
	if err != nil {
		return nil, err
	}
	migrate := Gormigrate(db)
	if err := migrate.Migrate(); err != nil {
		return nil, err
	}
	return db, nil
}

func TestValidatePasteKey(t *testing.T) {
	tests := []struct {
		key     string
		wantErr bool
		errKind error
	}{
		{"xd42__", false, nil},
		{"xd42_*", true, ErrKeyInvalidChar},
		{"xd42_/", true, ErrKeyInvalidChar},
		{"xd42_=", true, ErrKeyInvalidChar},
		{"xd42_", true, ErrKeyInvalidLength},
		{"xd42", true, ErrKeyInvalidLength},
		{"xd4", true, ErrKeyInvalidLength},
		{"xd", true, ErrKeyInvalidLength},
		{"x", true, ErrKeyInvalidLength},
		{"", true, ErrKeyInvalidLength},

		{"KoJ5", false, nil},

		{"__dGSJIIbBpr-SD0", false, nil},
		{"__dGSJIIbBpr-SD", true, ErrKeyInvalidLength},
	}
	for _, tt := range tests {
		t.Run(tt.key, func(t *testing.T) {
			err := ValidatePasteKey(tt.key)
			if (err != nil) != tt.wantErr {
				t.Errorf("ValidatePasteKey() got error = %v, want error %v", err != nil, tt.wantErr)
			}
			if (err != nil) && err != tt.errKind {
				t.Errorf("ValidatePasteKey() error = %v, want errKind %v", err, tt.errKind)
			}
		})
	}
}

func TestGeneratedKeysAreValid(t *testing.T) {
	db, err := OpenTemporaryDB()
	if err != nil {
		t.Error(err)
	}
	var minimumEntropy int
	checkGeneratedKeyValid := func() bool {
		key, err := GeneratePasteKey(db, minimumEntropy)
		if err != nil {
			return false
		}
		return ValidatePasteKey(key) == nil
	}

	for minimumEntropy = 0; minimumEntropy <= 80; minimumEntropy++ {
		if err = quick.Check(checkGeneratedKeyValid, nil); err != nil {
			t.Error(err)
		}
	}
}

func TestTruncatedKeysAreInvalid(t *testing.T) {
	db, err := OpenTemporaryDB()
	if err != nil {
		t.Error(err)
	}
	var minimumEntropy int
	checkTruncatedKeysInvalid := func(truncRand uint) bool {
		key, err := GeneratePasteKey(db, minimumEntropy)
		if err != nil {
			return false
		}
		trunc := int(truncRand % uint(len(key)-1))
		key = key[:trunc]
		return ValidatePasteKey(key) == ErrKeyInvalidLength
	}

	for minimumEntropy = 0; minimumEntropy <= 80; minimumEntropy++ {
		if err = quick.Check(checkTruncatedKeysInvalid, nil); err != nil {
			t.Error(err)
		}
	}
}