Fix various bugs for "install" page (#23194)

## TLDR

* Fix the broken page / broken image problem when click "Install"
* Close #20089
* Fix the Password Hash Algorithm display problem for #22942
* Close #23183
* Close #23184

## Details

### The broken page / broken image problem when click "Install"
(Redirect failed after install gitea #23184)

Before: when click "install", all new requests will fail, because the
server has been restarted. Users just see a broken page with broken
images, sometimes the server is not ready but the user would have been
redirect to "/user/login" page, then the users see a new broken page
(connection refused or something wrong ...)

After: only check InstallLock=true for necessary handlers, and sleep for
a while before restarting the server, then the browser has enough time
to load the "post-install" page. And there is a script to check whether
"/user/login" is ready, the user will only be redirected to the login
page when the server is ready.

### During new instance setup make 'Gitea Base URL' filled from
window.location.origin #20089

If the "app_url" input contains `localhost` (the default value from
config), use current window's location href as the `app_url` (aka
ROOT_URL)

### Fix the Password Hash Algorithm display problem for "Provide the
ability to set password hash algorithm parameters #22942"

Before: the UI shows `pbkdf2$50000$50`

<details>

![image](https://user-images.githubusercontent.com/2114189/221917143-e1e54798-1698-4fee-a18d-00c48081fc39.png)

</details>

After: the UI shows `pbkdf2`

<details>

![image](https://user-images.githubusercontent.com/2114189/221916999-97a15be8-2ebb-4a01-bf93-dac18e354fcc.png)

</details>

### GET data: net::ERR_INVALID_URL #23183

Cause by empty `data:` in `<link rel="manifest"
href="data:{{.ManifestData}}">`

---------

Co-authored-by: Jason Song <i@wolfogre.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

1 files changed, 22 insertions, 7 deletions

diff --git a/modules/auth/password/hash/setting.go b/modules/auth/password/hash/setting.go
index 701697430..f0715f31e 100644
--- a/modules/auth/password/hash/setting.go
+++ b/modules/auth/password/hash/setting.go
@@ -41,9 +41,8 @@ var RecommendedHashAlgorithms = []string{
 	"pbkdf2_hi",
 }
 
-// SetDefaultPasswordHashAlgorithm will take a provided algorithmName and dealias it to
-// a complete algorithm specification.
-func SetDefaultPasswordHashAlgorithm(algorithmName string) (string, *PasswordHashAlgorithm) {
+// hashAlgorithmToSpec converts an algorithm name or a specification to a full algorithm specification
+func hashAlgorithmToSpec(algorithmName string) string {
 	if algorithmName == "" {
 		algorithmName = DefaultHashAlgorithmName
 	}
@@ -52,10 +51,26 @@ func SetDefaultPasswordHashAlgorithm(algorithmName string) (string, *PasswordHas
 		algorithmName = alias
 		alias, has = aliasAlgorithmNames[algorithmName]
 	}
+	return algorithmName
+}
 
-	// algorithmName should now be a full algorithm specification
-	// e.g. pbkdf2$50000$50 rather than pbdkf2
-	DefaultHashAlgorithm = Parse(algorithmName)
+// SetDefaultPasswordHashAlgorithm will take a provided algorithmName and de-alias it to
+// a complete algorithm specification.
+func SetDefaultPasswordHashAlgorithm(algorithmName string) (string, *PasswordHashAlgorithm) {
+	algoSpec := hashAlgorithmToSpec(algorithmName)
+	// now we get a full specification, e.g. pbkdf2$50000$50 rather than pbdkf2
+	DefaultHashAlgorithm = Parse(algoSpec)
+	return algoSpec, DefaultHashAlgorithm
+}
 
-	return algorithmName, DefaultHashAlgorithm
+// ConfigHashAlgorithm will try to find a "recommended algorithm name" defined by RecommendedHashAlgorithms for config
+// This function is not fast and is only used for the installation page
+func ConfigHashAlgorithm(algorithm string) string {
+	algorithm = hashAlgorithmToSpec(algorithm)
+	for _, recommAlgo := range RecommendedHashAlgorithms {
+		if algorithm == hashAlgorithmToSpec(recommAlgo) {
+			return recommAlgo
+		}
+	}
+	return algorithm
 }