From ce6d483135a3d7c5ca4a01a55d25180f8b5dc10b Mon Sep 17 00:00:00 2001
From: Jordan Bancino <jordan@bancino.net>
Date: Wed, 1 Mar 2023 19:03:42 +0000
Subject: [PATCH] Implement static login page.

---
 TODO.txt                 |  2 +-
 src/Db.c                 |  2 +-
 src/Static/StaticLogin.c | 88 +++++++++++++++++++++++++++++++++++++++-
 src/Uia.c                |  3 +-
 src/include/Db.h         |  2 +-
 5 files changed, 92 insertions(+), 5 deletions(-)

diff --git a/TODO.txt b/TODO.txt
index d5f2d97..5cc50a9 100644
--- a/TODO.txt
+++ b/TODO.txt
@@ -23,7 +23,7 @@ Milestone: v0.2.0
     [x] Logout
         [x] Delete refresh token if present
     [ ] Logout all
-    [~] Login fallback (static HTML page)
+    [x] Login fallback (static HTML page)
 [~] User Interactive
     [x] Passwords
     [x] Caller builds flows
diff --git a/src/Db.c b/src/Db.c
index aa393df..28f9a3f 100644
--- a/src/Db.c
+++ b/src/Db.c
@@ -795,7 +795,7 @@ DbExists(Db * db, size_t nArgs,...)
 }
 
 Array *
-DbList(Db *db, size_t nArgs, ...)
+DbList(Db * db, size_t nArgs,...)
 {
     Array *result;
 
diff --git a/src/Static/StaticLogin.c b/src/Static/StaticLogin.c
index 6383d9f..fe97829 100644
--- a/src/Static/StaticLogin.c
+++ b/src/Static/StaticLogin.c
@@ -39,15 +39,101 @@ StaticLogin(FILE * stream)
             "<br>"
             "<input type=\"submit\" value=\"Log In\">"
             "</form>"
+            "<style>"
+            "#error-msg {"
+            "  display: none;"
+            "  color: red;"
+            "  text-align: center;"
+            "  font-weight: bold;"
+            "  font-size: larger;"
+            "}"
+            "</style>"
+            "<p id=\"error-msg\"></p>"
             "</div>"
             );
 
     fprintf(stream,
             "<script>"
+            "function findGetParameter(parameterName) {"
+            "  var result = null;"
+            "  var tmp = [];"
+            "  var items = location.search.substr(1).split(\"&\");"
+            "  for (var index = 0; index < items.length; index++) {"
+            "    tmp = items[index].split(\"=\");"
+            "    if (tmp[0] === parameterName) result = decodeURIComponent(tmp[1]);"
+            "  }"
+            "  return result;"
+            "}"
+            "function setError(msg) {"
+            "  var err = document.getElementById('error-msg');"
+            "  if (msg) {"
+            "    err.style.display = 'block';"
+            "    err.innerHTML = msg;"
+            "  } else {"
+            "    err.style.display = 'none';"
+            "  }"
+            "}"
+            );
+
+    fprintf(stream,
+            "function buildRequest(user, pass) {"
+            "  var d = findGetParameter('device_id');"
+          "  var i = findGetParameter('initial_device_display_name');"
+            "  var r = findGetParameter('refresh_token') === 'true';"
+            "  var request = {};"
+            "  request['type'] = 'm.login.password';"
+            "  request['identifier'] = {"
+            "    type: 'm.id.user',"
+            "    user: user"
+            "  };"
+            "  request['password'] = pass;"
+            "  if (d) request['device_id'] = d;"
+            "  if (i) request['initial_device_display_name'] = i;"
+            "  if (r) request['refresh_token'] = r;"
+            "  return request;"
+            "}"
+            );
+
+    fprintf(stream,
+            "function processResponse(xhr) {"
+            "  if (xhr.readyState == 4) {"
+            "    var r = JSON.parse(xhr.responseText);"
+            "    if (!r.error) {"
+            "      if (window.onLogin) {"
+            "        window.onLogin(r);"
+            "      } else {"
+            "        setError('Client malfunction. Your client should have defined window.onLogin()');"
+            "      }"
+            "    } else {"
+            "      setError(r.errcode + ': ' + r.error);"
+            "    }"
+            "  }"
+            "}"
+            );
+
+    fprintf(stream,
+            "function sendRequest(request) {"
+            "  var xhr = new XMLHttpRequest();"
+            "  xhr.open('POST', '/_matrix/client/v3/login');"
+         "  xhr.setRequestHeader('Content-Type', 'application/json');"
+            "  xhr.onreadystatechange = () => processResponse(xhr);"
+            "  xhr.send(JSON.stringify(request));"
+            "}"
+            );
+
+    fprintf(stream,
             "window.addEventListener('load', () => {"
             "  document.getElementById('login-form').addEventListener('submit', (e) => {"
             "    e.preventDefault();"
-            "    /* TODO: Submit form here*/"
+            "    var user = document.getElementById('user').value;"
+            "    var pass = document.getElementById('password').value;"
+            "    if (!user || !pass) {"
+          "      setError('Please provide a username and password.');"
+            "      return;"
+            "    }"
+            "    setError(null);"
+            "    var request = buildRequest(user, pass);"
+            "    sendRequest(request);"
             "  });"
             "});"
             "</script>"
diff --git a/src/Uia.c b/src/Uia.c
index 2a6f64a..d52cb7e 100644
--- a/src/Uia.c
+++ b/src/Uia.c
@@ -411,7 +411,8 @@ UiaComplete(Array * flows, HttpServerContext * context, Db * db,
 
     ArrayAdd(completed, JsonValueString(authType));
 
-    ret = 1; /* TODO: Only return 1 if there are remaining stages */
+    ret = 1;                       /* TODO: Only return 1 if there are
+                                    * remaining stages */
 
 finish:
     ArrayFree(possibleNext);
diff --git a/src/include/Db.h b/src/include/Db.h
index 1096b74..6934263 100644
--- a/src/include/Db.h
+++ b/src/include/Db.h
@@ -58,7 +58,7 @@ extern int
  DbExists(Db *, size_t,...);
 
 extern Array *
- DbList(Db *, size_t, ...);
+ DbList(Db *, size_t,...);
 
 extern HashMap *
  DbJson(DbRef *);