const DB_SCHEMA = 1;

 const ID_SUFFIX = "@slipperymonkey.fractalbrew.com";

 var TAGMATCH = /^.*@(\S+)\s*(.*)/

 var ScriptDatabase = {

   db: null,

   startup: function() {

     var dbfile = Services.dirsvc.get("ProfD", Ci.nsIFile);

     dbfile.append("slippery.sqlite");

     this.db = Services.storage.openUnsharedDatabase(dbfile);

     if (this.db.schemaVersion < DB_SCHEMA)

       this.initDatabase();

   },

   initDatabase: function() {

     this.db.createTable("script",

                         "id INTEGER PRIMARY KEY AUTOINCREMENT," +

                         "name TEXT," +

                         "version TEXT," +

                         "author TEXT," +

                         "description TEXT," +

                         "uri TEXT," +

                         "enabled INTEGER," +

                         "script TEXT");

     this.db.createTable("include",

                         "script_id INTEGER," +

                         "address TEXT");

     this.db.executeSimpleSQL("CREATE TRIGGER delete_script AFTER DELETE ON script BEGIN " +

         "DELETE FROM include WHERE script_id=old.id; " +

       "END");

     this.db.schemaVersion = DB_SCHEMA;

   },

   getScript: function(aId) {

     if (aId.substring(aId.length - ID_SUFFIX.length) != ID_SUFFIX)

       return null;

     var stmt = this.db.createStatement("SELECT id, name, version, author, description, uri, enabled, script FROM script WHERE id=:id");

     stmt.params.id = aId.substring(0, aId.length - ID_SUFFIX.length);

     if (stmt.executeStep())

       return new Script(stmt.row);

     return null;

   },

   getAllScripts: function() {

     var scripts = [];

     var stmt = this.db.createStatement("SELECT id, name, version, author, description, uri, enabled, script FROM script");

     while (stmt.executeStep())

       scripts.push(new Script(stmt.row));

     return scripts;

   },

   getScriptsForURI: function(aURI) {

     var scripts = [];

     var stmt = this.db.createStatement("SELECT DISTINCT id, name, version, author, description, uri, enabled, script FROM script JOIN include ON script.id=include.script_id WHERE :uri GLOB address AND enabled=1");

     stmt.params.uri = aURI.spec;

     while (stmt.executeStep())

       scripts.push(new Script(stmt.row));

     return scripts;

   },

   hasScript: function(aURI) {

     var stmt = this.db.createStatement("SELECT COUNT() AS count FROM script WHERE uri=:uri");

     stmt.params.uri = aURI.spec;

     if (stmt.executeStep())

       return stmt.row.count > 0;

     return false;

   },

   installScript: function(aScript, aURI) {

     try {

       var data = {

         name: "",

         author: "",

         description: "",

         uri: aURI.spec,

         enabled: 1,

         script: aScript

       };

       var includes = [];

       var stmt = this.db.createStatement("INSERT INTO script VALUES (NULL, :name, :version, :author, :description, :uri, :enabled, :script)");

       stmt.params.uri = aURI.spec;

       stmt.params.enabled = 1;

       stmt.params.script = aScript;

       var start = aScript.indexOf("==UserScript==");

       var end = aScript.indexOf("==/UserScript==");

       if (start < 0 || end < 0)

         return;

       LOG("Looking for tags in " + aScript.substring(start, end));

       var lines = aScript.substring(start, end).split("\n");

       var pos = 0;

       while (pos < lines.length) {

         var matches = TAGMATCH.exec(lines[pos]);

         if (matches) {

           LOG("Tag: " + matches[1] + " = " + matches[2]);

           switch (matches[1]) {

           case "name":

           case "description":

           case "author":

           case "version":

             stmt.params[matches[1]] = matches[2];

             data[matches[1]] = matches[2];

             break;

           case "include":

             includes.push(matches[2]);

             break;

           }

         }

         pos++;

       }

       stmt.execute();

       var id = this.db.lastInsertRowID;

       stmt = this.db.createStatement("INSERT INTO include VALUES (:id, :address)");

       includes.forEach(function(aInclude) {

         stmt.params.id = id;

         stmt.params.address = aInclude;

         stmt.execute();

       });

       AddonManagerPrivate.callInstallListeners("onNewInstall", null,

                                                 new Script(data), null, false);

     }

     catch (e) {

       LOGE("Exception installing script", e);

     }

   },

   uninstallScript: function(aScript) {

     AddonManagerPrivate.callAddonListeners("onUninstalling", aScript, false);

     var stmt = this.db.createStatement("DELETE FROM script WHERE id=:id");

     stmt.params.id = aScript._id;

     stmt.execute();

     AddonManagerPrivate.callAddonListeners("onUninstalled", aScript);

   },

   updateDisabledState: function(aScript) {

     var stmt = this.db.createStatement("UPDATE script SET enabled=:enabled WHERE id=:id");

     stmt.params.id = aScript._id;

     stmt.params.enabled = aScript.enabled;

     stmt.execute();

   },

   shutdown: function() {

     this.db.asyncClose();

   }

 };

 function Script(aData) {

   this.id = aData.id + ID_SUFFIX;

   this._id = aData.id;

   this.name = aData.name;

   this.version = aData.version;

   this.creator = aData.author;

   this.description = aData.description;

   this.homepageURL = aData.uri;

   this.enabled = aData.enabled;

   this.script = aData.script;

 }

 Script.prototype = {

   _id: null,

   version: null,

   type: "user-script",

   isCompatible: true,

   providesUpdatesSecurely: true,

   blocklistState: 0,

   appDisabled: false,

   scope: AddonManager.SCOPE_PROFILE,

   isActive: true,

   pendingOperations: 0,

   name: null,

   version: null,

   description: null,

   creator: null,

   homepageURL: null,

   script: null,

   get userDisabled() {

     return this.enabled != 1;

   },

   set userDisabled(val) {

     if (val == this.userDisabled)

       return val;

     AddonManagerPrivate.callAddonListeners(val ? "onEnabling" : "onDisabling",

                                            this, false);

     this.enabled = val ? 0 : 1;

     ScriptDatabase.updateDisabledState(this);

     AddonManagerPrivate.callAddonListeners(val ? "onEnabled" : "onDisabled",

                                            this);

   },

   get permissions() {

     var perms = AddonManager.PERM_CAN_UNINSTALL;

     perms |= this.userDisabled ? AddonManager.PERM_CAN_ENABLE : AddonManager.PERM_CAN_DISABLE;

     return perms;

   },

   isCompatibleWith: function() {

     return true;

   },

   findUpdates: function(aListener) {

     if ("onNoCompatibilityUpdateAvailable" in aListener)

       aListener.onNoCompatibilityUpdateAvailable(this);

     if ("onNoUpdateAvailable" in aListener)

       aListener.onNoUpdateAvailable(this);

     if ("onUpdateFinished" in aListener)

       aListener.onUpdateFinished(this);

   },

   uninstall: function() {

     ScriptDatabase.uninstallScript(this);

   }

 };

 ScriptDatabase.startup();