From 443a6331e6792f4758d5a3b83ba2576e6897138d Mon Sep 17 00:00:00 2001
From: Robin Malley <rmalley@cock.li>
Date: Mon, 20 Feb 2023 05:06:36 +0000
Subject: [PATCH] Continue expanding addon system

---
 conf/smr.conf.in                   |  1 +
 src/lua/endpoints/download_get.lua | 19 +++++++++++++
 src/lua/hooks.lua                  | 45 ++++++++++++++++++++++++++++++
 src/pages/read.etlua.in            | 17 +++++++----
 4 files changed, 76 insertions(+), 6 deletions(-)
 create mode 100644 src/lua/hooks.lua

diff --git a/conf/smr.conf.in b/conf/smr.conf.in
index 277597f..1f5ede4 100644
--- a/conf/smr.conf.in
+++ b/conf/smr.conf.in
@@ -156,6 +156,7 @@ domain * {
 
 		validate qs:get story v_storyid
 		validate qs:get pwd v_hex_128
+		validate qs:get fmt v_any
 	}
 
 	route /_preview {
diff --git a/src/lua/endpoints/download_get.lua b/src/lua/endpoints/download_get.lua
index c2b1af2..18c86b5 100644
--- a/src/lua/endpoints/download_get.lua
+++ b/src/lua/endpoints/download_get.lua
@@ -5,6 +5,7 @@ local db = require("db")
 local queries = require("queries")
 local util = require("util")
 local pages = require("pages")
+local api = require("hooks")
 
 local stmnt_download
 local oldconfigure = configure
@@ -13,6 +14,24 @@ function configure(...)
 	return oldconfigure(...)
 end
 
+local oldget = api.get.page_reader
+api.get.page_reader = function(env)
+	local ret = oldget(env)
+	local button = {
+		endpoint = string.format("https://%s/_download",env.domain),
+		method = "GET",
+		fields = {
+			story = env.short,
+		},
+		text = "Download TXT"
+	}
+	if env.unlisted then
+		button.fields.pwd = env.hashstr
+	end
+	table.insert(ret,button)
+	return ret
+end
+
 local function download_get(req)
 	local host = http_request_get_host(req)
 	local path = http_request_get_path(req)
diff --git a/src/lua/hooks.lua b/src/lua/hooks.lua
new file mode 100644
index 0000000..cef8daf
--- /dev/null
+++ b/src/lua/hooks.lua
@@ -0,0 +1,45 @@
+--[[
+Global functions that smr exposes that can be overriden by addons
+]]
+
+local api = {}
+
+-- Called before any request processing. Returning true "traps" the request, and
+-- does not continue calling smr logic, or logic of any other addons.
+api.pre_request = function(req) end
+
+-- Called after smr request processing. Returning true "traps" the request, and
+-- does not continue calling any other addon logic. This will not stop smr from
+-- responding to the request, since by this time http_request_response() has
+-- already been called.
+api.post_request = function(req) end
+
+-- Called during startup of the worker process
+-- Failures in this function will prevent kore from starting.
+-- Return value is ignored.
+api.worker_init = function() end
+
+-- Called during shutdown of the worker process
+-- Failures in this function cause other addon hooks to this function to be skipped.
+-- Return value is ignored.
+api.worker_shutdown = function() end
+
+-- The following are tables and their options:
+-- "buttonspec" - specifies a button to display on the front end, has the fields:
+-- 	.endpoint - the url to go to when the button is pressed
+-- 	.method - the HTTP method to use to call the endpoint
+-- 	.fields - key/value pairs to send as arguments when calling the endpoint
+-- 		  These are usually "hidden" fields for a form.
+-- 	.text - The text that displays on the button
+
+-- Called to display configuration as html.
+api.get = {
+	-- returns an array of buttonspec, displayed at the top of a story,
+	-- only for the logged in owner of a story.
+	page_owner = function(env) return {} end,
+
+	-- returns an array of buttonspec, displayed at the bottom of a story
+	page_reader = function(env) return {} end,
+}
+
+return api
diff --git a/src/pages/read.etlua.in b/src/pages/read.etlua.in
index d095ea0..9f9afec 100644
--- a/src/pages/read.etlua.in
+++ b/src/pages/read.etlua.in
@@ -37,13 +37,18 @@
 
 <p><%= views %> Hits</p>
 
-<form action="https://<%= domain %>/_download" method="get">
-	<input type="hidden" name="story" value="<%= short %>"/>
-	<% if unlisted then %>
-		<input type="hidden" name="pwd" value="<%= hashstr %>"/>
+<div class="row">
+<% for _, spec in ipairs(api.get.page_reader(getfenv(1))) do %>
+	<form action="<%= spec.endpoint %>" method="<%= spec.method %>"><fieldset>
+	<% for key, value in pairs(spec.fields) do %>
+		<input type="hidden" name="<%= key %>" value="<%= value %>"/>
 	<% end %>
-	<input type="submit" value="Download TXT" class="button"/>
-</form>
+		
+	<input type="submit" value="<%= spec.text %>" class="button">
+	</fieldset></form>
+<% end %>
+</div>
+
 <% if not show_comments then -%>
 	<form action="https://<%= domain %>/<%= short %>"><fieldset>
 		<input type="hidden" name="comments" value="1">