From eee9ce71bd0e84859e5d3a5135fe4f4265d331da Mon Sep 17 00:00:00 2001
From: Toby Vincent <tobyv@tobyvin.dev>
Date: Sat, 21 Oct 2023 21:47:26 -0500
Subject: feat: parse full headers

This manually parses the headers from message. It complicates both
parsing and displaying the headers.
---
 lua/inbox/config.lua           |  2 ++
 lua/inbox/indexers/notmuch.lua |  9 +++++++++
 lua/inbox/types.lua            |  2 +-
 lua/inbox/utils.lua            | 30 ++++++++++++++++++++++++++++++
 lua/inbox/view.lua             | 23 +++++++++++++++--------
 5 files changed, 57 insertions(+), 9 deletions(-)

diff --git a/lua/inbox/config.lua b/lua/inbox/config.lua
index 634b35d..2f7f47d 100644
--- a/lua/inbox/config.lua
+++ b/lua/inbox/config.lua
@@ -1,3 +1,5 @@
+local utils = require("inbox.utils")
+
 ---@type inbox.Config
 local default_config = {
 	indexer_config = "notmuch",
diff --git a/lua/inbox/indexers/notmuch.lua b/lua/inbox/indexers/notmuch.lua
index a05c112..a06991a 100644
--- a/lua/inbox/indexers/notmuch.lua
+++ b/lua/inbox/indexers/notmuch.lua
@@ -157,6 +157,15 @@ function M.show_id(id)
 		entry = entry[1] --[[@as inbox.Notmuch.Entry]]
 	end
 
+	job = Job:new({
+		command = "notmuch",
+		args = { "show", "--part=0", ("id:%s"):format(id) },
+	})
+
+	local lines = job:sync()
+	local headers = utils.parse_headers(lines)
+
+	entry.headers = headers
 	entry.tags = M.parse_tags(entry.tags)
 	entry.parts = {}
 	for _, part in pairs(M.flatten_parts(entry.body[1])) do
diff --git a/lua/inbox/types.lua b/lua/inbox/types.lua
index a4105b0..4a7efe9 100644
--- a/lua/inbox/types.lua
+++ b/lua/inbox/types.lua
@@ -48,7 +48,7 @@
 ---@field filename string[]
 ---@field tags string[]
 ---@field parts inbox.EntryPart[]
----@field headers table<inbox.HeaderKey, string>
+---@field headers table<inbox.HeaderKey, string[]>
 
 ---@class inbox.EntryPart
 ---@field id integer
diff --git a/lua/inbox/utils.lua b/lua/inbox/utils.lua
index 8d82b7d..e9826c8 100644
--- a/lua/inbox/utils.lua
+++ b/lua/inbox/utils.lua
@@ -150,6 +150,36 @@ function M.json_decode(json)
 	return results
 end
 
+---@param lines string[]
+---@return table<inbox.HeaderKey, string[]> headers
+function M.parse_headers(lines)
+	local headers = {}
+
+	local cur_header
+	for _, line in pairs(lines) do
+		if line == "" then
+			break
+		end
+
+		local header, value = line:match("^([A-Z][^: ]*): (.*)")
+
+		if header then
+			cur_header = header
+			headers[cur_header] = {}
+		else
+			value = line
+		end
+
+		if cur_header then
+			table.insert(headers[cur_header], value)
+		else
+			M.error("Failed to parse line in headers", { line = line })
+		end
+	end
+
+	return headers
+end
+
 ---@param bufnr integer
 ---@return string? maildir maildir name
 ---@return string? id entry id
diff --git a/lua/inbox/view.lua b/lua/inbox/view.lua
index 3ba20c6..a72f3f2 100644
--- a/lua/inbox/view.lua
+++ b/lua/inbox/view.lua
@@ -175,17 +175,24 @@ function M.render_headers(bufnr, id)
 
 	local lines = {}
 
-	for _, name in pairs(config.headers) do
-		if entry.headers[name] ~= nil then
-			table.insert(lines, ("%s: %s"):format(name, entry.headers[name]))
+	local headers = {}
+	if vim.b[bufnr].show_all_headers then
+		headers = entry.headers
+	else
+		for _, name in pairs(config.headers) do
+			if entry.headers[name] ~= nil then
+				headers[name] = entry.headers[name]
+			end
 		end
 	end
 
-	if vim.b[bufnr].show_all_headers then
-		for name, value in pairs(entry.headers) do
-			if not vim.tbl_contains(config.headers, name) then
-				table.insert(lines, ("%s: %s"):format(name, value))
-			end
+	for name, value in pairs(headers) do
+		local i, line = next(value)
+		table.insert(lines, ("%s: %s"):format(name, line))
+		i, line = next(value, i)
+		while i ~= nil do
+			table.insert(lines, line)
+			i, line = next(value, i)
 		end
 	end
 
-- 
cgit v1.2.3-70-g09d2