feat: impl headers and handle multipart messages

6 files changed, 287 insertions, 121 deletions

diff --git a/lua/inbox/config.lua b/lua/inbox/config.lua
index 9ac9900..4692f5c 100644
--- a/lua/inbox/config.lua
+++ b/lua/inbox/config.lua
@@ -1,20 +1,7 @@
----@class inbox.Config
----@field indexer_config inbox.Indexer.Config|nil
----@field buf_options table|nil
----@field win_options table|nil
----@field columns integer[]
----@field flags table<string, table>
-
 ---@type inbox.Config
 local default_config = {
 	indexer_config = "notmuch",
-	buf_options = {
-		buftype = "acwrite",
-		syntax = "inbox",
-		filetype = "inbox",
-		buflisted = false,
-		bufhidden = "hide",
-	},
+	buf_options = {},
 	win_options = {
 		wrap = false,
 		signcolumn = "yes:1",
@@ -28,6 +15,11 @@ local default_config = {
 		15,
 		30,
 	},
+	headers = {
+		"From",
+		"Date",
+		"Subject",
+	},
 	flags = {
 		unread = {
 			text = "O",
diff --git a/lua/inbox/indexers/notmuch.lua b/lua/inbox/indexers/notmuch.lua
index 5b3e48c..5e998eb 100644
--- a/lua/inbox/indexers/notmuch.lua
+++ b/lua/inbox/indexers/notmuch.lua
@@ -27,23 +27,21 @@ local default_config = {
 ---@field timestamp integer
 ---@field total integer
 
----@class inbox.Notmuch.Entry
----@field id string
+---@class inbox.Notmuch.Entry: inbox.Entry
 ---@field filename string[]
----@field timestamp integer
 ---@field date_relative string?
----@field tags string[]
 ---@field duplicate integer
 ---@field body inbox.EntryPart[]
 ---@field crypto table
----@field headers inbox.Headers
----@field parts  inbox.EntryPart
 
 ---@type inbox.Indexer.Notmuch
 local M = {
 	_cache = {},
 }
 
+---@private
+---@param id string
+---@return inbox.Notmuch.Entry | nil
 function M.cache(id)
 	if M._cache[id] == nil then
 		M._cache[id] = M.show_id(id)
@@ -59,16 +57,16 @@ end
 function M.index(maildir, callback, opts)
 	opts = opts or {}
 
-	local json = ""
+	local sbuf = {}
 	local job = Job:new({
 		command = "notmuch",
 		args = { "search", "--format=json" },
 		on_stdout = vim.schedule_wrap(function(_, stdout)
-			json = json .. stdout
+			table.insert(sbuf, stdout)
 		end),
 		on_exit = vim.schedule_wrap(function()
 			---@type inbox.Notmuch.SearchResult[]
-			local results = utils.json_decode(json)
+			local results = utils.json_decode(table.concat(sbuf, "\n"))
 
 			---@type inbox.Summary[]
 			local entries = {}
@@ -165,31 +163,15 @@ function M.show_id(id)
 
 	entry.tags = M.parse_tags(entry.tags)
 	entry.parts = M.flatten_parts(entry.body[1])
+	table.sort(entry.parts, function(a, b)
+		return a.id < b.id
+	end)
 
 	return entry
 end
 
----@param id string
----@return inbox.Entry?
 function M.get_entry(id)
-	local entry = M.cache(id)
-	if entry == nil then
-		return nil
-	end
-
-	local parts = vim.tbl_map(function(part)
-		return part["content-type"]
-	end, entry.parts)
-
-	---@type inbox.Entry
-	return {
-		id = entry.id,
-		timestamp = entry.timestamp,
-		filename = entry.filename[1],
-		tags = entry.tags,
-		parts = parts,
-		headers = entry.headers,
-	}
+	return M.cache(id)
 end
 
 function M.flatten_parts(part, parts)
@@ -215,40 +197,41 @@ function M.get_part(id, content_type, callback)
 
 	if entry == nil then
 		vim.notify(("Failed to get entry with id: %s"):format(id), vim.log.levels.ERROR)
-		return nil
+		return
 	end
 
-	---@type inbox.EntryPart?
-	local part
-	if content_type == nil then
-		for _, p in pairs(entry.parts) do
-			if part == nil or p.id < part.id then
-				part = p
-			end
-		end
-	else
-		for _, p in pairs(entry.parts) do
-			if p["content-type"] ~= content_type then
-				part = p
+	local parts = entry.parts
+
+	local index = 1
+	if content_type ~= nil then
+		for i, p in pairs(entry.parts) do
+			if p["content-type"] == content_type then
+				index = i
 				break
 			end
 		end
+	else
+		index = 1
 	end
 
+	local part = parts[index]
+
+	---@type inbox.EntryPart?
+
 	if part == nil then
 		vim.notify(("Failed to find message part for entry id: %s"):format(id), vim.log.levels.ERROR)
-		return nil
+		return
 	end
 
-	local stdout = {}
+	local sbuf = {}
 	local job = Job:new({
 		command = "notmuch",
 		args = { "show", ("--part=%s"):format(part.id), ("id:%s"):format(entry.id) },
-		on_stdout = vim.schedule_wrap(function(_, data)
-			table.insert(stdout, data)
+		on_stdout = vim.schedule_wrap(function(_, stdout)
+			table.insert(sbuf, stdout)
 		end),
 		on_exit = vim.schedule_wrap(function()
-			callback(part["content-type"], stdout)
+			callback(entry, index, sbuf)
 		end),
 	})
 
diff --git a/lua/inbox/init.lua b/lua/inbox/init.lua
index bb59fc4..f3869c0 100644
--- a/lua/inbox/init.lua
+++ b/lua/inbox/init.lua
@@ -22,7 +22,7 @@ function M.select()
 			end
 		end
 	else
-		local entry = M.get_cursor_entry()
+		local entry = M.get_id_on_cursor()
 		if entry then
 			table.insert(entries, entry)
 		end
@@ -31,21 +31,79 @@ end
 
 function M.open(maildir)
 	local view = require("inbox.view")
-	if M.bufnr == nil then
-		M.bufnr = view.initialize(maildir)
+
+	if M.buffers[maildir] == nil or vim.api.nvim_buf_is_valid(M.buffers[maildir]) then
+		M.buffers[maildir] = view.initialize_inbox(maildir)
 	end
 
-	if not vim.api.nvim_buf_is_valid(M.bufnr) then
-		--- TODO: Handle error
-		return
+	vim.api.nvim_set_current_buf(M.buffers[maildir])
+end
+
+function M.open_entry(id, content_type)
+	if id == nil then
+		id = M.get_cursor_id()
+		if id == nil then
+			return nil
+		end
+	end
+
+	if M.buffers[id] == nil or vim.api.nvim_buf_is_valid(M.buffers[id]) then
+		local utils = require("inbox.utils")
+		local view = require("inbox.view")
+
+		local maildir = utils.parse_scheme(0)
+		if maildir == nil then
+			return
+		end
+
+		local bufnr = view.initialize_entry(maildir, id, content_type)
+		M.buffers[id] = bufnr
+	end
+
+	vim.api.nvim_set_current_buf(M.buffers[id])
+end
+
+function M.select_part()
+	local entry = M.get_cursor_entry()
+
+	if entry == nil then
+		return nil
 	end
 
-	vim.api.nvim_set_current_buf(M.bufnr)
+	vim.ui.select(entry.parts, {
+		prompt = "Part",
+		format_item = function(item)
+			return item["content-type"]
+		end,
+	}, function(part)
+		M.open_entry(entry.id, part)
+	end)
 end
 
-function M.open_entry(part)
+function M.toggle_headers(bufnr)
 	local view = require("inbox.view")
 
+	if bufnr == nil or bufnr == 0 then
+		bufnr = vim.api.nvim_get_current_buf()
+	end
+
+	local id = vim.b[bufnr].inbox_id
+
+	if id == nil then
+		return
+	end
+
+	if vim.b[bufnr].show_all_headers then
+		vim.b[bufnr].show_all_headers = false
+	else
+		vim.b[bufnr].show_all_headers = true
+	end
+
+	view.render_headers(bufnr, id)
+end
+
+---@return string? id
+function M.get_cursor_id()
 	local lnum = vim.api.nvim_win_get_cursor(0)[1]
 	local id = vim.b[0].inbox_ids[lnum]
 
@@ -54,27 +112,21 @@ function M.open_entry(part)
 		return nil
 	end
 
-	local bufnr = view.render_entry(id, part)
+	return id
+end
 
-	if bufnr ~= nil then
-		vim.api.nvim_set_current_buf(bufnr)
+---@return inbox.Entry? entry
+function M.get_cursor_entry()
+	local id = M.get_cursor_id()
+	if id == nil then
+		vim.notify(("Failed to get entry with id: %s"):format(id), vim.log.levels.ERROR)
+		return nil
 	end
-end
 
-function M.open_part()
 	local indexers = require("inbox.indexers")
 	local indexer = indexers.get_indexer()
-	local lnum = vim.api.nvim_win_get_cursor(0)[1]
-	local id = vim.b[0].inbox_ids[lnum]
 
-  -- FIX: fails to open selected part.
-	local parts = indexer.get_entry(id).parts
-	if vim.tbl_isempty(parts) then
-		vim.notify(("Failed to get parts for entry id: %s"):format(id), vim.log.levels.ERROR)
-		return nil
-	end
-
-	vim.ui.select(parts, {}, M.open_entry)
+	return indexer.get_entry(id)
 end
 
 ---@param opts inbox.Config
@@ -90,6 +142,8 @@ function M.setup(opts)
 		local name = utils.sign_name(sign)
 		vim.fn.sign_define(name, value)
 	end
+
+	M.augroup = vim.api.nvim_create_augroup("Inbox", { clear = true })
 end
 
 return M
diff --git a/lua/inbox/types.lua b/lua/inbox/types.lua
index b87991e..4a3d320 100644
--- a/lua/inbox/types.lua
+++ b/lua/inbox/types.lua
@@ -1,6 +1,12 @@
----@alias inbox.Headers table<inbox.Header, string>
+---@class inbox.Config
+---@field indexer_config inbox.Indexer.Config|nil
+---@field buf_options table|nil
+---@field win_options table|nil
+---@field columns integer[]
+---@field flags table<string, table>
+---@field headers inbox.HeaderKey[]
 
----@alias inbox.Header
+---@alias inbox.HeaderKey
 ---| "Subject"
 ---| "Date"
 ---| "To"
@@ -18,7 +24,7 @@
 ---@field index? fun(maildir: string, cb: fun(ids: string[], entries: inbox.Summary[], signs: (string | integer)[][]), opts?: table)
 ---@field get_entry? fun(id: string): inbox.Entry|nil
 ---@field get_parts? fun(id: string): inbox.ContentType[]
----@field get_part? fun(id: string, content_type: inbox.ContentType, callback: fun(content_type: inbox.ContentType, lines: string[]))
+---@field get_part? fun(id: string, content_type: inbox.ContentType, callback: fun(entry: inbox.Entry, part_index: integer, part_lines: string[]))
 
 ---@alias inbox.Indexer.Config
 ---| "notmuch"
@@ -34,10 +40,10 @@
 ---@class inbox.Entry
 ---@field id string
 ---@field timestamp integer
----@field filename string
+---@field filename string[]
 ---@field tags string[]
----@field parts string[]
----@field headers inbox.Headers
+---@field parts inbox.EntryPart[]
+---@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 3b84b83..c5954a8 100644
--- a/lua/inbox/utils.lua
+++ b/lua/inbox/utils.lua
@@ -111,6 +111,8 @@ function M.set_signs(bufnr, signs)
 	end
 end
 
+---@param json string
+---@return table data
 function M.json_decode(json)
 	local results = {}
 	if json and json ~= "" then
@@ -119,4 +121,29 @@ function M.json_decode(json)
 	return results
 end
 
+---@param bufnr integer
+---@return string? maildir maildir name
+---@return string? id entry id
+function M.parse_scheme(bufnr)
+	local bufname = vim.api.nvim_buf_get_name(bufnr or 0)
+
+	local _, init, maildir = bufname:find("maildir://([^:]+)")
+	local _, _, id = bufname:find(":(.*)", init)
+
+	return maildir, id
+end
+
+function M.stateful_iter(table, wrap)
+	local k
+	local s_k, s_v = next(table)
+	return function()
+		local v
+		k, v = next(table, k)
+		if k == nil and wrap then
+			k, v = s_k, s_v
+		end
+		return k, v
+	end
+end
+
 return M
diff --git a/lua/inbox/view.lua b/lua/inbox/view.lua
index e770417..a79bf17 100644
--- a/lua/inbox/view.lua
+++ b/lua/inbox/view.lua
@@ -4,32 +4,64 @@ local utils = require("inbox.utils")
 
 local M = {}
 
----@param bufname string
+---@param path string
 ---@param buf_options table<string, any> | nil
 ---@return integer bufnr
-function M.create_buffer(bufname, buf_options)
+function M.create_buffer(path, buf_options)
 	local bufnr = vim.api.nvim_create_buf(true, false)
 
 	for k, v in pairs(buf_options or {}) do
 		vim.api.nvim_buf_set_option(bufnr, k, v)
 	end
 
+	local bufname = string.format("maildir://%s", path)
+
 	vim.api.nvim_buf_set_name(bufnr, bufname)
 
 	return bufnr
 end
 
+function M.render_buffer(bufnr)
+	local maildir, id = utils.parse_scheme(bufnr)
+
+	if maildir == nil then
+		vim.notify(("Buffer is not a valid maildir buffer: %s"):format(bufnr), vim.log.levels.ERROR)
+	elseif id ~= nil and id ~= "" then
+		M.render_entry(bufnr, id)
+	else
+		M.render_inbox(bufnr, maildir)
+	end
+end
+
+---@param bufnr integer
+---@param lines string[]
+---@param start integer?
+---@param end_ integer?
+function M.set_buffer_content(bufnr, lines, start, end_)
+	if start == nil then
+		start = 0
+	end
+
+	if end_ == nil then
+		end_ = -1
+	end
+
+	vim.bo[bufnr].modifiable = true
+	vim.api.nvim_buf_set_lines(bufnr, start, end_, true, lines)
+	vim.bo[bufnr].modifiable = false
+	vim.bo[bufnr].modified = false
+end
+
 ---@param maildir string
 ---@return integer bufnr
-function M.initialize(maildir)
+function M.initialize_inbox(maildir)
 	local buf_options = vim.tbl_extend("keep", config.buf_options, {
 		buftype = "acwrite",
 		syntax = "inbox",
 		filetype = "inbox",
 	})
 
-	local bufname = string.format("maildir://%s", maildir)
-	local bufnr = M.create_buffer(bufname, buf_options)
+	local bufnr = M.create_buffer(maildir, buf_options)
 
 	-- vim.api.nvim_clear_autocmds({ buffer = bufnr, group = "Inbox" })
 
@@ -40,20 +72,6 @@ function M.initialize(maildir)
 	return bufnr
 end
 
-function M.render_buffer_content(bufnr, lines, highlights, signs)
-	vim.bo[bufnr].modifiable = true
-	vim.api.nvim_buf_set_lines(bufnr, 0, -1, true, lines)
-	vim.bo[bufnr].modifiable = false
-	vim.bo[bufnr].modified = false
-
-	if highlights then
-		utils.set_highlights(bufnr, highlights)
-	end
-	if signs then
-		utils.set_signs(bufnr, signs)
-	end
-end
-
 ---@param bufnr integer
 function M.render_inbox(bufnr, maildir)
 	local indexer = indexers.get_indexer()
@@ -66,7 +84,9 @@ function M.render_inbox(bufnr, maildir)
 			vim.api.nvim_set_option_value(k, v, { scope = "local", win = winid })
 		end
 
-		M.render_buffer_content(bufnr, lines, highlights, signs)
+		M.set_buffer_content(bufnr, lines)
+		utils.set_highlights(bufnr, highlights)
+		utils.set_signs(bufnr, signs)
 
 		vim.api.nvim_set_option_value(
 			"winbar",
@@ -79,19 +99,103 @@ function M.render_inbox(bufnr, maildir)
 	end)
 end
 
-function M.render_entry(id, content_type)
+---@param maildir string
+---@param id string
+---@param content_type string
+---@return integer? bufnr
+function M.initialize_entry(maildir, id, content_type)
+	local bufname = ("%s:%s"):format(maildir, id)
+	local bufnr = M.create_buffer(bufname, {
+		syntax = "mail",
+		filetype = "mail",
+	})
+
+	vim.api.nvim_clear_autocmds({ buffer = bufnr, group = require("inbox").augroup })
+
+	vim.api.nvim_create_autocmd("BufDelete", {
+		group = "Inbox",
+		buffer = bufnr,
+		callback = function()
+			require("inbox").buffers[id] = nil
+		end,
+	})
+
+	vim.keymap.set("n", "q", function()
+		vim.api.nvim_buf_delete(bufnr, {})
+	end, { buffer = bufnr })
+
+	vim.keymap.set("n", "<C-h>", require("inbox").toggle_headers, { buffer = bufnr })
+	vim.keymap.set("n", "<C-n>", function()
+		local k, v = next(vim.b[bufnr].inbox_parts, vim.b[bufnr].inbox_part_index)
+		if k == nil then
+			k, v = next(vim.b[bufnr].inbox_parts)
+		end
+		M.render_entry(bufnr, id, v["content-type"])
+	end, { buffer = bufnr })
+
+	vim.b[bufnr].inbox_id = id
+	vim.b[bufnr].header_filter = config.headers
+
+	M.render_headers(bufnr, id)
+	M.render_entry(bufnr, id, content_type)
+
+	return bufnr
+end
+
+function M.render_headers(bufnr, id)
 	local indexer = indexers.get_indexer()
-	local bufname = string.format("%s [%s]", id, content_type)
-	local bufnr = M.create_buffer(bufname, {})
-
-	indexer.get_part(id, content_type, function(ct, lines)
-		content_type = content_type or ct
-		bufname = string.format("%s [%s]", id, content_type)
-		vim.api.nvim_buf_set_name(bufnr, bufname)
-		M.render_buffer_content(bufnr, lines)
-	end)
+	local entry = indexer.get_entry(id)
+
+	if entry == nil then
+		return
+	end
+
+	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]))
+		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
+		end
+	end
 
-	vim.api.nvim_set_current_buf(bufnr)
+	table.insert(lines, "")
+
+	local cursor_pos = vim.fn.getpos(".")
+
+	if vim.b[bufnr].header_count ~= nil then
+		M.set_buffer_content(bufnr, {}, 0, vim.b[bufnr].header_count)
+	end
+
+	M.set_buffer_content(bufnr, lines, 0, 0)
+
+	vim.b[bufnr].header_count = #lines
+
+	vim.fn.setpos(".", cursor_pos)
+end
+
+function M.render_entry(bufnr, id, content_type)
+	local indexer = indexers.get_indexer()
+
+	indexer.get_part(id, content_type, function(entry, index, lines)
+		M.set_buffer_content(bufnr, lines, vim.b[bufnr].header_count)
+		vim.b[bufnr].inbox_parts = entry.parts
+		vim.b[bufnr].inbox_part_index = index
+
+		local winid = vim.api.nvim_get_current_win()
+		vim.api.nvim_set_option_value(
+			"winbar",
+			vim.b[bufnr].inbox_parts[vim.b[bufnr].inbox_part_index]["content-type"],
+			{ scope = "local", win = winid }
+		)
+	end)
 end
 
 return M