1 files changed, 64 insertions, 0 deletions
diff --git a/log.lua b/log.lua
new file mode 100644
index 0000000..c1c36a7
--- /dev/null
+++ b/log.lua
@@ -0,0 +1,64 @@
+--- Simple logging module for vis-lspc.
+-- @module log
+-- @author Florian Fischer
+-- @license GPL-3
+-- @copyright 2024 Florian Fischer
+local log = {}
+
+--- Logger class metatable.
+local Logger = {}
+function Logger:log(msg)
+  self.log_fd:write(msg)
+  self.log_fd:write('\n')
+  self.log_fd:flush()
+end
+function Logger:close()
+  self.log_fd:close()
+end
+
+--- Dummy logger class metatable using NOP log functions.
+local DummyLogger = {}
+function DummyLogger:log()
+end
+function DummyLogger:close()
+end
+
+function log.new(name, logging, log_file)
+  local logger = {name = name, log_fd = nil}
+
+  if not logging then
+    setmetatable(logger, {__index = DummyLogger})
+    return logger
+  end
+
+  setmetatable(logger, {__index = Logger})
+
+  -- open the default log file in $XDG_DATA_HOME/vis-lspc
+  if not log_file then
+    local xdg_data = os.getenv('XDG_DATA_HOME') or os.getenv('HOME') .. '/.local/share'
+    local log_dir = xdg_data .. '/vis-lspc'
+
+    -- ensure the direcoty exists
+    os.execute('mkdir -p ' .. log_dir)
+
+    -- log file format: {timestamp}-{basename-cwd}.log
+    local log_file_fmt = log_dir .. '/%s-%s.log'
+    local timestamp = os.date('%Y-%m-%dT%H:%M:%S')
+    local proc = assert(io.popen('basename "${PWD}"', 'r'))
+    local basename_cwd = assert(proc:read('*a')):match('^%s*(.-)%s*$')
+    local success, _, status = proc:close()
+    if not success then
+      local err = 'getting the basename of CWD failed with exit code: ' .. status
+      vis:info('LSPC Error: ' .. err)
+    end
+    log_file = log_file_fmt:format(timestamp, basename_cwd)
+
+  elseif type(log_file) == 'function' then
+    log_file = log_file()
+  end
+
+  logger.log_fd = assert(io.open(log_file, 'w'))
+  return logger
+end
+
+return log