initial: basic line parser

1 files changed, 64 insertions, 0 deletions

diff --git a/cal.lua b/cal.lua
new file mode 100755
index 0000000..7fcbbed
--- /dev/null
+++ b/cal.lua
@@ -0,0 +1,64 @@
+#!/usr/bin/env lua
+
+local io            = require "io"
+local ioopen        = io.open
+
+local string        = require "string"
+local stringformat  = string.format
+
+local println       = function (...) print (stringformat (...)) end
+
+local parse_calendar do
+  local lpeg            = require "lpeg"
+  local lpegmatch       = lpeg.match
+  local P               = lpeg.P
+  local C               = lpeg.C
+  local Cp              = lpeg.Cp
+
+  local p_cr            = P"\r"
+  local p_lf            = P"\n"
+  local p_eol           = p_cr * p_lf + p_lf
+  local p_noeol         = P(1) - p_eol
+
+  local p_content_line  = C (p_noeol^1) * p_eol * Cp ()
+
+  local parse_content_line = function (raw, pos0)
+    local res, pos1 = lpegmatch (p_content_line, raw, pos0)
+
+    return res, pos1
+  end
+
+  parse_calendar = function (raw, pos0, consumed)
+    if pos0 == nil then return parse_calendar (raw, 1, 0) end
+
+    local cline, pos1 = parse_content_line (raw, pos0)
+    println ("»»» [%d–%d] [%s]", pos0, pos1, cline)
+    return parse_calendar (raw, pos1, consumed + pos1 - pos0)
+  end
+end
+
+local print_calendar do
+end
+
+local loaddata = function (fname)
+  local fh = ioopen (fname, "r")
+
+  if fh == nil then
+    error ("could not open file " .. fname .. " for reading")
+  end
+
+  return fh:read ("*a")
+end
+
+local main = function (argv)
+  if #argv ~= 1 then
+    error "pass me a file name, I insist!"
+  end
+
+  local raw = loaddata (argv [1])
+
+  return parse_calendar (raw)
+end
+
+return main (arg)
+