-- USAGE:
--
--    # Optional: Delete cache to get latest terminfo from internet.
--    rm -rf /tmp/nvim_terminfo/
--
--    # Optional: Ensure the latest ncurses+tic is in your PATH.
--    export PATH="/opt/homebrew/Cellar/ncurses/6.5/bin/":"$PATH"
--
--    nvim -l src/gen/gen_terminfo.lua
--
-- This script does:
--
--   1. Download Dickey's terminfo.src
--   2. Compile temporary terminfo database from terminfo.src
--   3. Use database to generate src/nvim/tui/terminfo_defs.h

local url = 'https://invisible-island.net/datafiles/current/terminfo.src.gz'
local target_gen = 'src/nvim/tui/terminfo_builtin.h'
local target_enum = 'src/nvim/tui/terminfo_enum_defs.h'

local terminfo = require('src.gen.terminfo')
local entries = terminfo.builtin_terminals
local wanted_strings = terminfo.fields.strings
local wanted_strings_ext = terminfo.fields.strings_ext
local wanted_bools = terminfo.fields.bools
local wanted_ints = terminfo.fields.ints
local wanted_termkeys = terminfo.fields.termkeys

local db = '/tmp/nvim_terminfo'
if vim.uv.fs_stat(db) == nil then
  local function sys(cmd)
    print(cmd)
    os.execute(cmd)
  end
  sys('curl -O ' .. url)
  sys('gunzip -f terminfo.src.gz')
  sys(('cat terminfo.src scripts/windows.ti | tic -x -o "%s" -'):format(db))
  sys('rm -f terminfo.src')
else
  print('using cached terminfo in ' .. db)
end

local function enumify(str)
  return 'kTerm_' .. str
end
local function quote(str)
  if str == nil then
    return 'NULL'
  end
  -- remungle the strings to look like C strings
  str = string.gsub(str, '\\E', '\\033')
  str = string.gsub(str, '%^G', '\\a')
  str = string.gsub(str, '%^H', '\\b')
  str = string.gsub(str, '%^O', '\\017') -- o dod
  -- str = string.gsub(str, "\\", "\\\\")
  str = string.gsub(str, '"', '\\"')
  return '"' .. str .. '"'
end

--- @type fun(...: any)
local dbg = function() end
-- dbg = print

local f_enum = assert(io.open(target_enum, 'wb'))
f_enum:write('// generated by src/gen/gen_terminfo.lua\n\n')
f_enum:write('#pragma once\n\n')
f_enum:write('typedef enum {\n')
for _, name in ipairs(wanted_strings) do
  f_enum:write('  ' .. enumify(name) .. ',\n')
end
f_enum:write('#define kTermExtOffset ' .. enumify(wanted_strings_ext[1][1]) .. '\n')
for _, item in ipairs(wanted_strings_ext) do
  f_enum:write('  ' .. enumify(item[1]) .. ',\n')
end
f_enum:write('  kTermCount,  // sentinel\n')
f_enum:write('} TerminfoDef;\n\n')

f_enum:write([[
// TODO(bfredl): physical F-keys beyond F12 are uncommon. But terminfo
// likes to represent chords with shift and/or ctrl and F keys as high
// F-key numbers. The same chords can also be recognized by driver-csi.c
// but will then be encoded as chords. We might actually prefer that but it is
// potentially breaking change.
]])
local func_key_max = terminfo.fields.func_key_max
f_enum:write('#define kTerminfoFuncKeyMax ' .. func_key_max .. '\n')
f_enum:write('typedef enum {\n')
for _, item in ipairs(wanted_termkeys) do
  f_enum:write('  kTermKey_' .. item[1] .. ',\n')
end
f_enum:write('  kTermKeyCount,\n')
f_enum:write('} TerminfoKey;\n')
f_enum:close()

local f_defs = assert(io.open(target_gen, 'wb'))

f_defs:write('// uncrustify:off\n\n')

local version = io.popen('infocmp -V'):read '*a'
f_defs:write('// Generated by src/gen/gen_terminfo.lua and ' .. version .. '\n')

f_defs:write('#pragma once\n\n')
f_defs:write('#include "nvim/tui/terminfo_defs.h"\n')

for _, entry in ipairs(entries) do
  local term, target = unpack(entry)
  local fil = io.popen('infocmp -L -x -1 -A ' .. db .. ' ' .. term):read '*a'
  local lines = vim.split(fil, '\n')
  local prepat = '^%s*([%w_]+)'
  local boolpat = prepat .. ','
  local numpat = prepat .. '#([^,]+),'
  local strpat = prepat .. '=([^,]+),'
  local bools = {} --- @type table<string, true>
  local nums = {} --- @type table<string, string>
  local strs = {} --- @type table<string, string>
  for i, line in ipairs(lines) do
    local boolmatch = string.match(line, boolpat)
    local nummatch, numval = string.match(line, numpat)
    local strmatch, strval = string.match(line, strpat)
    if boolmatch then
      dbg('boolean: ' .. boolmatch)
      bools[boolmatch] = true
    elseif nummatch then
      dbg('number: ' .. nummatch .. ' is ' .. numval)
      nums[nummatch] = numval
    elseif strmatch then
      dbg('string: ' .. strmatch .. ' is ' .. strval)
      strs[strmatch] = strval
    else
      dbg('UNKNOWN:', i, line)
    end
  end

  f_defs:write('\nstatic const TerminfoEntry ' .. target .. ' = {\n')
  for _, b in ipairs(wanted_bools) do
    f_defs:write('  .' .. b .. ' = ' .. tostring(bools[b] or false) .. ',\n')
  end

  for _, name in ipairs(wanted_ints) do
    f_defs:write('  .' .. name .. ' = ' .. (nums[name] or '-1') .. ',\n')
  end
  f_defs:write('  .defs = {\n')
  for _, name in ipairs(wanted_strings) do
    f_defs:write('    [' .. enumify(name) .. '] = ' .. quote(strs[name]) .. ',\n')
  end
  for _, item in ipairs(wanted_strings_ext) do
    f_defs:write('    [' .. enumify(item[1]) .. '] = ' .. quote(strs[item[2]]) .. ',\n')
  end
  f_defs:write('  },\n')
  f_defs:write('  .keys = {\n')
  for _, item in ipairs(wanted_termkeys) do
    local name = item[1]
    f_defs:write(
      '    [kTermKey_'
        .. name
        .. '] = {'
        .. quote(strs['key_' .. name])
        .. ', '
        .. quote(strs['key_s' .. name])
        .. '},\n'
    )
  end
  f_defs:write('  },\n')
  f_defs:write('  .f_keys = {\n')
  if strs['key_f1'] == nil then
    f_defs:write('    NULL,\n') -- compiler get sad if list is empty
  else
    f_defs:write('    // note: offset by one, f_keys[0] is F1 and so on\n')
  end
  for i = 1, func_key_max do
    if strs['key_f' .. i] ~= nil then
      f_defs:write('    [' .. i - 1 .. '] = ' .. quote(strs['key_f' .. i]) .. ',\n')
    end
  end
  f_defs:write('  },\n')

  f_defs:write('};\n')
end

f_defs:write('\n#define XLIST_TERMINFO_BOOLS \\\n')
for _, item in ipairs(wanted_bools) do
  f_defs:write('  X(' .. item .. ') \\\n')
end
f_defs:write('// end of list\n\n')
f_defs:write('#define XLIST_TERMINFO_INTS \\\n')
for _, item in ipairs(wanted_ints) do
  f_defs:write('  X(' .. item .. ') \\\n')
end
f_defs:write('// end of list\n\n')
f_defs:write('#define XLIST_TERMINFO_BUILTIN \\\n')
for _, name in ipairs(wanted_strings) do
  f_defs:write('  X(' .. name .. ') \\\n')
end
f_defs:write('// end of list\n\n')
f_defs:write('#define XLIST_TERMINFO_EXT \\\n')
for _, item in ipairs(wanted_strings_ext) do
  f_defs:write('  X(' .. item[1] .. ', ' .. item[2] .. ') \\\n')
end
f_defs:write('// end of list\n\n')
f_defs:write('#define XYLIST_TERMINFO_KEYS \\\n')
for _, item in ipairs(wanted_termkeys) do
  f_defs:write('  ' .. (item[2] and 'Y' or 'X') .. '(' .. item[1] .. ') \\\n')
end
f_defs:write('// end of list\n\n')
f_defs:write('#define XLIST_TERMINFO_FKEYS \\\n')
for i = 1, func_key_max do
  f_defs:write('  X(f' .. i .. ', ' .. i - 1 .. ') \\\n')
end
f_defs:write('// end of list\n')
f_defs:close()