-- Fullwidth to halfwidth - 全角转半角
-- 把全角的字母、数字转为半角字符，符号也转为常见的符号
-- Copyright (c) 2019, mixj93 <mixj93@163.com>

local tr = aegisub.gettext

script_name = tr("Fullwidth to halfwidth - 全角转半角")
script_description = tr("把全角的字母、数字转为半角字符，符号也转为常见的符号")
  script_author = "mixj93"
  script_version = "1"

include("unicode.lua")

lookup = {
  ['１'] = '1', ['２'] = '2', ['３'] = '3', ['４'] = '4', 
	['５'] = '5', ['６'] = '6', ['７'] = '7', ['８'] = '8', 
  ['９'] = '9', ['０'] = '0',
  ['Ａ'] = 'A', ['Ｂ'] = 'B', ['Ｃ'] = 'C', ['Ｄ'] = 'D', 
	['Ｅ'] = 'E', ['Ｆ'] = 'F', ['Ｇ'] = 'G', ['Ｈ'] = 'H', 
	['Ｉ'] = 'I', ['Ｊ'] = 'J', ['Ｋ'] = 'K', ['Ｌ'] = 'L', 
	['Ｍ'] = 'M', ['Ｎ'] = 'N', ['Ｏ'] = 'O', ['Ｐ'] = 'P', 
	['Ｑ'] = 'Q', ['Ｒ'] = 'R', ['Ｓ'] = 'S', ['Ｔ'] = 'T', 
	['Ｕ'] = 'U', ['Ｖ'] = 'V', ['Ｗ'] = 'W', ['Ｘ'] = 'X', 
	['Ｙ'] = 'Y', ['Ｚ'] = 'Z',
	['ａ'] = 'a', ['ｂ'] = 'b', ['ｃ'] = 'c', ['ｄ'] = 'd', 
	['ｅ'] = 'e', ['ｆ'] = 'f', ['ｇ'] = 'g', ['ｈ'] = 'h', 
	['ｉ'] = 'i', ['ｊ'] = 'j', ['ｋ'] = 'k', ['ｌ'] = 'l', 
	['ｍ'] = 'm', ['ｎ'] = 'n', ['ｏ'] = 'o', ['ｐ'] = 'p', 
	['ｑ'] = 'q', ['ｒ'] = 'r', ['ｓ'] = 's', ['ｔ'] = 't', 
	['ｕ'] = 'u', ['ｖ'] = 'v', ['ｗ'] = 'w', ['ｘ'] = 'x', 
	['ｙ'] = 'y', ['ｚ'] = 'z',
  ['－'] = '-', ['‥'] = '…', ['＂'] = '"'
}

function transform(subtitles, selected_lines, active_line)
	for z, i in ipairs(selected_lines) do
		local l = subtitles[i]
		
		aegisub.debug.out(string.format('Processing line %d: "%s"\n', i, l.text))
		aegisub.debug.out("Chars: \n")
		
		local in_tags = false
		local newtext = ""
		for c in unicode.chars(l.text) do
			aegisub.debug.out(5, c .. ' -> ')
			if c == "{" then
				in_tags = true
			end
			if in_tags then
				aegisub.debug.out(5, c .. " (ignored, in tags)\n")
				newtext = newtext .. c
			else
				if lookup[c] then
					aegisub.debug.out(5, lookup[c] .. " (converted)\n")
					newtext = newtext .. lookup[c]
				else
					aegisub.debug.out(5, c .. " (not found in lookup)\n")
					newtext = newtext .. c
				end
			end
			if c == "}" then
				in_tags = false
			end
		end
		
		l.text = newtext
		subtitles[i] = l
	end
	aegisub.set_undo_point(tr"Fullwidth to halfwidth - 全角转半角")
end

aegisub.register_macro(tr"Fullwidth to halfwidth - 全角转半角", tr"把全角的字母、数字转为半角字符，符号也转为常见的符号", transform)