--- 常用工具类接口
-- @module utils
-- @author 小强,稀饭放姜
-- @license MIT
-- @copyright openLuat.com
-- @release 2017.10.19
module(..., package.seeall)

--- 字符转16进制,如"123abc"转为"313233616263"
-- @param str 输入字符串
-- @return hexstring 16进制组成的串
-- @return len 输入的字符串长度
-- @usage
-- string.tohex("\1\2\3") -> "010203" 3
-- string.tohex("123abc") -> "313233616263" 6
function string.tohex(str)
    return str:gsub('.', function(c)
        return string.format("%02X", string.byte(c))
    end)
end
--- 16进制转字符，如"313233616263"转为"123abc", 函数里加入了过滤分隔符，可以过滤掉大部分分隔符（可参见正则表达式中\s和\p的范围）。
-- @string hex,16进制组成的串
-- @return charstring,字符组成的串
-- @return len,输出字符串的长度
-- @usage
-- string.fromhex("010203")       ->  "\1\2\3"
-- string.fromhex("313233616263:) ->  "123abc"
function string.fromhex(hex)
    --滤掉分隔符
    local hex = hex:gsub("[%s%p]", ""):upper()
    return hex:gsub("%x%x", function(c)
        return string.char(tonumber(c, 16))
    end)
end
--- 返回utf8编码字符串的长度
-- @string str,utf8编码的字符串,支持中文
-- @return number,返回字符串长度
-- @usage local cnt = string.utf8len("中国"),str = 2
function string.utf8len(str)
    local len = #str
    local left = len
    local cnt = 0
    local arr = {0, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc}
    while left ~= 0 do
        local tmp = string.byte(str, -left)
        local i = #arr
        while arr[i] do
            if tmp >= arr[i] then
                left = left - i
                break
            end
            i = i - 1
        end
        cnt = cnt + 1
    end
    return cnt
end
-- 将一个字符转为urlencode编码
local function urlencodeChar(c)
    return "%" .. string.format("%02X", string.byte(c))
end
--- 返回字符串的urlencode编码
-- @string str，要转换编码的字符串
-- @return str,urlencode编码的字符串
-- @usage string.urlencode("####133")
function string.urlencode(str)
    return string.gsub(string.gsub(string.gsub(tostring(str), "\n", "\r\n"), "([^%w%.%- ])", urlencodeChar), " ", "+")
end
--- 返回数字的千位符号格式
-- @number num,数字
-- @return string，千位符号的数字字符串
-- @usage loca s = string.formatNumberThousands(1000) ,s = "1,000"
function string.formatNumberThousands(num)
    local k, formatted
    formatted = tostring(tonumber(num))
    while true do
        formatted, k = string.gsub(formatted, "^(-?%d+)(%d%d%d)", '%1,%2')
        if k == 0 then break end
    end
    return formatted
end
--- 判断文件是否存在
-- @string path,文件全名例如："/ldata/call.mp3"
-- @return boole,存在为true,不存在为false
-- @usage local ex = io.exists("/ldata/call.mp3")
function io.exists(path)
    local file = io.open(path, "r")
    if file then
        io.close(file)
        return true
    end
    return false
end
--- 读取文件并返回文件的内容
-- @string path,文件全名例如："/ldata/call.txt"
-- @return string,文件的内容,文件不存在返回nil
-- @usage local c = io.readfile("/ldata/call.txt")
function io.readfile(path)
    local file = io.open(path, "r")
    if file then
        local content = file:read("*a")
        io.close(file)
        return content
    end
    return nil
end
--- 写入文件指定的内容,默认为覆盖二进制模式
-- @string path,文件全名例如："/ldata/call.txt"
-- @string content,文件内容
-- @string mode,文件写入模式默认"w+b"
-- @return string,文件的内容
-- @usage local c = io.writefile("/ldata/call.txt","test")
function io.writefile(path, content, mode)
    local mode = mode or "w+b"
    local file = io.open(path, mode)
    if file then
        if file:write(content) == nil then return false end
        io.close(file)
        return true
    else
        return false
    end
end
--- 将文件路径分解为table信息
-- @string path,文件路径全名例如:"/ldata/call.txt"
-- @return table,{dirname="/ldata/",filename="call.txt",basename="call",extname=".txt"}
-- @usage loca p = io.pathinfo("/ldata/call.txt")
function io.pathinfo(path)
    local pos = string.len(path)
    local extpos = pos + 1
    while pos > 0 do
        local b = string.byte(path, pos)
        if b == 46 then -- 46 = char "."
            extpos = pos
        elseif b == 47 then -- 47 = char "/"
            break
        end
        pos = pos - 1
    end
    
    local dirname = string.sub(path, 1, pos)
    local filename = string.sub(path, pos + 1)
    extpos = extpos - pos
    local basename = string.sub(filename, 1, extpos - 1)
    local extname = string.sub(filename, extpos)
    return {
        dirname = dirname,
        filename = filename,
        basename = basename,
        extname = extname
    }
end
--- 返回文件大小
-- @string path,文件路径全名例如:"/ldata/call.txt","test"
-- @return number ,文件大小
-- @usage locan cnt = io.filesize("/ldata/call.txt")
function io.filesize(path)
    local size = 0
    local file = io.open(path, "r")
    if file then
        local current = file:seek()
        size = file:seek("end")
        file:seek("set", current)
        io.close(file)
    end
    return size
end