Logger

--[[
    logger by darraghd493

    A logger that logs messages with a custom format and placeholders.
    This is useful for logging messages to the console with a custom format.

    Core placeholders:
    %name%: The name of the logger
    %level%: The level of the logger
    %message%: The message to log
    %time%: The current time in HH:MM:SS format
]]

local Logger = {
    name = "Logger";
    format = "[%level%] [%name%] %time%: %message%";
    placeholders = { -- Custom placeholders, optional
        time = function()
            return os.date("%H:%M:%S")
        end;
    },
    levels = {
        DEBUG = 0;
        INFO = 1;
        WARN = 2;
        ERROR = 3;
    };
    minimum = 1;

    -- Internal properties
    history = {};
}
Logger.__index = Logger

local function fetchLevel(level: number)
    for name, value in pairs(Logger.levels) do
        if value == level then
            return name
        end
    end
    return "UNKNOWN"
end

function Logger.new(name: string, format: string, placeholders: table, minimum: number)
    local self = setmetatable({
        name = name;
        format = format;
        minimum = minimum or Logger.levels.INFO;
        history = {};
    }, Logger)
    if placeholders ~= nil then
        for placeholder, value in pairs(placeholders) do
            self.placeholders[placeholder] = value
        end
    end
    return self
end

function Logger:log(message: string, level: number)
    level = level or self.levels.INFO

    local formatted = self.format
    for placeholder, value in pairs(self.placeholders) do
        formatted = formatted:gsub("%%" .. placeholder .. "%%", value)
    end
    formatted = formatted:gsub("%%level%%", fetchLevel(level))
    formatted = formatted:gsub("%%name%%", self.name)
    formatted = formatted:gsub("%%message%%", message)

    if level < self.minimum then
        return
    end

    if level == self.levels.DEBUG or level == self.levels.INFO then
        print(formatted)
    elseif level == self.levels.WARN then
        warn(formatted)
    elseif level == self.levels.ERROR then
        error(formatted)
    end

    self:push(formatted)
end

function Logger:debug(message: string)
    self:log(message, self.levels.DEBUG)
end

function Logger:info(message: string)
    self:log(message, self.levels.INFO)
end

function Logger:warn(message: string)
    self:log(message, self.levels.WARN)
end

function Logger:error(message: string)
    self:log(message, self.levels.ERROR)
end

function Logger:push(message: string, level)
    table.insert(self.history, {
        message = message;
        level = level or self.levels.INFO;
    })
end

function Logger:get(index: number)
    return self.history[index]
end

function Logger:remove(index: number)
    table.remove(self.history, index)
end

function Logger:clear()
    self.history = {}
end

function Logger:__tostring() -- Internal method
    local str = self.name .. " logger history (formatted):\n"
    for i, v in ipairs(self.history) do
        str = str .. v.message .. "\n"
    end
    return str
end

return Logger