// -------------------- Global Variables

// Helper Objects
var fs = new ActiveXObject("Scripting.FileSystemObject");
var st = DOpus.Create.StringTools();

// Default example for the mapDirToBrowser setting.
var map_dir_to_browser = {
	"D:\\Bookmarks\\Other\\": "C:\\Bin\\Browser.exe",
};

// Columns' Definitions
var config = {
	columns: [
		{
		name: "ToAddress",
		displayName: "To Address",
		target: "mail",
		re: /^To:\s(.*)$/,
		type: "string",
		defwidth: 18
		}, {
		name: "FromAddress",
		displayName: "From Address",
		target: "mail",
		re: /^From:\s(.*)$/,
		type: "string",
		defwidth: 18
		}, {
		name: "Subject",
		displayName: "Subject",
		target: "mail",
		re: /^Subject:\s(.*)$/,
		type: "string",
		defwidth: 20
		}, {
		name: "Newsgroups",
		displayName: "Newsgroups",
		target: "mail",
		re: /^Newsgroups:\s(.*)$/,
		type: "string",
		defwidth: 18
		}, {
		name: "Message-ID",
		displayName: "Message-ID",
		target: "mail",
		re: /^Message-ID:\s(.*)$/,
		type: "string",
		defwidth: 18
		}, {
		name: "Date",
		displayName: "Date",
		target: "mail",
		re: /^Date:\s(.*)$/,
		type: "datetime",
		defwidth: 10
		}, {
		name: "Webpage Address",
		displayName: "Address",
		target: "webpage",
		re: /^Content-Location:\s(.*)$/,
		type: "string",
		defwidth: 18
		}, {
		name: "Webpage Domain",
		displayName: "Domain",
		target: "webpage",
		re: /^Content-Location:\s(?:http)s?:\/\/(?:www\.)?(.*?)\/.*$/,
		type: "string",
		defwidth: 18
		}, {
		name: "Webpage Source",
		displayName: "Source",
		target: "webpage",
		re: /^From:\s(.*)$/,
		type: "string",
		defwidth: 18
		}, {
		name: "Webpage Subject",
		displayName: "Title",
		target: "webpage",
		re: /^Subject:\s(.*)$/,
		type: "string",
		defwidth: 20
		}, {
		name: "Webpage Date",
		displayName: "Visualized On",
		target: "webpage",
		re: /^Date:\s(.*)$/,
		type: "datetime",
		defwidth: 10
		}
	]
};

// -------------------- Event

// Called by Directory Opus to initialize the script.
function OnInit(initData) {
	var uid = "";
	var url = "";
	initData.url = url;
	initData.name = "Columns for Electronic Mail Format";
	initData.desc = "Columns for displaying e-mail header properties for e-mail and webpage files.";
	initData.copyright = "Initiated by wowbagger; With contributions from many fellow users; Fork maintened by AndersonNNunes.org";
	initData.version = "1.0";
	initData.default_enable = true;
	initData.min_version = "12.0";
	
	// Create a new ScriptCommand object and initialize it to add the command to Opus.
	var showPreviewCmd = initData.AddCommand();
	showPreviewCmd.name = "OpenWebpage";
	showPreviewCmd.method = "OnOpenWebpage";
	showPreviewCmd.desc = "Open webpage files.";
	showPreviewCmd.label = "Open Webpage";
	showPreviewCmd.template = "MULTI/S,REMOTE/S";
	
	// Helper Function
	// Easy way to determine settings.
	// Thanks goes to "tbone".
	// https://resource.dopus.com/t/helper-confighelper-easier-config-item-handling/19129
	function ConfigHelper(data) {
		var t=this; t.d=data; t.c=data.config; t.cd=DOpus.Create.Map();
		t.add=function(name, val, des){ t.l={n:name,ln:name.
			toLowerCase()}; return t.val(val).des(des);}
		t.des=function(des){ if (!des) return t; if (t.cd.empty)
			t.d.config_desc=t.cd; t.cd(t.l.n)=des; return t;}
		t.val=function(val){ var l=t.l; if (l.v!==l.x&&typeof l.v=="object")
			l.v.push_back(val);else l.v=t.c[l.n]=val;return t;}
		t.trn=function(){return t.des(t("script.config."+t.l.ln));}
	}
	
	// Helper object.
	var cfg = new ConfigHelper(initData);
	
	// Configuration.
	cfg.add("verbose", true, "Enable output of informative log? If set to false, only errors will print messages.");
	cfg.add("facilitateSubjectGrouping", true, "When enabled, grouping by subject ignores certain prefixes so that all messages from a thread are grouped together.");
	cfg.add("prefixRegExp", "(RES|ENC|Re|Fwd): ", "RegExp used to identify the prefixes to be ignored if the user enabled the 'facilitateSubjectGrouping' option.");
	cfg.add("clearOutput", false, "Clear output on run?");
	cfg.add("mapDirToBrowser", JSON.stringify(map_dir_to_browser, undefined, 2).replace(/(\n)+/g,"\r\n"), "Specifies which directories have files that should be opened with a given browser. More specific paths should be at the top.");
	
	// Temporary variables used to process the script configuration.
	var labelPrefix;
	
	for (i = 0; i < config.columns.length; i++) {
		
		// Determine the prefix from the target of the column.
		if (config.columns[i].target == "mail") {
			labelPrefix = "(Mail) ";
		} else if (config.columns[i].target == "webpage") {
			labelPrefix = "(Webpage) ";
		}
		
		AddNewColumn(initData, config.columns[i].name, config.columns[i].displayName, labelPrefix, config.columns[i].type, config.columns[i].defwidth);
	}
}

function OnOpenWebpage(scriptCmdData) {
	if (Script.config.clearOutput) {
		DOpus.ClearOutput();
	}
	
	// Check premisses.
	if (scriptCmdData.func.sourcetab.selected_files.count == 0)
	{
		error("No files are selected.");
		return;
	}
	
	if (scriptCmdData.func.sourcetab.selected_files.count > 1 && !scriptCmdData.func.args.got_arg.multi) {
		error("Too many files are selected. Use the MULTI switch if you really want the command to operate on multiple files.");
		return;
	}
	else
	{
		var multi = true;
	}
	
	// Adjust command behavior.
	var cmd = scriptCmdData.func.command;
	cmd.AddLine("// This line prevents an error when the Run method is executed before the the AddLine method being called at least once.");
	cmd.deselect = true;
	cmd.SetQualifiers("none");
	cmd.ClearFiles();
	
	if (multi == true) {
		// Filter selected files to consider only appropriate files.
		for (var eSel = new Enumerator(scriptCmdData.func.sourcetab.selected_files); !eSel.atEnd(); eSel.moveNext())
		{
			var selectedItem = eSel.item();
			for (var i = 0; i < selectedItem.groups.length; i++){
				if (selectedItem.groups(i).display_name == "Webpages")
				{
					cmd.AddFile(selectedItem);
				}
			}
		}
	} else {
		cmd.AddFile(scriptCmdData.func.sourcetab.selected_files(0));
	}
	
	for (var file_count = cmd.files.count - 1; file_count >= 0; file_count--)
	{
		var current_item = cmd.files(file_count);
		var current_item_path = String(current_item.realpath);
		
		if (scriptCmdData.func.args.got_arg.remote) {
			var item_id = encodeURIComponent("_CEMF_" + current_item_path);
			if (DOpus.Vars.Exists(item_id)) {
				var item = JSON.parse(DOpus.Vars.Get(item_id));
				var target_uri = item["Webpage Address"];
			} else {
				error("Metadata not cached for \"" + current_item.name + "\".");
				return;
			}
		} else {
			var target_uri = current_item_path;
		}
		
		var browser = "default";
		map_dir_to_browser = JSON.parse(Script.config.mapDirToBrowser);
		for (key in map_dir_to_browser) {
			if (DOpus.FSUtil.ComparePath(current_item_path, key, "cp")) {
				browser = map_dir_to_browser[key];
				break;
			}
		}
		
		if (browser === "default") {
			var open_browser_command = quotePath(target_uri);
		} else {
			var open_browser_command = quotePath(browser) + " " + quotePath(target_uri);
		}
		
		// Execute command line.
		var wsh = new ActiveXObject("WScript.Shell");
		var run_return_code = wsh.Run(open_browser_command, 1);
	}
}

// Helper Function
// Add column.
function AddNewColumn(initData, name, label, labelPrefix, type, defwidth) {
	var col;
	col = initData.AddColumn();
	col.name = name;
	col.label = labelPrefix + label;
	col.header = label;
	col.type = type;
	col.method = "OnValueRequest";
	if (name == "Subject" || name == "Webpage Subject") {
		col.autogroup = false;
	} else {
		col.autogroup = true;
	}
	col.autorefresh = true;
	col.justify = "left";
	col.multicol = true;
	col.keyscroll = true;
	if (defwidth != null && defwidth != 0) {
		col.defwidth = defwidth;
	}
}

// Helper Function
// Generate values for columns.
function OnValueRequest(scriptColData) {
	// Check that the target item really exists (sometimes it may be on a collection but may have been deleted already).
	if (!DOpus.FSUtil.Exists(scriptColData.item) || (!scriptColData.item.is_dir && !fs.FileExists(scriptColData.item.realpath)) || (scriptColData.item.is_dir && !fs.FolderExists(scriptColData.item.realpath))) {
		// error("Unable to locate \"" + scriptColData.item.realpath + "\".");
		return;
	}
	
	if (String(scriptColData.item.realpath).length > 259) {
		print("Path length is too long for the file \"" + scriptColData.item.realpath + "\". It has been ignored.");
		return;
	}
	
	if (!inArray(scriptColData.col, config.columns)) return;
	if (scriptColData.item.is_dir) return;
	if (isFromGroup(scriptColData.item, "Electronic Mail") || isFromGroup(scriptColData.item, "Webpages"))
	{
		// Check the cache first.
		var item_id = encodeURIComponent("_CEMF_" + scriptColData.item.realpath);
		if (DOpus.Vars.Exists(item_id)) {
			var item = JSON.parse(DOpus.Vars.Get(item_id));
			if (item["Cache Date"] !== String(scriptColData.item.modify)) {
				item = null;
				print("Cached data is stale and will be discarded.");
			}
			print("Using 'DOpus.Vars' cache.");
		}
		
		if (!item) {
			print("Data not found in the cache. Probing...");
			var item = ScanFile(scriptColData.item);
			item["Cache Date"] = String(scriptColData.item.modify);
			DOpus.Vars.Set(item_id, JSON.stringify(item, undefined, 4).replace(/(\n)+/g,"\r\n"));
		}
		
		if (item) {
			// Temporary variable that holds a value to be assigned to a column.
			var iValue;
			
			// Iterate over columns and assign values.
			for (i = 0; i < config.columns.length; i++) {
				
				if (!scriptColData.columns.exists(config.columns[i].name)) {
					continue;
				}
				
				iValue = item[config.columns[i].name];
				
				if (iValue == null) {
					continue;
				}
				
				// Handle column of type "datetime".
				if (config.columns[i].type == "datetime") {
					iValue = new Date(Date.parse(iValue)).getVarDate();
				} // Handle other types of column.
				else {
					// For the "Subject" column, remove common prefixes of the group value, if the user desires that.
					if (config.columns[i].name == "Subject" || config.columns[i].name == "Webpage Subject") {
						if (Script.config.facilitateSubjectGrouping) {
							scriptColData.columns(config.columns[i].name).group = iValue.replace(new RegExp(Script.config.prefixRegExp, "gi"), "")
						}
					}
				}
				
				// Assign computed value.
				scriptColData.columns(config.columns[i].name).value = iValue;
			}
		}
	}
}

// Helper Function
// Extract values from file.
function ScanFile(item, target) {
	var result = {};
	
	for (i = 0; i < config.columns.length; i++)
	{
		// Check premisses; skip column if check fail.
		if (isFromGroup(item, "Electronic Mail") && config.columns[i].target == "webpage") {
			continue;
		}
		if (isFromGroup(item, "Webpages") && config.columns[i].target == "mail") {
			continue;
		}
		
		// Open file in read mode.
		var fn = fs.OpenTextFile(item.realpath, 1);
		while (!fn.AtEndOfStream)
		{
			var textLine = fn.ReadLine();
			var match = config.columns[i].re.exec(textLine);
			if (match != null)
			{
				var found_content = match[1];
				var subsequentLine = fn.ReadLine();
				while (subsequentLine.match(/^(\s|\t).*$/)) {
					found_content += subsequentLine;
					subsequentLine = fn.ReadLine();
				}
				
				result[config.columns[i].name] = decode(found_content);
				fn.Close();
				break;
			}
		result[config.columns[i].name] = "";
		}
		fn.Close();
	}
	
	if (result)
		return result;
	else
		return null;
}

// Helper Function
// Check that a given item is present in an array.
function inArray(item, arr) {
	for (var i = 0; i < arr.length; i++) {
		if (item == arr[i].name) return true;
	}
}

// Helper Function
// Decode line of text.
function decode(text) {
	var encoded_multipart_regex_pattern = /\?=\s?\t?(=\?([^?]+)\?([^?]+)\?)/g;
	text = text.replace(encoded_multipart_regex_pattern, "")
	
	var encoded_part_regex_pattern = /(=\?([^?]+)\?([^?]+)\?)([^?]+)\?=/;
	var match_result = encoded_part_regex_pattern.exec(text);
	if (match_result != null) {
		var front = middle = back = "";
		var firstIndex = match_result.index;
		var lastIndex = encoded_part_regex_pattern.lastIndex;
		encoding_prefix = match_result[1];
		
		if (firstIndex !== 0) {
			front = text.slice(0, firstIndex);
		}
		
		try {
			middle = st.Decode(match_result[0].slice(0, -2), "auto");
		}
		catch (err) {
			if (Script.config.verbose) {
				return "[Unsupported Encoding]";
			} else {
				return "";
			}
		}
		
		if (lastIndex !== text.length - 1) {
			back = text.slice(lastIndex);
		}
		
		return String(front + middle + back);
	}
	
	return text;
}

// Helper Function
// Print only if requested.
function print(text) {
	if (Script.config.verbose) {
		DOpus.Output(text);
	}
}

// Helper Function
// Display error message.
function error(text) {
	DOpus.Output(text, true);
}

// Helper Function
// Return true if 'item' is from file type group 'needle'.
function isFromGroup(item, needle) {
	if (item.groups.length) {
		for (var i = 0; i < item.groups.length; i++) {
			if (item.groups(i).display_name === needle) return true;
		}
	}
	return false;
}

// Helper Function
// Return string value path with quotes if all is true or if the path contains a space.
// Thanks goes to "spiralx".
// https://resource.dopus.com/t/scripts-js-snippet-collection-functions-and-helpers/18387
function quotePath(path, all) {
	path = String(path);
	if ((path.indexOf('"') === 0) && (path.lastIndexOf('"') === path.length - 1)) {
		return path;
	} else {
		all = typeof all === "boolean" ? all : false;
		return all || path.indexOf(' ') !== -1 ? ('"' + path + '"') : path;
	}
}