/**
 * Copyright: Copyright (c) 2011 Jacob Carlborg. All rights reserved.
 * Authors: Jacob Carlborg
 * Version: Initial created: Jan 9, 2011
 * License: $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost Software License 1.0)
 */
module dvm.dvm.ShellScript;

import std.conv : text;
import std.exception : assumeUnique;
import std.format : format;

import tango.io.device.File;

class ShellScript
{
    string path;
    private string content_;

    string content ()
    {
        return content_;
    }

    private string content (string content)
    {
        return content_ = content;
    }

    this (string path = "")
    {
        this.path = path;
    }

    ShellScript allArgs (bool quote = true)
    {
        append(Sh.allArgs);
        return this;
    }

    ShellScript comment (string c)
    {
        append(Sh.comment(c));
        return this;
    }

    ShellScript declareVariable (string name, string value = "", bool local = false)
    {
        append(Sh.declareVariable(name, value, local)).nl;
        return this;
    }

    ShellScript echoOff ()
    {
        version (Windows)
            append(Sh.echoOff).nl;

        return this;
    }

    ShellScript exec (string name, string args = "")
    {
        append(Sh.exec(name, args));
        return this;
    }

    ShellScript export_ (string name, string content, bool quote = true)
    {
        append(Sh.export_(name, content, quote));
        return this;
    }

    ShellScript exportPath (string name, string[] args ...)
    {
        string content ;

        foreach (i, arg ; args)
        {
            if (i != args.length - 1)
                content ~= arg ~ Sh.separator;

            else
                content ~=  arg;
        }

        return export_(name, content);
    }

    ShellScript ifFileIsNotEmpty (string path, void delegate () ifBlock, void delegate () elseBlock = null)
    {
        version (Posix)
            ifStatement("-s " ~ path, ifBlock, elseBlock);

        else
            ifStatement("exist " ~ path, ifBlock, elseBlock);

        return this;
    }

    ShellScript ifStatement (string condition, void delegate () ifBlock, void delegate () elseBlock = null)
    {
        version (Posix)
        {
            append(format("if [ %s ] ; then", condition)).nl.indent;
            ifBlock();
            nl;

            if (elseBlock)
            {
                append("else").nl.indent;
                elseBlock();
                nl;
            }

            append("fi");
        }

        else
        {
            append(format("if %s (", condition)).nl.indent;
            ifBlock();
            nl;
            append(")");

            if (elseBlock)
            {
                append(" else (").nl.indent;
                elseBlock();
                nl;
                append(")");
            }
        }

        return this;
    }

    ShellScript printError (string message, bool singleQuote = false)
    {
        version (Posix)
        {
            auto quote = singleQuote ? "'" : `"`;
            append(format(`echo %sError: %s%s >&2`, quote, message, quote));
        }

        else
            append(format(`echo Error: %s >&2`, message));

        return this;
    }

    ShellScript shebang ()
    {
        version (Posix)
        {
            if (Sh.shebang != "")
                append(Sh.shebang).nl;
        }

        return this;
    }

    ShellScript source (string path)
    {
        append(Sh.source(path));
        return this;
    }

    ShellScript variable (string name, bool quote = true)
    {
        append(Sh.variable(name, quote));
        return this;
    }

    ShellScript write ()
    {
        File.set(path, content);
        return this;
    }

    ShellScript append(T)(T value)
    {
        content_ ~= value.text;
        return this;
    }


    ShellScript nl ()
    {
        version (Posix)
            append('\n');

        else
            append("\r\n");

        return this;
    }

    ShellScript indent ()
    {
        append('\t');
        return this;
    }
}

struct Sh
{
    static:

    string quote (string str)
    {
        return format(`"%s"`, str);
    }

    version (Posix)
    {
        enum shebang = "#!/bin/sh";
        enum separator = ":";

        string allArgs (bool quote = true)
        {
            return quote ? `"$@"` : "$@";
        }

        string comment (string c)
        {
            return "# " ~ c;
        }

        string declareVariable (string name, string value = "", bool local = false)
        {
            string loc = local ? "local " : "";

            if (value == "")
                return loc ~ name;

            return format("%s%s=%s", loc, name, value);
        }

        string exec (string name, string args = "")
        {
            args = args == "" ? "" : ' ' ~ args;

            return format("exec %s%s", name, args);
        }

        string export_ (string name, string value, bool quote = true)
        {
            return format("%s=\"%s\"\nexport %s", name, value, name);
        }

        string source (string path, bool quote = true)
        {
            return format(". %s", path);
        }

        string exec (string command)
        {
            return format("exec %s", command);
        }

        string variable (string name, bool quote = true)
        {
            return quote ? format(`"$%s"`, name) : '$' ~ name;
        }
    }

    else version (Windows)
    {
        // DMD 1.068 and up optimizes this out causing a linker error
        //enum shebang = "";
        enum echoOff = "@echo off";
        enum separator = ";";

        string allArgs (bool quote = true)
        {
            return "%*";
        }

        string comment (string c)
        {
            return "rem " ~ c;
        }

        string declareVariable (string name, string value = "", bool local = false)
        {
            return format("set %s=%s", name, value);
        }

        string export_ (string name, string content, bool quote = true)
        {
            return format("set %s=%s", name, content);
        }

        string source (string path)
        {
            return format("call %s", path);
        }

        string exec (string name, string args = "")
        {
            return format("%s %s", name, args);
        }

        string variable (string name, bool quote = true)
        {
            return quote ? format(`"%%s%"`, name) : '%' ~ name ~ '%';
        }
    }
}

string slashSafeSubstitute (string haystack, string needle, string replacement)
{
    import tango.text.Util;

    version (Windows)
    {
        needle = needle.substitute("/", "\\").assumeUnique;
        replacement = replacement.substitute("/", "\\").assumeUnique;
    }

    return haystack.substitute(needle, replacement).assumeUnique;
}