using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

namespace OpenNest.Posts.Cincinnati
{
    public sealed class CincinnatiPostProcessor : IPostProcessor
    {
        public string Name => "Cincinnati CL-707";
        public string Author => "OpenNest";
        public string Description => "Cincinnati CL-707/CL-800/CL-900/CL-940/CLX family";

        public CincinnatiPostConfig Config { get; }

        public CincinnatiPostProcessor(CincinnatiPostConfig config)
        {
            Config = config;
        }

        public void Post(Nest nest, Stream outputStream)
        {
            // 1. Create variable manager and register standard variables
            var vars = CreateVariableManager();

            // 2. Filter to non-empty plates
            var plates = nest.Plates
                .Where(p => p.Parts.Count > 0)
                .ToList();

            // 3. Create writers
            var preamble = new CincinnatiPreambleWriter(Config);
            var sheetWriter = new CincinnatiSheetWriter(Config, vars);

            // 4. Build material description from first plate
            var material = plates.FirstOrDefault()?.Material;
            var materialDesc = material != null
                ? $"{material.Name}{(string.IsNullOrEmpty(material.Grade) ? "" : $", {material.Grade}")}"
                : "";

            // 5. Write to stream
            using var writer = new StreamWriter(outputStream, Encoding.UTF8, 1024, leaveOpen: true);

            // Main program
            preamble.WriteMainProgram(writer, nest.Name ?? "NEST", materialDesc, plates.Count);

            // Variable declaration subprogram
            preamble.WriteVariableDeclaration(writer, vars);

            // Sheet subprograms
            for (var i = 0; i < plates.Count; i++)
            {
                var sheetIndex = i + 1;
                var subNumber = Config.SheetSubprogramStart + i;
                sheetWriter.Write(writer, plates[i], nest.Name ?? "NEST", sheetIndex, subNumber);
            }

            writer.Flush();
        }

        public void Post(Nest nest, string outputFile)
        {
            using var fs = new FileStream(outputFile, FileMode.Create, FileAccess.Write);
            Post(nest, fs);
        }

        private ProgramVariableManager CreateVariableManager()
        {
            var vars = new ProgramVariableManager();
            vars.GetOrCreate("ProcessFeedrate", 148);  // Set by G89, no expression
            vars.GetOrCreate("LeadInFeedrate", 126, $"[#148*{Config.LeadInFeedratePercent}]");
            vars.GetOrCreate("LeadInArcLine2Feedrate", 127, $"[#148*{Config.LeadInArcLine2FeedratePercent}]");
            vars.GetOrCreate("CircleFeedrate", 128, Config.CircleFeedrateMultiplier.ToString("0.#"));
            return vars;
        }
    }
}