/*

 * Copyright (c) 2015, Jason Maltzen

 Permission is hereby granted, free of charge, to any person obtaining a copy

 of this software and associated documentation files (the "Software"), to deal

 in the Software without restriction, including without limitation the rights

 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 copies of the Software, and to permit persons to whom the Software is

 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in

 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 THE SOFTWARE.

*/

using System;

using System.IO;

using System.Collections.Generic;

using System.Collections.Concurrent;

using System.Text.RegularExpressions;

using System.Threading;

namespace DesertPaintLab

{

    public class NewRecipeEventArgs : EventArgs

    {

        string color;

        PaintRecipe recipe;

        public NewRecipeEventArgs(string color, PaintRecipe recipe)

        {

            this.color = color;

            this.recipe = recipe;

        }

        public string Color

        {

            get {

                return color;

            }

        }

        public PaintRecipe Recipe

        {

            get {

                return recipe;

            }

        }

    }

    public class RecipeGenerator

    {

        public enum SearchType {

            DEPTH_FIRST,

            BREADTH_FIRST

        };

        public SearchType Mode { get; set; }

        public uint MaxQuantity { get; private set; } // maximum number of total ingredients

        public uint MaxReagents { get; private set; } // maximum number of reagents to use in the recipe

        public uint MinReagents { get; private set; } // minimum number of reagents to use in the recipe

        public uint FullQuantityDepth { get; private set; } // at or equal this number of reagents, ignore ingredient settings for max quantity

        public uint FullQuantity { get; private set; }  // The max number of a reagent to use at full quantity

        ReactionSet reactions;

        bool running = false;

        int runningThreads = 0;

        SortedDictionary<string, uint> recipeCosts = new SortedDictionary<string, uint>();

        SortedDictionary<string, PaintRecipe> recipes = new SortedDictionary<string, PaintRecipe>();

        uint totalReagents;

        List<Reagent> costSortedReagents = new List<Reagent>();

        ConcurrentQueue<RecipeSearchNode> searchQueue = new ConcurrentQueue<RecipeSearchNode>();

        ulong recipeCount = 0;

        List<Thread> generatorThreads = new List<Thread>();

        Object workerLock = new Object();

        bool requestCancel = false;

        StreamWriter log;

        // events

        public event EventHandler Finished;

        public event EventHandler Progress;

        public event EventHandler<NewRecipeEventArgs> NewRecipe;

        public RecipeGenerator(ReactionSet reactions)

        {

            Mode = SearchType.BREADTH_FIRST;

            this.reactions = reactions;

            foreach (PaintColor color in Palette.Colors)

            {

                recipes.Add(color.Name, new PaintRecipe());

                recipeCosts.Add(color.Name, uint.MaxValue);

            }

            MinReagents = 1;

            MaxReagents = 5;

            MaxQuantity = 20;

        }

        public SortedDictionary<string, PaintRecipe> Recipes

        {

            get

            {

                return recipes;

            }

        }

        public ulong RecipeCount

        {

            get

            {

                return recipeCount;

            }

        }

        public bool CanResume

        {

            get

            {

                return (!running && (searchQueue.Count > 0));

            }

        }

        public string Log

        {

            set

            {

                if (value != null)

                {

                    log = new StreamWriter(value);

                }

                else

                {

                    log = null;

                }

            }

        }

        private class ReagentCostSort : IComparer<Reagent>

        {

            public int Compare(Reagent reagent1, Reagent reagent2)

            {

                return (int)reagent1.Cost - (int)reagent2.Cost;

            }

        }

        public void InitRecipes(SortedDictionary<string, PaintRecipe> initialRecipes)

        {

            if (running)

            {

                return;

            }

            foreach (PaintRecipe recipe in initialRecipes.Values)

            {

                //PaintRecipe recipeCopy = new PaintRecipe(recipe);

                AddCheapestRecipe(recipe);

            }

        }

        private void InitSortedReagents()

        {

            costSortedReagents.Clear();

            foreach (string name in ReagentManager.Names)

            {

                Reagent reagent = ReagentManager.GetReagent(name);

                costSortedReagents.Add(reagent);

            }

            costSortedReagents.Sort(new ReagentCostSort());

        }

        public void BeginRecipeGeneration(uint maxQuantity, uint minReagents, uint maxReagents, uint fullQuantityDepth, uint fullQuantity)

        {

            if (running)

            {

                // Already running - don't start again

                return;

            }

            this.MaxQuantity = maxQuantity;

            this.MinReagents = minReagents;

            this.MaxReagents = maxReagents;

            this.FullQuantity = fullQuantity;

            this.FullQuantityDepth = fullQuantityDepth;

            // first, sort reagents by cost.

            InitSortedReagents();

            totalReagents = (uint)costSortedReagents.Count;

            // Pre-populate recipes list with:

            // 1) 1-ingredient recipes @ 10db for all enabled ingredients with a count >= 10

            // 2) any previously-generated recipes

            int enabledReagentCount = 0;

            PaintRecipe recipe = new PaintRecipe();

            recipe.Reactions = reactions;

            foreach (Reagent reagent in costSortedReagents)

            {

                if (reagent.Enabled)

                {

                    if (!reagent.IsCatalyst && ((reagent.RecipeMax >= 10) || ((FullQuantityDepth > 0) && (FullQuantity >= 10))))

                    {

                        recipe.Clear();

                        recipe.AddReagent(reagent.Name, 10);

                        AddCheapestRecipe(recipe);

                    }

                    ++enabledReagentCount;

                }

            }

            this.MaxReagents = (uint)Math.Min(enabledReagentCount, this.MaxReagents);

            this.MinReagents = (uint)Math.Min(this.MinReagents, this.MaxReagents);

            while (!searchQueue.IsEmpty)

            {

                RecipeSearchNode node;

                searchQueue.TryDequeue(out node);

            }

            for (uint reagentIdx = 0; reagentIdx < costSortedReagents.Count; ++reagentIdx)

            {

                if (costSortedReagents[(int)reagentIdx].Enabled)

                {

                    RecipeSearchNode initialNode = new RecipeSearchNode(costSortedReagents, reagentIdx);

                    initialNode.FullQuantity = FullQuantity;

                    initialNode.FullQuantityDepth = FullQuantityDepth;

                    initialNode.MaxQuantity = maxQuantity;

                    initialNode.MinReagents = minReagents;

                    initialNode.MaxReagents = maxReagents;

                    searchQueue.Enqueue(initialNode);

                }

            }

            recipeCount = 0;

            if (log != null)

            {

                log.WriteLine("Begin recipe generation: MaxQuantity={0} MinReagents={1} MaxReagents={2} FullQuantity={3} FullQuantityDepth={4}", MaxQuantity, MinReagents, MaxReagents, FullQuantity, FullQuantityDepth);

            }

            // start worker threads to do the actual work

            ResumeRecipeGeneration();

        }

        public void ResumeRecipeGeneration()

        {

            if (running)

            {

                // Already running - don't start again

                return;

            }

            running = true;

            requestCancel = false;

            if (log != null)

            {

                log.WriteLine("Resuming recipe generation: pre-threads={0} reagent count={1} search queue={2}", runningThreads, costSortedReagents.Count, searchQueue.Count);

            }

            runningThreads = 0; // presumably!

            if (threadCount == 0)

            {

                if (Finished != null)

                {

                    Finished(this, null);

                }

            }

            generatorThreads.Clear();

            for (int i = 0; i < threadCount; ++i)

            {

                Thread thr = new Thread(new ThreadStart(this.Generate));

                generatorThreads.Add(thr);

            }

            foreach (Thread thr in generatorThreads)

            {

                thr.Start();

            }

        }

        public bool SaveState(string file)

        {

            if (running)

            {

                // can't save state while running

                return false;

            }

            using (StreamWriter writer = new StreamWriter(file, false))

            {

                writer.WriteLine("MinReagents: {0}", MinReagents);

                writer.WriteLine("MaxReagents: {0}", MaxReagents);

                writer.WriteLine("FullQuantityDepth: {0}", FullQuantityDepth);

                writer.WriteLine("FullQuantity: {0}", FullQuantity);

                writer.WriteLine("TotalReagents: {0}", totalReagents);

                writer.WriteLine("RecipeCount: {0}", recipeCount);

                writer.WriteLine("SearchType: {0}", Mode.ToString());

                foreach (KeyValuePair<string, PaintRecipe> pair in recipes)

                {

                    PaintRecipe recipe = pair.Value;

                    string colorName = Palette.FindNearest(recipe.ReactedColor);

                    writer.WriteLine("BeginRecipe: {0}", colorName);

                    foreach (PaintRecipe.RecipeIngredient ingredient in recipe.Ingredients)

                    {

                        writer.WriteLine("Ingredient: {0}={1}", ingredient.name, ingredient.quantity);

                    }

                    writer.WriteLine("EndRecipe: {0}", colorName);

                }

                writer.WriteLine("SearchNodes: {0}", searchQueue.Count);

                foreach (RecipeSearchNode node in searchQueue)

                {

                    node.SaveState(writer);

               }

            }

            return true;

        }

        static Regex keyValueRegex = new Regex(@"(?<key>\w+)\:\s*(?<value>.+)\s*");

        static Regex ingredientRegex = new Regex(@"(?<ingredient>(\w+\s)*\w+)\s*=\s*(?<quantity>\d)\s*");

        public bool LoadState(string file)

        {

            // cannot be running, and reactions must be set

            if (running)

            {

                return false;

            }

            InitSortedReagents();

            bool success = true;

            PaintRecipe currentRecipe = null;

            Match match;

            string line;

            using (StreamReader reader = new StreamReader(file, false))

            {

                while (success && ((line = reader.ReadLine()) != null))

                {

                    match = keyValueRegex.Match(line);

                    if (match.Success)

                    {

                        string value = match.Groups["value"].Value;

                        switch(match.Groups["key"].Value)

                        {

                            case "MinReagents":

                                MinReagents = uint.Parse(value);

                                MaxReagents = (uint)Math.Max(this.MinReagents, this.MaxReagents);

                                break;

                            case "MaxReagents":

                                MaxReagents = uint.Parse(value);

                                MinReagents = (uint)Math.Min(this.MinReagents, this.MaxReagents);

                                break;

                            case "FullQuantityDepth":

                                FullQuantityDepth = uint.Parse(value);

                                break;

                            case "FullQuantity":

                                FullQuantity = uint.Parse(value);

                                break;

                            case "TotalReagents":

                                totalReagents = uint.Parse(value);

                                break;

                            case "RecipeCount":

                                if (!ulong.TryParse(value, out recipeCount))

                                {

                                    // must have rolled to negative - try as an int and convert

                                    int recipeCountInt = int.Parse(value);

                                    recipeCount = (ulong)((long)recipeCountInt & 0x00000000ffffffffL);

                                }

                                break;

                            case "BeginRecipe":

                                currentRecipe = new PaintRecipe();

                                currentRecipe.Reactions = reactions;

                                break;

                            case "EndRecipe":

                                if (currentRecipe != null)

                                {

                                    PaintColor color = currentRecipe.ReactedColor;

                                    uint cost = currentRecipe.Cost;

                                    recipes[color.Name] = currentRecipe; // replace

                                    recipeCosts[color.Name] = cost;

                                    currentRecipe = null;

                                }

                                break;

                            case "Ingredient":

                                if (currentRecipe != null)

                                {

                                    Match ingredientMatch = ingredientRegex.Match(match.Groups["value"].Value);

                                    if (ingredientMatch.Success)

                                    {

                                        uint quantity = uint.Parse(ingredientMatch.Groups["quantity"].Value);

                                        currentRecipe.AddReagent(ingredientMatch.Groups["ingredient"].Value, quantity);

                                    }

                                    else

                                    {

                                        success = false;

                                    }

                                }

                                break;

                            case "SearchNodes":

                                int nodeCount = int.Parse(match.Groups["value"].Value);

                                for (int i = 0; i < nodeCount; ++i)

/*

 * Copyright (c) 2015, Jason Maltzen

 Permission is hereby granted, free of charge, to any person obtaining a copy

 of this software and associated documentation files (the "Software"), to deal

 in the Software without restriction, including without limitation the rights

 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 copies of the Software, and to permit persons to whom the Software is

 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in

 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 THE SOFTWARE.

*/

using System;

using System.IO;

using System.Collections.Generic;

using System.Collections.Concurrent;

namespace DesertPaintLab

{

    public partial class RecipeGeneratorWindow : Gtk.Window

    {

        RecipeGenerator generator;

        PlayerProfile profile;

        bool canceling = false;

        bool running = false;

        bool pauseForCheckpoint = false;

        const long RECIPE_SAVE_INTERVAL = 30000; // msec between saving recipes

        const long CHECKPOINT_INTERVAL = 17000; // msec between saving out generator state

        const string STATE_FILE = "dp_generator_state";

        static Gtk.ListStore colorStore = new Gtk.ListStore(typeof(string));

        List<KeyValuePair<string, string>> missingReactions = new List<KeyValuePair<string, string>>();

        long lastProgressUpdate;

        long lastStatusUpdate;

        long lastProfileSave;

        long lastCheckpoint;

        static public Gtk.ListStore RecipeModel

        {

            get

            {

                return colorStore;   

            }

        }

        Gtk.ThreadNotify notifyFinished;

        Gtk.ThreadNotify notifyProgress;

        Gtk.ThreadNotify notifyNewRecipe;

        ConcurrentQueue<PaintRecipe> pendingNewRecipes = new ConcurrentQueue<PaintRecipe>();

        Gtk.ListStore reagentListStore;

        // end reagent view

        public RecipeGeneratorWindow(PlayerProfile profile) : base(Gtk.WindowType.Toplevel)

        {

            this.profile = profile;

            this.Build();

            minIngredientsSpinButton.Value = 1; // TODO: read/save profile info

            maxIngredientsSpinButton.Value = 5; // TODO: read/save profile info

            maxRecipeSpinButton.Value = 20; // TODO: read/save profile info

            fullQuantitySpinButton.Value = 20; // TODO: read/save profile info

            fullQuantityDepthSpinButton.Value = 4; // TODO: read/save profile info

            fullQuantityDepthSpinButton.SetRange(0, ReagentManager.Names.Count);

            maxIngredientsSpinButton.SetRange(1, ReagentManager.Names.Count);

            minIngredientsSpinButton.SetRange(1, ReagentManager.Names.Count);

            Gtk.TreeViewColumn recipeColorColumn = new Gtk.TreeViewColumn();

            Gtk.CellRendererText recipeColumnCell = new Gtk.CellRendererText();

            recipeColorColumn.PackStart(recipeColumnCell, true);       

            recipeColorColumn.Title = "Color";

            recipeList.AppendColumn(recipeColorColumn);

            recipeColorColumn.AddAttribute(recipeColumnCell, "text", 0);

            colorStore.Clear();

            colorStore.SetSortColumnId(0, Gtk.SortType.Ascending);

            recipeList.Model = RecipeModel;

            recipeList.Selection.Changed += OnColorSelected;

            recipeIngredientsView.AppendColumn("Quantity", new Gtk.CellRendererText(), "text", 0);

            recipeIngredientsView.AppendColumn("Ingredient", new Gtk.CellRendererText(), "text", 1);

            recipeIngredientsView.Model = new Gtk.ListStore(typeof(string), typeof(string));

            profile.LoadRecipes();

            // init UI

            foreach (KeyValuePair<string, PaintRecipe> pair in profile.Recipes)

            {

                if (pair.Value.IsValid)

                {

                    string colorName = pair.Key;

                    colorStore.AppendValues(colorName);

                }

            }

            canceling = false;

            running = false;

            pauseForCheckpoint = false;

            generator = new RecipeGenerator(profile.Reactions);

            generator.InitRecipes(profile.Recipes);

            generator.Progress += OnProgress;

            generator.Finished += OnFinished;

            generator.NewRecipe += OnNewRecipe;

            string stateFile = System.IO.Path.Combine(profile.Directory, STATE_FILE);

            if (System.IO.File.Exists(stateFile))

            {

                generator.LoadState(stateFile);

                if (generator.CanResume)

                {

                    beginButton.Label = "Restart";

                    stopResumeButton.Label = "Resume";

                    stopResumeButton.Sensitive = true;

                    maxRecipeSpinButton.Value = Math.Max(generator.MaxQuantity, 14); //

                    fullQuantitySpinButton.Value = generator.FullQuantity; // TODO: read/save profile info

                    fullQuantityDepthSpinButton.Value = generator.FullQuantityDepth; // TODO: read/save profile info

                    maxIngredientsSpinButton.Value = generator.MaxReagents;

                }

            }

            //generator.Log = System.IO.Path.Combine(profile.Directory, "dp_log.txt");

            countLabel.Text = String.Format("{0} / {1}", profile.RecipeCount, Palette.Count);

            Destroyed += OnDestroyed;

            notifyFinished = new Gtk.ThreadNotify(new Gtk.ReadyEvent(HandleFinished));

            notifyProgress = new Gtk.ThreadNotify(new Gtk.ReadyEvent(HandleProgress));

            notifyNewRecipe = new Gtk.ThreadNotify(new Gtk.ReadyEvent(HandleNewRecipe));

            // initialize reagent list

            // Add the columns to the TreeView

            Gtk.TreeViewColumn reagentEnabledColumn = new Gtk.TreeViewColumn ();

            reagentEnabledColumn.Title = "Enabled";

            Gtk.CellRendererToggle reagentEnabledCell = new Gtk.CellRendererToggle ();

            reagentEnabledCell.Activatable = true;

            reagentEnabledCell.Sensitive = true;

            reagentEnabledCell.Mode = Gtk.CellRendererMode.Activatable;

            reagentEnabledCell.Visible = true;

            reagentEnabledCell.Toggled += new Gtk.ToggledHandler(OnReagentEnableToggled);

            reagentEnabledColumn.PackStart (reagentEnabledCell, true);

            //reagentEnabledColumn.AddAttribute(reagentEnabledCell, "active", 0);

            Gtk.TreeViewColumn reagentNameColumn = new Gtk.TreeViewColumn ();

            reagentNameColumn.Title = "Ingredient";

            Gtk.CellRendererText reagentNameCell = new Gtk.CellRendererText ();

            reagentNameCell.Mode = Gtk.CellRendererMode.Inert;

            reagentNameColumn.PackStart (reagentNameCell, true);

            reagentNameColumn.AddAttribute(reagentNameCell, "text", 1);

            reagentNameColumn.Expand = true;

            Gtk.TreeViewColumn reagentCostColumn = new Gtk.TreeViewColumn ();

            reagentCostColumn.Title = "Cost";

            Gtk.CellRendererText reagentCostCell = new Gtk.CellRendererText ();

            reagentCostCell.Edited += OnReagentCostChanged;

            reagentCostCell.Editable = true;

            reagentCostCell.Sensitive = true;

            reagentCostCell.Mode = Gtk.CellRendererMode.Editable;

            reagentCostColumn.PackStart (reagentCostCell, true);

            //reagentCostColumn.AddAttribute(reagentCostCell, "text", 0);

            Gtk.TreeViewColumn reagentMaxColumn = new Gtk.TreeViewColumn ();

            reagentMaxColumn.Title = "Max";

            Gtk.CellRendererText reagentMaxCell = new Gtk.CellRendererText ();

            reagentMaxCell.Edited += OnReagentQuantityChanged;

            reagentMaxCell.Editable = true;

            reagentMaxCell.Sensitive = true;

            reagentCostCell.Mode = Gtk.CellRendererMode.Editable;

            reagentMaxColumn.PackStart (reagentMaxCell, true);

            //reagentMaxColumn.AddAttribute(reagentMaxCell, "text", 0);

            reagentListStore = new Gtk.ListStore(typeof(Reagent), typeof(string), typeof(Reagent), typeof(Reagent));

            foreach (string reagentName in ReagentManager.Names)

            {

                Reagent reagent = ReagentManager.GetReagent(reagentName);

                reagentListStore.AppendValues(reagent, reagentName); // , reagent, reagent);

            }

            reagentEnabledColumn.SetCellDataFunc (reagentEnabledCell, new Gtk.TreeCellDataFunc (RenderReagentToggle));

            reagentCostColumn.SetCellDataFunc (reagentCostCell, new Gtk.TreeCellDataFunc (RenderReagentCost));

            reagentMaxColumn.SetCellDataFunc (reagentMaxCell, new Gtk.TreeCellDataFunc (RenderReagentQuantity));

            // Assign the model to the TreeView

            reagentListView.Model = reagentListStore;

            reagentListView.Sensitive = true;

            reagentListView.AppendColumn(reagentEnabledColumn);

            reagentListView.AppendColumn(reagentNameColumn);

            reagentListView.AppendColumn(reagentCostColumn);

            reagentListView.AppendColumn(reagentMaxColumn);

            reagentListView.

            ShowAll();

        }

        protected void OnMinIngredientsChanged(object sender, EventArgs e)

        {

            Gtk.SpinButton button = (Gtk.SpinButton) sender;

            if (button.ValueAsInt > maxIngredientsSpinButton.ValueAsInt)

            {

                maxIngredientsSpinButton.Value = button.ValueAsInt;

            }

            maxIngredientsSpinButton.SetRange(button.ValueAsInt, maxIngredientsSpinButton.Adjustment.Upper);

        }

        protected void OnMaxIngredientsChanged(object sender, EventArgs e)

        {

            Gtk.SpinButton button = (Gtk.SpinButton) sender;

            if (button.ValueAsInt < minIngredientsSpinButton.ValueAsInt)

            {

                minIngredientsSpinButton.Value = button.ValueAsInt;

            }

            minIngredientsSpinButton.SetRange(1, button.ValueAsInt);

            // TODO: save profile setting

            // TODO: no longer permit resume

        }

        protected void OnMaxRecipeChanged(object sender, EventArgs e)

        {

            // TODO: save profile setting

            // TODO: no longer permit resume

        }

        protected void OnFullQuantityDepthChanged(object sender, EventArgs e)

        {