/* -*- coding: utf-8 -*-
 *
 * Copyright (C) 2010 by Atzm WATANABE <atzm@atzm.org>
 *
 *  This program is free software; you can redistribute it and/or modify it
 *  under the terms of the GNU General Public License (version 2) as
 *  published by the Free Software Foundation.  It is distributed in the
 *  hope that it will be useful, but WITHOUT ANY WARRANTY; without even the
 *  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 *  PURPOSE.  See the GNU General Public License for more details.
 *
 * $Id$
 *
 */

System = {
    "screen": {
        "canvas": null,
        "ctx":    null,
        "width":  0,
        "height": 0
    },
    "sound":            {},
    "message":          null,
    "enemyImages":      new Array(),
    "enemies":          new Array(),
    "players":          new Array(),
    "score":            {},
    "stage":            -1,
    "round":            1,
    "backgroundObject": new Array(),
    "deathPieces":      new Array(),
    "items":            new Array(),
    "mainIntervalId":   0
};


/*
 *  Tiun Tiun Utilities
 */
var DeathPiece = function(sizes, colors, x, y, dir, speed) {
    var that = new LinerBullet(sizes[0], colors[0], null,
                               System.screen.width, System.screen.height,
                               x, y, dir, speed);

    var sizeIdx  = -1;
    var colorIdx = -1;

    that.getSize = function() {
        if (++sizeIdx >= sizes.length)
            sizeIdx = 0;
        return sizes[sizeIdx];
    };

    that.getColor = function() {
        if (++colorIdx >= colors.length)
            colorIdx = 0;
        return colors[colorIdx];
    };

    return that;
};

function addDeathPieces(x, y, sizes, colors, speed, way) {
    if (way % 2)
        way++;

    var pieces = new Array();
    var angle  = 0;
    var delta  = 2 / way;

    for(var i = 0; i < way; i++) {
        pieces.push(new DeathPiece(sizes, colors, x, y, angle * Math.PI, speed));
        angle += delta;
    }

    System.deathPieces.push(pieces);
}

function updateDeathPieces(ctx, width, height) {
    var newObjs = new Array();

    for (var i = 0; i < System.deathPieces.length; i++) {
        var pieces    = System.deathPieces[i];
        var newPieces = new Array();

        for (var k = 0; k < pieces.length; k++) {
            pieces[k].next();
            pieces[k].draw(ctx);
            if (!pieces[k].vanished(width, height))
                newPieces.push(pieces[k]);
        }

        if (newPieces.length)
            newObjs.push(newPieces);
    }

    System.deathPieces = newObjs;
}


/*
 *  Item Utilities
 */
function addItem(x, y, angle, size, color, speed, attrs) {
    var frame = {"style": "rect", "color": attrs.color, "width": size * 2, "height": size * 2};
    var item  = new YExtendBullet(size, color, frame,
                                  System.screen.width, System.screen.height,
                                  x, y, angle * Math.PI, speed);
    item.attrs = attrs;
    System.items.push(item);
}

function updateItems(ctx, width, height, troopers) {
    var newObjs = new Array();

  ITEMLOOP:
    for (var i = 0; i < System.items.length; i++) {
        var item = System.items[i];

        item.next();
        item.draw(ctx, function(bullet, ctx) {
            drawString(
                ctx, "source-over", item.attrs.symbol,
                bullet.x, bullet.y,
                item.attrs.color, item.size + "pt monospace", "center"
            );
        });

        for (var j = 0; j < troopers.length; j++) {
            var trooper = troopers[j];

            if (touch(trooper.x, trooper.y, trooper.size, item.x, item.y, item.size)) {
                switch (item.attrs.type) {
                case "score":
                    playSound("se_item_score");
                    if (System.score[trooper.name] !== undefined)
                        System.score[trooper.name] += item.attrs.quantity;
                    break;
                case "shot":
                    playSound("se_item_shot");
                    for (var k = 0; k < trooper.barrages.length; k++) {
                        trooper.barrages[k].way += item.attrs.quantity;
                        if (trooper.barrages[k].way >= 5)
                            trooper.barrages[k].way = 5;
                    }
                    break;
                case "wide":
                    playSound("se_item_wide");
                    for (var k = 0; k < trooper.barrages.length; k++) {
                        trooper.barrages[k].size += item.attrs.quantity;
                        if (trooper.barrages[k].size >= 12)
                            trooper.barrages[k].size = 12;
                    }
                    break;
                case "bomb":
                    playSound("se_item_bomb");
                    trooper.numBombs += item.attrs.quantity;
                    break;
                case "life":
                    playSound("se_item_life");
                    trooper.life += item.attrs.quantity;
                    break;
                }

                continue ITEMLOOP;
            }
        }

        if (!item.vanished(width, height))
            newObjs.push(item);
    }

    System.items = newObjs;
}


/*
 *  Utility Functions
 */
function setMessage(elem, msg) {
    if (elem)
        elem.innerHTML = msg;
}

function addMessage(elem, msg) {
    if (elem)
        elem.innerHTML += msg;
}

function updateBackground(ctx, width, height, size, color, max) {
    if (System.backgroundObject.length < max) {
        var x = Math.ceil(Math.random() * width);
        var s = Math.ceil(Math.random() * 5);
        System.backgroundObject.push(
            new LinerBullet(size, color, null,
                            System.screen.width, System.screen.height,
                            x, 0, 0.5 * Math.PI, s));
    }

    var newObjs = new Array();

    for (var i = 0; i < System.backgroundObject.length; i++) {
        System.backgroundObject[i].next();
        System.backgroundObject[i].draw(ctx);
        if (!System.backgroundObject[i].vanished(width, height))
            newObjs.push(System.backgroundObject[i]);
    }

    System.backgroundObject = newObjs;
}

function drawScreen(ctx, op, style, width, height) {
    var c = ctx.globalCompositeOperation;
    ctx.globalCompositeOperation = op;
    ctx.beginPath();
    ctx.fillStyle = style;
    ctx.fillRect(0, 0, width, height);
    ctx.fill();
    ctx.closePath();
    ctx.globalCompositeOperation = c;
}

function drawLifeGauge(ctx, op, trooper, x, y, width) {
    var length = trooper.life;

    if (length > width - 20)
        length = width - 20;

    var c = ctx.globalCompositeOperation;
    ctx.globalCompositeOperation = op;
    ctx.beginPath();
    ctx.fillStyle = trooper.color;
    ctx.fillRect(x, y, length, 10);
    ctx.fill();
    ctx.closePath();
    ctx.globalCompositeOperation = c;

    drawString(ctx, op, trooper.life, x + 2, y + 8, trooper.color,
               "6pt monospace", "left");
}

function drawString(ctx, op, string, x, y, color, font, align) {
    var a = ctx.textAlign;
    var f = ctx.font;
    var c = ctx.globalCompositeOperation;
    ctx.globalCompositeOperation = op;
    ctx.beginPath();
    ctx.textAlign = align;
    ctx.fillStyle = color;
    ctx.font      = font;
    ctx.fillText(string, x, y);
    ctx.fill();
    ctx.textAlign = a;
    ctx.font      = f;
    ctx.closePath();
    ctx.globalCompositeOperation = c;
}

function updateTrooper(trooper, enemyKey) {
    trooper.update(System[enemyKey]);

    var aliveEnemies = new Array();
    for (var i = 0; i < System[enemyKey].length; i++) {
        var enemy = System[enemyKey][i];

        if (enemy.isDead()) {
            if (System.score[trooper.name] !== undefined) {
                System.score[trooper.name] += enemy.maxLife * 100;
            }
        }
        else {
            aliveEnemies.push(enemy);
        }
    }
    System[enemyKey] = aliveEnemies;

    trooper.draw(System.screen.ctx);
}

function getStageNumber() {
    return System.stage;
}

function getRoundNumber() {
    return System.round;
}

function switchStage(base) {
    var scores   = Object.keys(System.score);
    var sum      = 0;
    var stages   = new Array();
    var score    = 0;
    var stage    = 1;
    var switched = false;

    for (var i = 0; i < scores.length; i++) {
        sum += System.score[scores[i]];
    }

    for (var name in System.sound) {
        if (!name.match(/^bgm_stage/)) continue;
        stages.push(name);
    }

    score        = Math.round(sum / scores.length);
    stage        = Math.floor((score % (stages.length * base)) / base) + 1;
    switched     = System.stage != stage;
    System.round = System.stage > stage ? System.round + 1 : System.round;
    System.stage = stage;

    return switched;
}

function switchBgm(stage) {
    for (var name in System.sound) {
        if (!name.match(/^bgm_stage/))
            continue;
        if (("bgm_stage" + stage) == name)
            playSound(name);
        else
            pauseSound(name, true);
    }
}

function toggleSound(val) {
    for (var name in System.sound)
        System.sound[name].muted = !val;
}

function registerSound(name, audio) {
    System.sound[name] = audio;
}

function playSound(name) {
    if (System.sound[name])
        System.sound[name].play();
}

function pauseSound(name, stop) {
    if (System.sound[name]) {
        System.sound[name].pause();
        if (stop)
            System.sound[name].currentTime = 0;
    }
}

function getEnemiesOnScreen() {
    return System.enemies.length;
}

function addEnemyImage(image) {
    System.enemyImages.push(image);
}

function addEnemy(enemyData) {
    var actList = EnemyActionLists[enemyData.mtime % EnemyActionLists.length];
    var shot    = EnemyShots[enemyData.hitpoint % EnemyShots.length];
    var numAct  = enemyData.agility       % (EnemyActions.length  - 1) + 1;
    var numBlt  = enemyData.skills.length % (EnemyBullets.length  - 1) + 1;
    var numBrrg = enemyData.skills.length % (EnemyBarrages.length - 1) + 1;
    var acts    = new Array();
    var brrgs   = new Array();

    var bulletWay         = Math.ceil(enemyData.concentration / 10) * getRoundNumber();
    var bulletInterval    = Math.round(50 * 1 / Math.log(enemyData.skillpoint + 0.1));
    var bulletSize        = Math.round(Math.log(enemyData.luck + 1));
    var bulletFrameWidth  = (bulletSize + 5) * 2;
    var bulletFrameHeight = (bulletSize + 5) * 4;
    var bulletSpeed       = (enemyData.strength / 15) * getRoundNumber();

    bulletSpeed = Math.log(bulletSpeed < 1.5 ? 1.5 : bulletSpeed);

    for (var i = 0; i < numAct; i++) {
        var idx = (enemyData.agility + i) % EnemyActions.length;
        acts.push(new EnemyActions[idx](new shot()));
    }

    for (var i = 0; i < numBrrg; i++) {
        var idx     = (enemyData.skillpoint + i * (enemyData.skills.length + 1)) % EnemyBarrages.length;
        var brrgCls = EnemyBarrages[idx];
        var frameColor;

        switch(idx % 3) {
        case 0:
            frameColor = "rgba(128,32,32,0.7)";
            break;
        case 1:
            frameColor = "rgba(32,128,32,0.7)";
            break;
        default:
            frameColor = "rgba(64,64,128,0.7)";
        }

        for (var k = 0; k < numBlt; k++) {
            var iidx = (enemyData.skills.length + i + k) % EnemyBullets.length;
            brrgs.push(
                new brrgCls(
                    EnemyBullets[iidx],
                    bulletSize,
                    "#FF3",
                    {"style": "rect", "color": frameColor,
                     "width": bulletFrameWidth, "height": bulletFrameHeight},
                    bulletInterval,
                    bulletSpeed,
                    bulletWay
                )
            );
        }
    }

    var size  = Math.ceil((System.screen.width / 2) * (1 / enemyData.defense));
    var enemy = new Trooper(
        enemyData.name,
        new actList(acts),
        System.enemyImages[enemyData.hitpoint % System.enemyImages.length],
        size,
        size,
        "#F33",
        "#F33",
        Math.floor(Math.random() * System.screen.width),
        Math.floor(Math.random() * (System.screen.height / 4)),
        System.screen.width,
        System.screen.height,
        Math.floor(enemyData.hitpoint / 25) + 1,
        Math.log(enemyData.agility + 0.1) * 3,
        0,
        ["rgba(255,0,0,0.3)", "rgba(0,0,255,0.3)"],
        brrgs
    );

    enemy.registerCallback("damaged", function() {
        if (enemy.isDead()) {
            playSound("se_destroy");

            addDeathPieces(
                enemy.x, enemy.y,
                [6, 8, 10], ["#F55", "#FAA"], 3, 8
            );

            var itemAttr = null;

          PLAYERSLOOP:
            for (var i = 0; i < System.players.length; i++) {
                for (var k = 0; k < System.players[i].barrages.length; k++) {
                    if (System.players[i].barrages[k].way <= 1) {
                        itemAttr = {"color": "#FAA", "symbol": "P", "type": "shot", "quantity": 1};
                        break PLAYERSLOOP;
                    }
                }
            }

            if (!itemAttr) {
                var itemRand = Math.floor(Math.random() * 100);
                if (itemRand < 40) {
                    // nothing
                }
                else if (itemRand < 70) {
                    itemAttr = {"color": "#AAF", "symbol": "S", "type": "score", "quantity": enemy.maxLife * 200};
                }
                else if (itemRand < 85) {
                    itemAttr = {"color": "#FAA", "symbol": "P", "type": "shot", "quantity": 1};
                }
                else if (itemRand < 95) {
                    itemAttr = {"color": "#A5F", "symbol": "W", "type": "wide", "quantity": 1};
                }
                else if (itemRand < 98) {
                    itemAttr = {"color": "#FFA", "symbol": "B", "type": "bomb", "quantity": 1};
                }
                else {
                    itemAttr = {"color": "#AFA", "symbol": "L", "type": "life", "quantity": 1};
                }
            }

            if (itemAttr)
                addItem(enemy.x, enemy.y, 0.5, 5, "#AFA", 1, itemAttr);
        }
        else {
            playSound("se_damage");
        }
    });

    System.enemies.push(enemy);
}


/*
 *  Main loop
 */
function mainLoop() {
    // clear screen
    drawScreen(
        System.screen.ctx,
        "source-over",
        "rgba(8,8,8,0.8)",
        System.screen.width,
        System.screen.height
    );

    // update background objects
    updateBackground(
        System.screen.ctx,
        System.screen.width,
        System.screen.height,
        1, "#CAF", 10
    );

    // switch stage
    if (switchStage(50000))
        switchBgm(getStageNumber());

    // draw stage number
    drawString(
        System.screen.ctx,
        "source-over",
        "ROUND " + getRoundNumber() + " / STAGE " + getStageNumber(),
        System.screen.width - 10,
        15,
        "#ACF", "9pt monospace", "right"
    );

    // draw score
    var scoreNames = Object.keys(System.score).sort();
    for (var i = 0; i < scoreNames.length; i++) {
        var name = scoreNames[i];
        drawString(
            System.screen.ctx,
            "source-over",
            name + " SCORE " + System.score[name],
            (System.screen.width - 10),
            i * 16 + 30,
            "#ACF", "9pt monospace", "right"
        );
    }

    // update/draw items
    updateItems(System.screen.ctx,
                System.screen.width,
                System.screen.height,
                System.players);

    // update/draw troopers
    for (var i = 0; i < System.players.length; i++) {
        var player = System.players[i];

        updateTrooper(player, "enemies");

        drawLifeGauge(
            System.screen.ctx,
            "lighter",
            player,
            10,
            (System.screen.height - 20) - (i * 33),
            System.screen.width
        );

        drawString(
            System.screen.ctx,
            "source-over",
            player.name,
            10,
            (System.screen.height - 23) - (i * 33),
            "#ACF", "9pt monospace", "left"
        );

        drawString(
            System.screen.ctx,
            "source-over",
            "BOMB " + player.numBombs,
            (System.screen.width - 10),
            (System.screen.height - 23) - (i * 33),
            "#ACF", "9pt monospace", "right"
        );
    }

    // update/draw enemies
    for (var i = 0; i < System.enemies.length; i++) {
        var enemy = System.enemies[i];

        updateTrooper(enemy, "players");

        drawLifeGauge(
            System.screen.ctx,
            "lighter",
            enemy, 10, i * 33 + 10,
            System.screen.width
        );

        drawString(
            System.screen.ctx,
            "source-over",
            enemy.name, 10, i * 33 + 33,
            "#FCA", "9pt monospace", "left"
        );
    }

    updateDeathPieces(System.screen.ctx,
                      System.screen.width,
                      System.screen.height);

    if (!System.players.length) {
        drawString(
            System.screen.ctx, "source-over",
            "GAME OVER",
            System.screen.width / 2,
            System.screen.height / 2,
            "#ACF", "24pt monospace", "center"
        );
    }
}


/*
 *  Initializer
 */
function initGame(canvas, msg, playerData, scoreCallback) {
    System.screen.canvas = canvas;
    System.message       = msg;
    System.screen.ctx    = System.screen.canvas.getContext("2d");
    System.screen.width  = System.screen.canvas.width;
    System.screen.height = System.screen.canvas.height;
    System.gameOver      = false;

    System.screen.ctx.globalCompositeOperation = "lighter";

    if (System.mainIntervalId) {
        clearInterval(System.mainIntervalId);
        System.mainIntervalId   = 0;
        System.players          = new Array();
        System.enemies          = new Array();
        System.backgroundObject = new Array();
        System.deathPieces      = new Array();
    }

    var trooper = new Trooper(
        playerData.name,
        new ActionList([new ManualAction(new ManualShot())]),
        playerData.image,
        playerData.size,
        playerData.hitsize,
        "#33F",
        "#F33",
        System.screen.width / 2,
        System.screen.height - System.screen.height / 7,
        System.screen.width,
        System.screen.height,
        playerData.hitpoint,
        playerData.speed,
        playerData.numbombs,
        ["rgba(255,0,0,0.3)", "rgba(0,0,255,0.3)"],
        [new LinerBarrage(YExtendBullet,
                          playerData.shotsize,
                          "rgba(64,64,128,0.4)",
                          null,
                          playerData.shotinterval,
                          playerData.shotspeed,
                          playerData.shotlevel,
                          -0.5),
         new LinerBarrage(LinerBullet,
                          playerData.shotsize,
                          "rgba(64,64,128,0.4)",
                          null,
                          playerData.shotinterval,
                          playerData.shotspeed,
                          playerData.shotlevel,
                          -0.5)]
    );
    trooper.registerCallback("addBomb", function() { playSound("se_bomb"); });
    trooper.registerCallback("damaged", function() {
        playSound("se_destroy");

        addDeathPieces(
            trooper.x, trooper.y,
            [6, 8, 10], ["#55F", "#AAF"], 3, 8
        );

        for (var i = 0; i < System.enemies.length; i++) {
            System.enemies[i].clearBullet();
        }

        trooper.x = System.screen.width / 2;
        trooper.y = System.screen.height - System.screen.height / 7;
        trooper.numBombs = playerData.numbombs;
        trooper.barrages = [
            new LinerBarrage(YExtendBullet,
                             playerData.shotsize,
                             "rgba(64,64,128,0.4)",
                             null,
                             playerData.shotinterval,
                             playerData.shotspeed,
                             playerData.shotlevel,
                             -0.5),
            new LinerBarrage(LinerBullet,
                             playerData.shotsize,
                             "rgba(64,64,128,0.4)",
                             null,
                             playerData.shotinterval,
                             playerData.shotspeed,
                             playerData.shotlevel,
                             -0.5)
        ];

        if (trooper.isDead() && scoreCallback) {
            scoreCallback(trooper.name, System.score[trooper.name]);
        }
    });

    System.players.push(trooper);

    for (var i = 0; i < System.players.length; i++) {
        System.score[System.players[i].name] = 0;
    }

    drawScreen(
        System.screen.ctx,
        "source-over",
        "rgba(0,0,0,1)",
        System.screen.width,
        System.screen.height
    );

    document.onkeydown  = function (ev) { setKeyDown(ev.keyCode); };
    document.onkeyup    = function (ev) { setKeyUp(ev.keyCode); };
    document.onkeypress = function (ev) { setKeyPress(ev.charCode); };

    System.mainIntervalId = setInterval(mainLoop, 20);
}