// requirements
const logger = require('./logger');

// third party requirements
const blinkstick = require('blinkstick');
const async = require('async');
const hexcolor = require('hex-color-regex');

// constants
const COLORTYPE_RGB = "rgb";
const COLORTYPE_HEX = "hex";
const ANIMATION_STATE_INFINITE = 2;
const ANIMATION_STATE_INPROGRESS = 1;
const ANIMATION_STATE_FINISH = 0;

// variables
let led;
let animation = {};

function findBlinkstick() {
    return new Promise(function (resolve, reject) {
        led = blinkstick.findFirst();
        if (led !== undefined && led !== null) {
            return resolve(led);
        }
        return reject("could not find any blinkstick");
    });
}

// turn the blinkstick off 
function powerOff() {
    led.turnOff();
    logger.info("blinkstick powered off");
}

// parse a color object from given request arguments
function parseColor(blinkstickConfig) {
    return new Promise(function (resolve, reject) {
        if (blinkstickConfig.color == "random") {
            resolve(color);
        }
        if (blinkstickConfig.color == undefined || blinkstickConfig.color.length === 0) {
            reject("no hex color code given, request will be ignored");
        }
        let parsedColor = parseRGBColor(blinkstickConfig.color);
        if (!parsedColor) {
            parsedColor = parseHexColor(blinkstickConfig.color);
        }
        if (!parsedColor) {
            return reject("could not parse given color code '" + color + "'");
        }
        blinkstickConfig.color = parsedColor;
        resolve(blinkstickConfig);
    });
}

// parse rgb color values
function parseRGBColor(colorValues) {
    let color = {};
    if (colorValues.indexOf(",") == -1) {
        if (isRGBValue(colorValues)) {
            color.type = COLORTYPE_RGB;
            color.red = parseInt(colorValues);
            return color;
        }
    } else {
        const splittedValues = colorValues.split(",");
        for (let index = 0; index < splittedValues.length; index++) {
            const value = splittedValues[index];
            if (!isRGBValue(value)) {
                continue;
            }
            if (index == 0) {
                color.red = parseInt(value);
            } else if (index === 1) {
                color.green = parseInt(value);
            } else if (index === 2) {
                color.blue = parseInt(value);
            }
        }
        if (color && (color.red || color.green || color.blue)) {
            color.type = COLORTYPE_RGB;
            return color;
        }
    }
    if (isRGBValue(colorValues.red) || isRGBValue(colorValues.green) || isRGBValue(colorValues.blue)) {
        color.type = COLORTYPE_RGB;
        return colorValues;
    }
    return undefined;
}

// check a single rgb value
function isRGBValue(value) {
    return value != undefined && value.length > 0 && !isNaN(value) && value >= 0 && value <= 255;
}

// parse hex color values
function parseHexColor(colorValues) {
    if (colorValues[0] !== '#') {
        colorValues = '#' + colorValues;
    }
    if (colorValues.length === 4) {
        colorValues.type = COLORTYPE_HEX;
        return (colorValues[0] + colorValues[1] + colorValues[1] + colorValues[2] + colorValues[2] + colorValues[3] + colorValues[3]);
    }
    if (colorValues.length === 7 && hexcolor({ strict: true }).test(colorValues)) {
        colorValues.type = COLORTYPE_HEX;
        return colorValues;
    }
    return undefined;
}

// pass the options to the blinkstick accordingly
function illuminate(blinkstickConfig) {
    return new Promise(function (resolve, reject) {
        waitForAnimation
        let color;
        findBlinkstick().then(function () {
            if (blinkstickConfig.color.type === COLORTYPE_HEX) {
                color = blinkstickConfig.color.red;
            } else {
                color = blinkstickConfig.color.red + ", " + blinkstickConfig.color.green + ", " + blinkstickConfig.color.blue;
            }
            switch (blinkstickConfig.mode) {
                case "morph":
                    morph(blinkstickConfig, color, resolve, reject);
                    break;
                case "pulse":
                    startPulsing(blinkstickConfig, color, resolve, reject);
                    break;
                default:
                    setColor(blinkstickConfig, color, resolve, reject);
                    break;
            }
        })
            .catch(reject);
    });
}

// set a static color
function setColor(blinkstickConfig, color, resolve, reject) {
    stopAnimation()
        .then(function () {
            setAnimationProperties(blinkstickConfig);
            led.setColor(blinkstickConfig.color.red, blinkstickConfig.color.green, blinkstickConfig.color.blue, function (err) {
                clearAnimationProperties();
                logger.debug("setting color to '" + color + "'...");
                if (err) {
                    return reject("error setting color '" + color + "' (" + err + ")");
                }
                return resolve("set color to '" + color + "'");
            });
        });
}

// morph to a color
function morph(blinkstickConfig, color, resolve, reject) {
    stopAnimation()
        .then(function () {
            setAnimationProperties(blinkstickConfig);
            led.morph(blinkstickConfig.color.red, blinkstickConfig.color.green, blinkstickConfig.color.blue, blinkstickConfig.options, function (err) {
                clearAnimationProperties();
                logger.debug("morphing color to '" + color + "'...");
                if (err) {
                    return reject("error morphing color to '" + color + "' (" + err + ")");
                }
                return resolve("morphed color to '" + color + "'");
            });
        });
}

// start pulsing
function startPulsing(blinkstickConfig, color, resolve, reject) {
    if (animation.state == ANIMATION_STATE_FINISH || (blinkstickConfig.options.pulse.max > 0 && (blinkstickConfig.options.pulse.done && blinkstickConfig.options.pulse.done < blinkstickConfig.options.pulse.max))) {
        clearAnimationProperties();
        return resolve("finished pulsing color '" + color + "'");
    }
    if (animation.id && animation.id != blinkstickConfig.id) {
        stopAnimation()
            .then(logger.info)
            .then(function () {
                startPulsing(blinkstickConfig, color, resolve, reject)
            })
            .catch(logger.error);
        return;
    }
    setAnimationProperties(blinkstickConfig);
    led.pulse(blinkstickConfig.color.red, blinkstickConfig.color.green, blinkstickConfig.color.blue, blinkstickConfig.options, function (err) {
        if (err) {
            clearAnimationProperties();
            return reject("error pulsing color '" + color + "' (" + err + ")");
        }
        blinkstickConfig.options.pulse.done++;
        logger.debug("pulsed color '" + color + "' " + blinkstickConfig.options.pulse.done + "/" + blinkstickConfig.options.pulse.max + " times");
        startPulsing(blinkstickConfig, color, resolve, reject);
    });
}

// set properties for the current animation
function setAnimationProperties(blinkstickConfig) {
    if (animation.id == blinkstickConfig.id) {
        return;
    }
    led.animationsEnabled = true;
    animation.id = blinkstickConfig.id;
    if (blinkstickConfig.options.pulse && blinkstickConfig.options.pulse.max === 0) {
        animation.state = ANIMATION_STATE_INFINITE;
    } else {
        animation.state = ANIMATION_STATE_INPROGRESS;
    }
}

// clear properties for the current animation
function clearAnimationProperties() {
    led.stop();
    animation = {};
}

// stop the current animation  
function stopAnimation() {
    return new Promise(function (resolve, reject) {
        if (!isAnimationInProgress()) {
            return resolve();
        }
        animation.state = ANIMATION_STATE_FINISH;
        waitForAnimation(Date.now(), resolve, reject);
    });
}

// wait for current animation
function waitForAnimation(timestamp, resolve, reject) {
    if (!isAnimationInProgress()) {
        return resolve();
    }
    setTimeout(function () {
        waitForAnimation(timestamp, resolve, reject);
    }, 100);
}

// is currently an animation in progress
function isAnimationInProgress() {
    return animation != undefined && animation.state != undefined;
}

// is currently an infinite animation in progress
function isInfiniteAnimationInProgress() {
    return isAnimationInProgress() && animation.state == ANIMATION_STATE_INFINITE;
}

// exports
module.exports = {
    parseColor,
    illuminate,
    isAnimationInProgress,
    isInfiniteAnimationInProgress,
    stopAnimation,
    powerOff
};