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

const LED_ANIMATED = 0;

const LEDS_ALL = 'all';

const MODE_SET = 'set';
const MODE_MORPH = 'morph';
const MODE_BLINK = 'blink';
const MODE_PULSE = 'pulse';
const MODE_POWEROFF = 'poweroff';

const LEDS = new Map();

let stop = false;

// find a connected blinkstick
function findBlinkstick() {
    return new Promise((resolve, reject) => {
        let led = blinkstick.findFirst();
        if (led === undefined) {
            reject('could not find any blinkstick');
        }
        resolve(led);
    });
}

// simple animation (set the color / morph to color)
async function simple(config) {
    try {
        await forceStop();
        config.timestamp = new Date().getTime();
        let indices = getIndices(config);
        for (let index = 0; index < indices.length; index++) {
            await setLedState(indices[index], LED_ANIMATED);
            await singleAnimation(JSON.parse(JSON.stringify(config)), indices[index]);
            await clearLedState(indices[index]);
        }
        return {
            status: 'ok',
            color: config.color,
            indices: indices,
            time: (new Date().getTime() - config.timestamp) + 'ms'
        };
    } catch (err) {
        logger.error(err);
        return err;
    }
}

// complex animation (pulse / blink)
async function complex(config) {
    try {
        if (config.timestamp === undefined) {
            await powerOff({id: Math.random(), mode: MODE_POWEROFF, color: '#000000', options: {index: LEDS_ALL}});
            config.timestamp = new Date().getTime();
        }
        let indices = getIndices(config);
        for (let index = 0; index < indices.length; index++) {
            if (shouldLedFinish(config)) {
                return {status: 'ok', time: (new Date().getTime() - config.timestamp) + 'ms'};
            }
            await setLedState(indices[index], LED_ANIMATED);
            await singleAnimation(JSON.parse(JSON.stringify(config)), indices[index]);
            await clearLedState(indices[index]);
            config.repetitions.done++;
        }
        return complex(config);
    } catch (err) {
        logger.error(err);
        return err;
    }
}

// power the blinkstick (or just a specific led) off
async function powerOff(config) {
    try {
        await forceStop();
        config.timestamp = new Date().getTime();
        let indices = getIndices(config);
        for (let index = 0; index < indices.length; index++) {
            await singleAnimation(JSON.parse(JSON.stringify(config)), indices[index]);
            logger.info('led \'' + indices[index] + '\' powered off');
        }
        if (config.options.index === LEDS_ALL) {
            const blinkstick = await findBlinkstick();
            blinkstick.stop();
            blinkstick.turnOff();
            logger.info('blinkstick powered off');
        }
        return {status: 'ok', indices: indices, time: (new Date().getTime() - config.timestamp) + 'ms'};
    } catch (err) {
        return err;
    }
}

// animations
async function singleAnimation(config, index) {
    try {
        config.options.index = index;
        const blinkstick = await findBlinkstick();
        return await new Promise((resolve, reject) => {
            logger.debug('changing color of led \'' + config.options.index + '\' to \'' + config.color + '\' (mode: ' + config.mode + ')...');
            switch (config.mode) {
                case MODE_MORPH:
                    blinkstick.morph(config.color, config.options, callback);
                    break;
                case MODE_BLINK:
                    blinkstick.blink(config.color, config.options, callback);
                    break;
                case MODE_PULSE:
                    blinkstick.pulse(config.color, config.options, callback);
                    break;
                default:
                    blinkstick.setColor(config.color, config.options, callback);
                    break;
            }

            function callback(err) {
                if (err) {
                    reject('changing color of led \'' + config.options.index + '\' to \'' + config.color + '\' encountered an error > ' + err);
                }
                logger.debug('changed color of led \'' + config.options.index + '\' to \'' + config.color + '\' (mode: ' + config.mode + ')');
                resolve();
            }
        });
    } catch (err) {
        return err;
    }
}

async function forceStop() {
    return new Promise((resolve, reject) => {
        stop = true;
        waitForAllAnimationsEnd(() => {
            stop = false;
            resolve();
        });
    });
}

function shouldLedFinish(config) {
    if (stop) {
        return true;
    }
    if (config.mode === MODE_BLINK && config.mode === MODE_PULSE) {
        return config.repetitions.max !== 0 && config.repetitions.done >= config.repetitions.max
    }
    return false;
}

// led / index helper functions
function getIndices(blinkstickConfig) {
    if (blinkstickConfig.options.index === LEDS_ALL) {
        return [0, 1, 2, 3, 4, 5, 6, 7];
    }
    return [blinkstickConfig.options.index];
}

async function setLedState(index, state) {
    await stopLedAnimation(index);
    LEDS.set(index, state);
}

function clearLedState(index) {
    return new Promise((resolve, reject) => {
        LEDS.delete(index);
        resolve();
    });
}

function isLedAnimated(index) {
    return (LEDS.get(index) || LEDS.get(LEDS_ALL)) !== undefined;
}

function stopLedAnimation(index) {
    return new Promise((resolve, reject) => {
        waitForAnimationEnd(index, () => {
            resolve();
        });
    });
}

function waitForAnimationEnd(index, callback) {
    if (!isLedAnimated(index)) {
        return callback();
    }
    setTimeout(() => {
        waitForAnimationEnd(index, callback);
    }, 100);
}

function waitForAllAnimationsEnd(callback) {
    if (LEDS.size === 0) {
        return callback();
    }
    setTimeout(() => {
        waitForAllAnimationsEnd(callback);
    }, 100);
}

function isInfiniteAnimation(config) {
    if (config.mode !== MODE_BLINK && config.mode !== MODE_PULSE) {
        return false;
    }
    if (config.options.index === LEDS_ALL) {
        return config.repetitions.max === 0;
    }
    return config.options.repeats === 0;
}

// exports
module.exports = {
    simple,
    complex,
    powerOff,
    isInfiniteAnimation,
    LEDS_ALL,
    MODE_SET,
    MODE_MORPH,
    MODE_BLINK,
    MODE_PULSE,
    MODE_POWEROFF
};