const { unitScale } = require('./index')

const interpolate = ({ x, y, from }) => {
    const [x1, x2] = x
    const [y1, y2] = y
    const to = y1 + (y2-y1) / (x2-x1) * (from-x1)
    return to
}

class Base {
    constructor({ name, min, max, unit, scale }) {
        this.name = name
        this.unit = unit
        this.scale = scale
        this.max = max
        this.min = min
        this._value = null
    }
    get value() { return this._value }
    get aboveRange() {
        return this._value > this.max
    }
    get belowRange() {
        return this._value < this.max
    }
    get inRange() {
        return this._value && this._value <= this.max && this._value >= this.min ? true : false
    }
}

class Channel extends Base {
    constructor({ name, min, max, interval=1, unit, scale }) {
        super({ name, min: min * interval, max: max * interval, unit, scale })
        this._interval = interval
    }
    readFrom(sensor) {
        const from = sensor.value
        this._value = interpolate({
            x: [sensor.min, sensor.max],
            y: [this.min, this.max],
            from
        })
        return Math.round(this.value)
    }
}

class Sensor extends Base {
    constructor({ name, min, max, interval=1, unit=unitScale.mV.unit, scale=unitScale.mV.scale }) {
        super({ name, min: min * interval, max: max * interval, unit, scale })
        this._interval = interval
    }
}
class TempSensor extends Sensor {
    constructor({ min, max, interval, unit, scale }) {
        super({ name: 'temperature_sensor', min, max, interval, unit, scale })
    }
    update() {
        // Store data in this._value
        this._value = 300
        return this
    }
}
class LevelSensor extends Sensor {
    constructor({ min, max, interval=1, unit="millimeter" }) {
        super({ name: 'level_sensor', min, max, interval, unit })
    }
    update() {
        // Store data in this._value
        return this
    }
}

module.exports = {
    Channel,
    TempSensor,
}