#include <Arduino.h>
#include <U8x8lib.h>
#include <EncButton.h>
#include <FastLED.h>

#define NUM_LEDS 8
const uint8_t ledPin = 5;
const uint8_t s1Pin = 3;
const uint8_t s2Pin = 4;
const uint8_t btnPin = 2;
CRGB leds[NUM_LEDS];

//U8X8_SH1106_128X64_NONAME_HW_I2C
U8X8_SSD1306_128X64_NONAME_HW_I2C u8x8(U8X8_PIN_NONE);
EncButton enc(s1Pin, s2Pin, btnPin);


typedef enum {
    value,
    rainbow,
    other,
} Mode;
const char *modeName[] = {
        "value",
        "rainbow",
        "other",
};

typedef enum {
    mode,
    speed,
    hue,
    r,
    g,
    b,
    none
} MainMenu;
const char *menuName[] = {
        "mode",
        "speed",
        "hue",
        "r",
        "g",
        "b",
        "none",
};

typedef enum {
    right,
    left,
    confirm
} Action;

typedef struct State {
    Mode mode = Mode::value;
    MainMenu menu = MainMenu::none;
    MainMenu menuHover = MainMenu::mode;
    uint8_t valueHue = 0;
    uint8_t valueR = 0;
    uint8_t valueG = 0;
    uint8_t valueB = 0;
    uint8_t rainbowSpeed = 0;
    bool hasChanged = true;
} State;

State state;

uint8_t getMenuValue(MainMenu menu) {
    switch (menu) {
        case r:
            return state.valueR;
        case g:
            return state.valueG;
        case b:
            return state.valueB;
        case hue:
            return state.valueHue;
        case speed:
            return state.rainbowSpeed;
    }
    return 0;
}

const MainMenu modeMenus[3][MainMenu::none - 1] = {
        {MainMenu::mode, MainMenu::hue,   MainMenu::r,    MainMenu::g,    MainMenu::b},
        {MainMenu::mode, MainMenu::speed, MainMenu::none, MainMenu::none, MainMenu::none},
        {MainMenu::mode, MainMenu::speed, MainMenu::none, MainMenu::none, MainMenu::none},
};

MainMenu maxMenu() {
    auto menus = modeMenus[state.menu];
    for (int i = 0; i <= MainMenu::b; ++i) {
        MainMenu mode = menus[i];
        if (mode == none) {
            return menus[i - 1];
        }
    }
    return MainMenu::b;
}


char strTmp[16] = {0};
void display() {
    sprintf(strTmp, "%s%s ", state.menuHover == mode ? "-" : " ", menuName[mode]);
    u8x8.drawString(0, 0, strTmp);
    sprintf(strTmp, " %8s", modeName[state.mode]);
    if (state.menu == MainMenu::mode) u8x8.inverse();
    u8x8.drawString(6, 0, strTmp);
    if (state.menu == MainMenu::mode) u8x8.noInverse();

    auto menus = modeMenus[state.mode];
    for (int i = 1; i < MainMenu::b; ++i) {
        auto m = menus[i];
        const int line = (i + 1) * 1;
        if (m != MainMenu::none) {
            auto hovered = state.menuHover == m;
            sprintf(strTmp, "%s%-5s", hovered ? "-" : " ", menuName[m]);
            u8x8.drawString(0, line, strTmp);
            if (state.menu == m) u8x8.inverse();
            sprintf(strTmp, "%3d", getMenuValue(m));
            u8x8.drawString(6, line, strTmp);
            if (state.menu == m) u8x8.noInverse();
        } else {
            sprintf(strTmp, "%10s", " ");
            u8x8.drawString(0, line, strTmp);
        }
    }
}

uint8_t next(uint8_t i, uint8_t max) {
    return i == max ? 0 : i + 1;
}

uint8_t prev(uint8_t i, uint8_t max) {
    return i == 0 ? max : i - 1;
}

void hoverNext() {
    Serial.println(state.menuHover);
    state.menuHover = MainMenu(next(state.menuHover, maxMenu()));
}

void actualizeHue() { state.valueHue = rgb2hsv_approximate(CRGB(state.valueR, state.valueG, state.valueB)).hue; }

void actualizeRGB() {
    static CRGB tmp;
    hsv2rgb_rainbow(CHSV(state.valueHue, 1, 1), tmp);
    state.valueR = tmp.r;
    state.valueG = tmp.g;
    state.valueB = tmp.b;
}

void hoverPrev() { state.menuHover = MainMenu(prev(state.menuHover, maxMenu())); }

void modeNext() { state.mode = Mode(next(state.mode, Mode::other)); }

void modePrev() { state.mode = Mode(prev(state.mode, Mode::other)); }

void hueNext() {
    state.valueHue = next(state.valueHue, 255);
    actualizeRGB();
}

void huePrev() {
    state.valueHue = prev(state.valueHue, 255);
    actualizeRGB();
}

void rNext() {
    state.valueR = next(state.valueR, 255);
    actualizeHue();
}

void rPrev() {
    state.valueR = prev(state.valueR, 255);
    actualizeHue();
}

void gNext() {
    state.valueG = next(state.valueG, 255);
    actualizeHue();
}

void gPrev() {
    state.valueG = prev(state.valueG, 255);
    actualizeHue();
}

void bNext() {
    state.valueB = next(state.valueB, 255);
    actualizeHue();
}

void bPrev() {
    state.valueB = prev(state.valueB, 255);
    actualizeHue();
}

void handleAction(Action action) {
    if (action == Action::right) {
        if (state.menu == none) {
            hoverNext();
        } else if (state.menu == MainMenu::mode) {
            modeNext();
        } else if (state.menu == MainMenu::r) {
            rNext();
        } else if (state.menu == MainMenu::g) {
            gNext();
        } else if (state.menu == MainMenu::b) {
            bNext();
        } else if (state.menu == MainMenu::hue) {
            hueNext();
        }
        state.hasChanged = true;
    } else if (action == Action::left) {
        if (state.menu == none) {
            hoverPrev();
        } else if (state.menu == MainMenu::mode) {
            modePrev();
        } else if (state.menu == MainMenu::r) {
            rPrev();
        } else if (state.menu == MainMenu::g) {
            gPrev();
        } else if (state.menu == MainMenu::b) {
            bPrev();
        } else if (state.menu == MainMenu::hue) {
            huePrev();
        }
        state.hasChanged = true;
    } else if (action == Action::confirm) {
        if (state.menu == MainMenu::none) {
            state.menu = state.menuHover;
        } else {
            state.menu = MainMenu::none;
        }
        state.hasChanged = true;
    }
}

void led() {
    if (state.mode == value) {
        FastLED.showColor(CRGB(state.valueR, state.valueG, state.valueB));
    }
}

void setup(void) {
    Serial.begin(9600);
    u8x8.begin();
    FastLED.addLeds<WS2812, ledPin, GRB>(leds, NUM_LEDS);
    u8x8.setFont(u8x8_font_chroma48medium8_r);
}

void loop(void) {
    enc.tick();
    if (enc.right()) handleAction(Action::right);
    if (enc.left()) handleAction(Action::left);
    if (enc.click()) handleAction(Action::confirm);

    if (state.hasChanged) {
        display();
        led();
        state.hasChanged = false;
    }
}