//
// Created by steven on 11/14/2024.
//

#include <time.h>
#include <stdlib.h>
#include <signal.h>
#include <gpiod.h>
#include <string.h>

#include "../libs/go_p2fa.h"
#include "../libs/e-Paper/EPD_2in13_V4.h"
#include "../libs/GUI/GUI_Paint.h"
#include "../libs/GUI/GUI_BMPfile.h"
#include "../libs/Config/Debug.h"

#define GPIO_CHIP "/dev/gpiochip0"
#define DEBOUNCE_TIME_MS 50

// GPIO Pins
#define BUTTON_UP 13
#define BUTTON_DOWN 19
#define BUTTON_LEFT 12
#define BUTTON_RIGHT 16
#define BUTTON_SELECT 27
#define BUTTON_ALT 22
#define BUTTON_BACK 6
#define BUTTON_POWER 20

typedef struct {
    int gpio_pin;
    int key_code;
} ButtonMap;

ButtonMap button_map[] = {
    {BUTTON_UP, 'u'},
    {BUTTON_DOWN, 'd'},
    {BUTTON_LEFT, 'l'},
    {BUTTON_RIGHT, 'r'},
    {BUTTON_SELECT, 's'},
    {BUTTON_ALT, 'a'},
    {BUTTON_BACK, 'b'},
    {BUTTON_POWER, 'p'},
};

#define NUM_BUTTONS 8

struct gpiod_chip *chip;
struct gpiod_line_bulk lines;
struct gpiod_line *line_pointers[NUM_BUTTONS];

int last_button_state[NUM_BUTTONS] = {0};
struct timespec last_press_time[NUM_BUTTONS];

void closeP2FA() {
    EPD_2in13_V4_Init();
    EPD_2in13_V4_Clear();
    EPD_2in13_V4_Sleep();
    DEV_Delay_ms(2000); // Important, at least 2s
    DEV_Module_Exit();

    for (int i = 0; i < NUM_BUTTONS; i++) {
        gpiod_line_release(line_pointers[i]);
    }
    gpiod_chip_close(chip);
}

void Handler(int sigNum) {
    Debug("Caught signal %d\n", sigNum);
    closeP2FA();
    exit(0);
}

int computeWidth(char* text, sFONT *font) {
    return font->Width * strlen(text);
}

int readButtons() {
    for (int i = 0; i < NUM_BUTTONS; i++) {
        int value = gpiod_line_get_value(line_pointers[i]);
        if (value < 0) {
            perror("Failed to read GPIO value");
            continue;
        }

        // Debounce logic
        struct timespec now;
        clock_gettime(CLOCK_MONOTONIC, &now);
        long elapsed_ms = (now.tv_sec - last_press_time[i].tv_sec) * 1000 +
                          (now.tv_nsec - last_press_time[i].tv_nsec) / 1000000;

        if (value == 1 && last_button_state[i] == 0 && elapsed_ms > DEBOUNCE_TIME_MS) {
            last_button_state[i] = 1;
            last_press_time[i] = now;
            return button_map[i].key_code;
        }
        if (value == 0) {
            last_button_state[i] = 0;
        }
    }

    return -1;  // No button press detected
}

int getBtn() {
    while (1) {
        int key = readButtons();
        if (key != -1) {
            return key;
        }
        // Add a short delay to reduce CPU usage
        DEV_Delay_ms(10);
    }
}

//TODO Put display to sleep after so many refreshes
void code(UWORD *blackImage, char* confName) {
    //int ch;
    while(1) {
        // ch = getch();
        // if (ch != ERR) {
        //     if (ch == 'q') break;
        //     Debug("Key Pressed: %c\n", ch);
        // }

        Paint_NewImage(blackImage, EPD_2in13_V4_WIDTH, EPD_2in13_V4_HEIGHT, 90, WHITE);
        EPD_2in13_V4_Init();
        Paint_SelectImage(blackImage);
        Paint_Clear(WHITE);

        GoString confStr = {confName, strlen(confName)};
        const char *code = getCode(confStr);
        int codeLength = strlen(code);
        if (codeLength <= 6) {
            Paint_DrawString(5, 20, code, &Font65, WHITE, BLACK);
        } else if (codeLength > 8) {
            Paint_DrawString(5, 20, code, &Font40, WHITE, BLACK);
        } else if (codeLength > 6) {
            Paint_DrawString(5, 20, code, &Font56, WHITE, BLACK);
        }
        Paint_DrawString(8, 5, confName, &Font12, WHITE, BLACK);

        Paint_DrawRectangle(10, 114, 240, 94, BLACK, DOT_PIXEL_1X1, DRAW_FILL_EMPTY);
        EPD_2in13_V4_Display_Base(blackImage);

        Paint_NewImage(blackImage, EPD_2in13_V4_WIDTH, EPD_2in13_V4_HEIGHT, 90, WHITE);
        Paint_SelectImage(blackImage);

        clock_t startTime;
        clock_t endTime;
        int elapsedTime;
        int progBarCurrentIndex = 11;
        int progBarEndIndex;
        int lastI = 30 * 1000;
        for (int i = getTimeRemainingMS(30);; i = getTimeRemainingMS(30)) {
            //ch = getch();
            //if (ch != ERR) {
            //    if (ch == 'q') return;
            //}
            if (i > lastI) break;
            startTime = clock();

            double percentLeft = (double) i / (double) (30 * 1000);
            progBarEndIndex = 228 - (int) (228 * percentLeft);
            Paint_ClearWindows(progBarCurrentIndex, 113, progBarEndIndex, 95, WHITE);
            int line = 15;
            while (progBarCurrentIndex < progBarEndIndex) {
                Paint_DrawLine(progBarCurrentIndex, 113, progBarCurrentIndex, 95, BLACK, DOT_PIXEL_1X1,
                               LINE_STYLE_SOLID);
                ++progBarCurrentIndex;
                ++line;
                if (line == 21) line = 15;
            }
            EPD_2in13_V4_Display_Partial(blackImage);
            endTime = clock();
            elapsedTime = (int) ((endTime - startTime) / CLOCKS_PER_SEC);
            if (elapsedTime < 1000) {
                DEV_Delay_ms(1000 - (elapsedTime * 1000));
            }
            lastI = i;
        }
    }
}

void config(UWORD *blackImage, char* configName) {
    GoString goConfName = { configName, strlen(configName) };
    struct getConfigLines_return configLinesReturn = getConfigLines(goConfName);
    int length = configLinesReturn.r1;
    char** configLines = configLinesReturn.r0;
    if (configLines == NULL || length == -1) {
        Debug("Config not found\n");
        return;
    }

    Paint_NewImage(blackImage, EPD_2in13_V4_WIDTH, EPD_2in13_V4_HEIGHT, 90, WHITE);
    EPD_2in13_V4_Init();
    Paint_SelectImage(blackImage);
    Paint_Clear(WHITE);

    for (int i = 0; i < length; i++) {
        Paint_DrawString(5, 5 + (i * 16), configLines[i], &Font12, WHITE, BLACK);
    }

    EPD_2in13_V4_Display(blackImage);

    //int ch = getch();
}

void drawTotpHome(UWORD *blackImage, char** configNames, int *length) {
    Paint_NewImage(blackImage, EPD_2in13_V4_WIDTH, EPD_2in13_V4_HEIGHT, 0, WHITE);
    Paint_SelectImage(blackImage);
    Paint_Clear(WHITE);
    for (int j = 0; j < *length; j++) {
        if (configNames[j] == NULL) {
            Debug("Null Config: %d\n", j);
        }
        Paint_DrawString(5, 5 + j * 20, configNames[j], &Font12, WHITE, BLACK);
    }
    EPD_2in13_V4_Display_Base(blackImage);
    Paint_NewImage(blackImage, EPD_2in13_V4_WIDTH, EPD_2in13_V4_HEIGHT, 0, WHITE);
    Paint_SelectImage(blackImage);
}

void totpHome(UWORD *blackImage) {
    struct getConfigNames_return configNamesReturn = getConfigNames();
    int length = configNamesReturn.r1;
    char** configNames = configNamesReturn.r0;

    if (configNames == NULL || length == 0) {
        Debug("No configs found\n");
        return;
    }

    drawTotpHome(blackImage, configNames, &length);

    int i = 0;
    Paint_DrawString(115, 5 + (i * 20), "<", &Font12, WHITE, BLACK);
    EPD_2in13_V4_Display_Partial(blackImage);

    int ch;
    while (1) {
        //timeout(-1);
        ch = 'q'; //getch();
        if (!ch) {
            switch(ch) {
                // case KEY_UP:
                //     if (i > 0) i--;
                //     Paint_ClearWindows(115, 5 + (i + 1) * 20, 122, 17 + (i + 1) * 20, WHITE);
                //     break;
                // case KEY_DOWN:
                //     if (i < length - 1) i++;
                //     Paint_ClearWindows(115, 5 + (i - 1) * 20, 122, 17 + (i - 1) * 20, WHITE);
                //     break;
                case '\n':
                    code(blackImage, configNames[i]);
                    drawTotpHome(blackImage, configNames, &length);
                    break;
                case 'c':
                    config(blackImage, configNames[i]);
                    drawTotpHome(blackImage, configNames, &length);
                    break;
                case 'q':
                    return;
            }
        }

        Paint_DrawString(115, 5 + (i * 20), "<", &Font12, WHITE, BLACK);
        EPD_2in13_V4_Display_Partial(blackImage);
    }

    freeCStringArray(configNames, length);

    DEV_Delay_ms(2000);
}


int drawLoop() {
    if (DEV_Module_Init() != 0) {
        return -1;
    }
    EPD_2in13_V4_Init();
    EPD_2in13_V4_Clear();

    UBYTE *blackImage;
    UWORD ImageSize = ((EPD_2in13_V4_WIDTH % 8 == 0) ? (EPD_2in13_V4_WIDTH / 8) : (EPD_2in13_V4_WIDTH / 8 + 1)) * EPD_2in13_V4_HEIGHT;
    if ((blackImage = (UBYTE *) malloc(ImageSize)) == NULL) {
        Debug("Failed to apply for black memory...\n");
        return -1;
    }

    totpHome(blackImage);

    return 0;
}

int main() {
    signal(SIGINT, Handler);
    signal(SIGTERM, Handler);

    loadConfigs();

    // Begin Init GPIO
    chip = gpiod_chip_open(GPIO_CHIP);
    if (!chip) {
        printf("Failed to open GPIO chip\n");
        exit(EXIT_FAILURE);
    }
    for (int i = 0; i < NUM_BUTTONS; i++) {
        line_pointers[i] = gpiod_chip_get_line(chip, button_map[i].gpio_pin);
        if (!line_pointers[i]) {
            printf("Failed to get GPIO line\n");
            exit(EXIT_FAILURE);
        }
        if (gpiod_line_request_input(line_pointers[i], "gpio_button") < 0) {
            printf("Failed to request input for GPIO line\n");
            gpiod_chip_close(chip);
            exit(EXIT_FAILURE);
        }
        gpiod_line_bulk_init(&lines, NUM_BUTTONS, line_pointers);
    }
    // End Init GPIO

    printf("Monitoring buttons. Press Ctrl+C to exit.\n");
    while (1) {
        printf("Button: %c\n", (char)getBtn());
    }

    //drawLoop();

    closeP2FA();
    return 0;
}