/*
 * Copyright 2017, Data61, CSIRO (ABN 41 687 119 230)
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

/* CAmkES provides a generated header that prototypes all the relevant generated
 * symbols.
 */
#include <camkes.h>
#include <camkes/io.h>

#include <assert.h>
#include <keyboard/codes.h>
#include <keyboard/keyboard.h>
#include <ringbuffer/ringbuffer.h>
#include <utils/util.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>

static ps_io_port_ops_t io_port_ops;

static uint8_t in8(uint16_t port)
{
    uint32_t result = 0;
    int error = ps_io_port_in(&io_port_ops, port, IOSIZE_8, &result);
    if (error) {
        return 0;
    }
    return (uint8_t) result;
}

static void out8(uint16_t port, uint8_t value)
{
    ps_io_port_out(&io_port_ops, port, IOSIZE_8, value);
}

int run(void)
{
    int error = camkes_io_port_ops(&io_port_ops);
    assert(!error);

    sel4keyboard_init(0, in8, out8);

    ringbuffer_t *output = rb_new((void *)char_out, sizeof(*char_out));
    if (output == NULL) {
        abort();
    }

    /* Take each received character and pass it on to the switch. */
    while (true) {
        int c;

        /* do basic tracking of multi byte sequences */
        static int escape_code = 0;
        static int escape_state = 0;
        static int break_code = 0;

        while (!sel4keyboard_get_scancode(&c));

        /* first parse escape codes etc */
        switch (c) {
        case 0xf0:
            break_code = 0xf0;
            continue;
        case 0xe0:
        case 0xe1:
            escape_code = c;
            escape_state = 0;
            continue;
        default:
            /* need to do actual parsing */
            switch (escape_code) {
            case 0xe1:
                /* need to ignore two scancodes */
                escape_state++;
                if (escape_state == 2) {
                    escape_code = 0;
                    break_code = 0;
                }
                continue;
            case 0xe0:
                /* key down */
                break_code = 0;
                escape_code = 0;
                continue;
            default:
                if (!break_code) {
                    break_code = 0;
                    escape_code = 0;
                    continue;
                }
                /* key up */
                break_code = 0;
                escape_code = 0;
                break;
            }
            break;
        }

        char c1 = sel4keyboard_code_to_char(c);
        if (c1 != 0) {
            rb_transmit_byte(output, (unsigned char)c1);
        }
    }

    return 0;
}