#include <stdlib.h>

#include "eve.h"
#include "eve_font.h"

void eve_font_init(EVEFont *font, uint8_t font_id) {
    uint32_t p;

    p = eve_read32(EVE_ROM_FONT_ADDR);
    p += (148 * (font_id - 16));
    font->id = font_id;
    font->w = eve_read32(p + 136);
    font->h = eve_read32(p + 140);
    eve_readb(p, font->w_ch, 128);
}

int eve_font_ch_w(EVEFont *font, ucp_t ch) {
    if (ch < 128) return font->w_ch[ch];
    return EVE_ERR;
}

static int font_str_w(EVEFont *font, utf8_t *str, int *str_w, size_t *str_len) {
    uint16_t r = 0;
    size_t len = 0;
    ucp_t ch;
    int ch_w;
    int ch_l;

    while (str[len]) {
        ch_l = utf8_dec(str + len, &ch);
        ch_w = eve_font_ch_w(font, ch);
        if (ch_w < 0) {
            if (str_w) *str_w = r;
            if (str_len) *str_len = len;
            return EVE_ERR;
        }
        r += ch_w;
        len += ch_l;
    }

    if (str_w) *str_w = r;
    if (str_len) *str_len = len;
    return EVE_OK;
}

static int font_buf_w(EVEFont *font, utf8_t *buf, size_t buf_len, int *str_w, size_t *str_len) {
    uint16_t r = 0;
    size_t len = 0;
    ucp_t ch;
    int ch_w;
    int ch_l;

    while (len < buf_len) {
        ch_l = utf8_dec(buf + len, &ch);
        ch_w = eve_font_ch_w(font, ch);
        if (ch_w < 0) {
            if (str_w) *str_w = r;
            if (str_len) *str_len = len;
            return EVE_ERR;
        }
        r += ch_w;
        len += ch_l;
    }

    if (str_w) *str_w = r;
    if (str_len) *str_len = len;
    return EVE_OK;
}

int eve_font_verify(EVEFont *font, utf8_t *str, int *str_w, size_t *str_len) {
    int rv;

    rv = font_str_w(font, str, str_w, str_len);
    return rv;
}

int eve_font_str_w(EVEFont *font, utf8_t *str) {
    int str_w, rv;

    rv = font_str_w(font, str, &str_w, NULL);
    if (rv < 0) return rv;
    return str_w;
}

int eve_font_buf_w(EVEFont *font, utf8_t *str, size_t buf_len) {
    int buf_w, rv;

    rv = font_buf_w(font, str, buf_len, &buf_w, NULL);
    if (rv < 0) return rv;
    return buf_w;
}

uint8_t eve_font_h(EVEFont *font) {
    return font->h;
}