/*
 * 模块名称：LCD 绘图模块
 * 模块功能：提供字符、字符串（中英文混合）、线条、矩形、圆形等图形绘制
 * 适用平台：STM32F103C8T6 + ST7735S + 底层 st7735s.c
 * 作者：王建锋
 * 创建日期：2026-07-14
 * 修改记录：
 *     2026-07-14  王建锋  从 st7735s.c 拆分
 */

#include "lcd.h"
#include "lcd_data.h"
#include "hz16_data.h"
#include <string.h>

/*
 * 函数功能：UTF-8字符转Unicode（辅助）
 * 入口参数：str - UTF-8字符串指针（会被推进到下一字符起始）
 * 返回值：Unicode码点，或0（异常/结束）
 * 函数说明：支持1~3字节UTF-8，推进str
 */
static uint16_t utf8_to_unicode(const char **str)
{
    uint16_t code;
    uint8_t c;

    c = (uint8_t)(**str);
    if (c == 0) {
        return 0;
    }

    if (c < 0x80) {
        code = c;
        (*str)++;
    } else if ((c & 0xE0) == 0xC0) {
        code = c & 0x1F;
        (*str)++;
        code = (code << 6) | ((uint8_t)(**str) & 0x3F);
        (*str)++;
    } else if ((c & 0xF0) == 0xE0) {
        code = c & 0x0F;
        (*str)++;
        code = (code << 6) | ((uint8_t)(**str) & 0x3F);
        (*str)++;
        code = (code << 6) | ((uint8_t)(**str) & 0x3F);
        (*str)++;
    } else {
        (*str)++;
        return 0;
    }
    return code;
}

/*
 * 函数功能：显示一个8x16 ASCII字符
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           ch - 字符 (ASCII 32-126)
 *           color - 字符颜色 (RGB565)
 *           bg_color - 背景颜色 (RGB565)
 * 返回值：无
 * 函数说明：框选8x16区域→遍历字模bit→发送color或bg_color
 */
void lcd_draw_char(uint16_t x, uint16_t y, char ch, uint16_t color, uint16_t bg_color)
{
    uint16_t i;
    uint16_t j;
    uint8_t line;

    if (ch < 32 || ch > 126) {
        ch = ' ';
    }

    st7735s_set_window(x, y, x + 7, y + 15);

    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(LCD_DC_PORT, LCD_DC_PIN, GPIO_PIN_SET);
    for (i = 0; i < 16; i++) {
        line = LCD_F8x16[ch - 32][i];
        for (j = 0; j < 8; j++) {
            if (line & 0x80) {
                st7735s_spi_write_byte((uint8_t)(color >> 8));
                st7735s_spi_write_byte((uint8_t)(color & 0xFF));
            } else {
                st7735s_spi_write_byte((uint8_t)(bg_color >> 8));
                st7735s_spi_write_byte((uint8_t)(bg_color & 0xFF));
            }
            line <<= 1;
        }
    }
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_SET);
}

/*
 * 函数功能：显示字符串
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           str - 字符串指针
 *           color - 字符颜色 (RGB565)
 *           bg_color - 背景颜色 (RGB565)
 * 返回值：无
 * 函数说明：连续显示字符串，自动换行
 */
void lcd_draw_string(uint16_t x, uint16_t y, const char *str, uint16_t color, uint16_t bg_color)
{
    uint16_t start_x = x;

    while (*str != '\0') {
        if (*str == '\n') {
            y += FONT_HEIGHT_16;
            x = start_x;
            str++;
            continue;
        }
        if (x + 8 > s_lcd_width) {
            y += FONT_HEIGHT_16;
            x = start_x;
        }
        if (y + 16 > s_lcd_height) {
            break;
        }
        lcd_draw_char(x, y, *str, color, bg_color);
        x += FONT_WIDTH_8;
        str++;
    }
}

/*
 * 函数功能：显示一个6x8 ASCII字符
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           ch - 字符 (ASCII 32-126)
 *           color - 字符颜色 (RGB565)
 *           bg_color - 背景颜色 (RGB565)
 * 返回值：无
 * 函数说明：LCD_F6x8为列式存储（每字节一列，bit0=顶行，bit7=底行）
 *          框选6x8区域→逐行逐列取bit→发送color或bg_color
 */
void lcd_draw_char_6x8(uint16_t x, uint16_t y, char ch, uint16_t color, uint16_t bg_color)
{
    uint8_t row;
    uint8_t col;
    uint8_t col_data;

    if (ch < 32 || ch > 126) {
        ch = ' ';
    }

    st7735s_set_window(x, y, x + 5, y + 7);

    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(LCD_DC_PORT, LCD_DC_PIN, GPIO_PIN_SET);

    for (row = 0; row < 8; row++) {
        for (col = 0; col < 6; col++) {
            col_data = LCD_F6x8[ch - 32][col];
            if (col_data & (1 << row)) {
                st7735s_spi_write_byte((uint8_t)(color >> 8));
                st7735s_spi_write_byte((uint8_t)(color & 0xFF));
            } else {
                st7735s_spi_write_byte((uint8_t)(bg_color >> 8));
                st7735s_spi_write_byte((uint8_t)(bg_color & 0xFF));
            }
        }
    }
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_SET);
}

/*
 * 函数功能：显示字符串（6x8字体）
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           str - 字符串指针
 *           color - 字符颜色 (RGB565)
 *           bg_color - 背景颜色 (RGB565)
 * 返回值：无
 * 函数说明：连续显示6x8字符，自动换行
 */
void lcd_draw_string_6x8(uint16_t x, uint16_t y, const char *str, uint16_t color, uint16_t bg_color)
{
    uint16_t start_x = x;

    while (*str != '\0') {
        if (*str == '\n') {
            y += FONT_HEIGHT_8;
            x = start_x;
            str++;
            continue;
        }
        if (x + FONT_WIDTH_6 > s_lcd_width) {
            y += FONT_HEIGHT_8;
            x = start_x;
        }
        if (y + FONT_HEIGHT_8 > s_lcd_height) {
            break;
        }
        lcd_draw_char_6x8(x, y, *str, color, bg_color);
        x += FONT_WIDTH_6;
        str++;
    }
}

/*
 * 函数功能：显示一个16x16 CJK汉字
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           unicode - Unicode码点 (如 0x4E00="一")
 *           color - 字符颜色 (RGB565)
 *           bg_color - 背景颜色 (RGB565)
 * 返回值：无
 * 函数说明：框选16x16区域→遍历字模bit→发送color或bg_color
 */
void lcd_draw_chinese(uint16_t x, uint16_t y, uint16_t unicode,
                      uint16_t color, uint16_t bg_color)
{
    uint16_t i;
    uint16_t j;
    uint8_t k;
    uint8_t line;
    const uint8_t *bitmap;

    bitmap = cjk_get_bitmap(unicode);
    if (bitmap == NULL) {
        return;
    }

    st7735s_set_window(x, y, x + CJK_WIDTH - 1, y + CJK_HEIGHT - 1);

    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(LCD_DC_PORT, LCD_DC_PIN, GPIO_PIN_SET);
    for (i = 0; i < CJK_HEIGHT; i++) {
        for (j = 0; j < CJK_WIDTH / 8; j++) {
            line = bitmap[i * (CJK_WIDTH / 8) + j];
            for (k = 0; k < 8; k++) {
                if (line & 0x80) {
                    st7735s_spi_write_byte((uint8_t)(color >> 8));
                    st7735s_spi_write_byte((uint8_t)(color & 0xFF));
                } else {
                    st7735s_spi_write_byte((uint8_t)(bg_color >> 8));
                    st7735s_spi_write_byte((uint8_t)(bg_color & 0xFF));
                }
                line <<= 1;
            }
        }
    }
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_SET);
}

/*
 * 函数功能：显示UTF-8字符串（自动中英文混合）
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           str - UTF-8字符串指针
 *           color - 字符颜色 (RGB565)
 *           bg_color - 背景颜色 (RGB565)
 * 返回值：无
 * 函数说明：自动识别ASCII(8x16)和CJK(16x16)，自动换行
 */
void lcd_draw_chinese_string(uint16_t x, uint16_t y,
                             const char *str,
                             uint16_t color, uint16_t bg_color)
{
    uint16_t start_x = x;

    while (*str != '\0') {
        uint8_t c = (uint8_t)(*str);

        if (*str == '\n') {
            y += CJK_HEIGHT;
            x = start_x;
            str++;
            continue;
        }

        if (c < 0x80) {
            if (x + 8 > s_lcd_width) {
                y += CJK_HEIGHT;
                x = start_x;
            }
            if (y + 16 > s_lcd_height) {
                break;
            }
            lcd_draw_char(x, y, (char)c, color, bg_color);
            x += 8;
            str++;
        } else {
            const char *p = str;
            uint16_t unicode = utf8_to_unicode(&p);
            if (unicode == 0) {
                str = p;
                continue;
            }
            if (x + CJK_WIDTH > s_lcd_width) {
                y += CJK_HEIGHT;
                x = start_x;
            }
            if (y + CJK_HEIGHT > s_lcd_height) {
                break;
            }
            lcd_draw_chinese(x, y, unicode, color, bg_color);
            x += CJK_WIDTH;
            str = p;
        }
    }
}

/*
 * 函数功能：画线（Bresenham算法）
 * 入口参数：x1 - 起始列
 *           y1 - 起始行
 *           x2 - 结束列
 *           y2 - 结束行
 *           color - 颜色 (RGB565)
 * 返回值：无
 */
void lcd_draw_line(uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2, uint16_t color)
{
    int16_t dx;
    int16_t dy;
    int16_t sx;
    int16_t sy;
    int16_t err;
    int16_t e2;
    int16_t x = (int16_t)x1;
    int16_t y = (int16_t)y1;

    dx = (x1 < x2) ? (int16_t)(x2 - x1) : (int16_t)(x1 - x2);
    dy = (y1 < y2) ? (int16_t)(y2 - y1) : (int16_t)(y1 - y2);
    sx = (x1 < x2) ? 1 : -1;
    sy = (y1 < y2) ? 1 : -1;
    err = dx - dy;

    while (1) {
        st7735s_draw_pixel((uint16_t)x, (uint16_t)y, color);
        if (x == (int16_t)x2 && y == (int16_t)y2) {
            break;
        }
        e2 = 2 * err;
        if (e2 > -dy) {
            err -= dy;
            x += sx;
        }
        if (e2 < dx) {
            err += dx;
            y += sy;
        }
    }
}

/*
 * 函数功能：画空心矩形
 * 入口参数：x - 左上角列
 *           y - 左上角行
 *           width - 宽度
 *           height - 高度
 *           color - 颜色 (RGB565)
 * 返回值：无
 */
void lcd_draw_rect(uint16_t x, uint16_t y, uint16_t width, uint16_t height, uint16_t color)
{
    uint16_t x2 = x + width - 1;
    uint16_t y2 = y + height - 1;

    lcd_draw_line(x, y, x2, y, color);
    lcd_draw_line(x, y, x, y2, color);
    lcd_draw_line(x2, y, x2, y2, color);
    lcd_draw_line(x, y2, x2, y2, color);
}

/*
 * 函数功能：画空心圆（Bresenham算法）
 * 入口参数：x0 - 圆心列
 *           y0 - 圆心行
 *           radius - 半径
 *           color - 颜色 (RGB565)
 * 返回值：无
 */
void lcd_draw_circle(uint16_t x0, uint16_t y0, uint16_t radius, uint16_t color)
{
    int16_t x = 0;
    int16_t y = (int16_t)radius;
    int16_t err = 1 - (int16_t)radius;
    int16_t xc = (int16_t)x0;
    int16_t yc = (int16_t)y0;

    while (x <= y) {
        st7735s_draw_pixel((uint16_t)(xc + x), (uint16_t)(yc + y), color);
        st7735s_draw_pixel((uint16_t)(xc - x), (uint16_t)(yc + y), color);
        st7735s_draw_pixel((uint16_t)(xc + x), (uint16_t)(yc - y), color);
        st7735s_draw_pixel((uint16_t)(xc - x), (uint16_t)(yc - y), color);
        st7735s_draw_pixel((uint16_t)(xc + y), (uint16_t)(yc + x), color);
        st7735s_draw_pixel((uint16_t)(xc - y), (uint16_t)(yc + x), color);
        st7735s_draw_pixel((uint16_t)(xc + y), (uint16_t)(yc - x), color);
        st7735s_draw_pixel((uint16_t)(xc - y), (uint16_t)(yc - x), color);
        x++;
        if (err < 0) {
            err += 2 * x + 1;
        } else {
            y--;
            err += 2 * (x - y) + 1;
        }
    }
}