/**
 * @file wl_flash.h
 * @author xushenghao
 * @date 2024-07-22 13:57:02
 * @brief
 * @copyright Copyright (c) 2024 by xxx, All Rights Reserved.
 */
/**
 * @brief 磨损平衡算法
 *
 * 1. 初始化block_page大小和当前写入地址
 * 2. 写入数据前，检查剩余空间是否足够
 *    a. 如果足够，直接写入数据
 *    b. 如果不足够，执行以下步骤：
 *       i. 检查是否有已擦除但未使用的block_page，如果有，移动到该block_page继续写入
 *       ii. 如果没有已擦除的block_page，检查当前block_page是否已满
 *           - 如果已满，移动到下一个block_page
 *           - 在移动前，检查该block_page是否有有效数据需要迁移，如果有，则先迁移数据
 * 3. 在决定擦除新的block_page前，采用Wear Leveling算法选择最佳的block_page进行擦除
 * 4. 数据写入后，更新剩余空间大小和当前写入地址
 */

/**
 * 使用方法
 *
    #define LL_FLASH_PAGE_SIZE (2 * 1024)
    #define PVD_RESET_STORAGE_START_ADDRESS (256 * LL_FLASH_PAGE_SIZE)
    static void test_wl_flash(void)
    {
        uint32_t address = 0;
        wl_flash_t wf = {
            .wl_flag = TRUE,
            .addr = PVD_RESET_STORAGE_START_ADDRESS,
            .len = 2 * LL_FLASH_PAGE_SIZE,
            .page_size = LL_FLASH_PAGE_SIZE,
            .data_size = sizeof(device_reset_t),
            .write_gran = 8,

            .ops.srand = board_srand,
            .ops.read = flash_read,
            .ops.write = flash_write,
            .ops.erase_page = flash_erase_page,
        };
        wl_flash_init(&wf);
        wl_flash_erase(&wf);
        address = wl_flash_get_current_address(&wf);

        device_reset_t power_on;
        power_on.flag = PVD_RESET_FLAG;

        // 一页2048/16 = 128个数据,2页 = 256个数据，i=255时数据从头开始
        for (uint16_t i = 0; i < 1000; i++)
        {
            wl_flash_write(&wf, (uint8_t *)&power_on, sizeof(device_reset_t));
            wl_flash_set_next_address(&wf);
            address = wl_flash_get_current_address(&wf);
            if (address == wf.addr)
            {
                __NOP();
            }
        }
    }
 */

#ifndef __WL_FLASH_H__
#define __WL_FLASH_H__
#include "lib.h"

typedef struct
{
    BOOL wl_flag;       // 开启平衡擦写标志
    uint32_t addr;      // Flash 起始地址
    uint32_t len;       // Flash 长度
    uint16_t page_size; // Flash 页大小 2^N
    uint16_t data_size; // 数据大小
    /* write minimum granularity, unit: byte.
       1(stm32f2/f4)/ 4(stm32f1)/ 8(stm32l4)
       0 will not take effect. */
    uint8_t write_gran;
    struct
    {
        void (*srand)(void); // 随机数种子
        BOOL(*read)
        (uint32_t addr, uint8_t *buf, uint16_t size);
        BOOL(*write)
        (uint32_t addr, const uint8_t *buf, uint16_t size);
        BOOL(*erase_page)
        (uint32_t page);
    } ops;

    struct
    {
        uint32_t current_address; // 当前准备写入的地址
        uint16_t residue_size;    // 剩余可写大小
        uint16_t start_page;      // 起始页
        uint16_t page_total;      // 总页数
        uint16_t block_page;      // 擦除块大小
    } private;
} wl_flash_t;

extern void wl_flash_init(wl_flash_t *cfg);                                     ///< 初始化 Flash 磨损平衡算法
extern uint32_t wl_flash_get_current_address(wl_flash_t *cfg);                  ///< 获取当前写入地址
extern void wl_flash_set_next_address(wl_flash_t *cfg);                         ///< 设置下一个写入地址，下一个写入区域会被擦除
extern void wl_flash_set_current_address(wl_flash_t *cfg, uint32_t address);    ///< 设置当前写入地址
extern void wl_flash_erase(wl_flash_t *cfg);                                    ///< 擦除 Flash, 如果开启了平衡擦写标志, 则会随机分配写入地址
extern BOOL wl_flash_write(wl_flash_t *cfg, const uint8_t *buf, uint16_t size); ///< 写入 Flash
extern BOOL wl_flash_read(wl_flash_t *cfg, uint8_t *buf, uint16_t size);        ///< 读取 Flash
#endif                                                                          // __WL_FLASH_H__