// Copyright 2020 Espressif Systems (Shanghai) Co., Ltd.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "string.h"
#include "sdkconfig.h"
#include "esp_err.h"
#include "esp_log.h"
#if CONFIG_IDF_TARGET_ESP32
#include "esp32/rom/spi_flash.h"
#elif CONFIG_IDF_TARGET_ESP32S2
#include "esp32s2/rom/spi_flash.h"
#include "esp32s2/rom/ets_sys.h"
#endif
#include "esp_rom_crc.h"
#include "esp_rom_gpio.h"
#include "esp_flash_partitions.h"
#include "bootloader_flash.h"
#include "bootloader_common.h"
#include "soc/gpio_periph.h"
#include "soc/rtc.h"
#include "soc/efuse_reg.h"
#include "hal/gpio_ll.h"
#include "esp_image_format.h"
#include "bootloader_sha.h"
#include "sys/param.h"
#include "bootloader_flash_priv.h"

#define ESP_PARTITION_HASH_LEN 32 /* SHA-256 digest length */

static const char* TAG = "boot_comm";

uint32_t bootloader_common_ota_select_crc(const esp_ota_select_entry_t *s)
{
    return esp_rom_crc32_le(UINT32_MAX, (uint8_t*)&s->ota_seq, 4);
}

bool bootloader_common_ota_select_invalid(const esp_ota_select_entry_t *s)
{
    return s->ota_seq == UINT32_MAX || s->ota_state == ESP_OTA_IMG_INVALID || s->ota_state == ESP_OTA_IMG_ABORTED;
}

bool bootloader_common_ota_select_valid(const esp_ota_select_entry_t *s)
{
    return bootloader_common_ota_select_invalid(s) == false && s->crc == bootloader_common_ota_select_crc(s);
}

int bootloader_common_get_active_otadata(esp_ota_select_entry_t *two_otadata)
{
    if (two_otadata == NULL) {
        return -1;
    }
    bool valid_two_otadata[2];
    valid_two_otadata[0] = bootloader_common_ota_select_valid(&two_otadata[0]);
    valid_two_otadata[1] = bootloader_common_ota_select_valid(&two_otadata[1]);
    return bootloader_common_select_otadata(two_otadata, valid_two_otadata, true);
}

esp_err_t bootloader_common_check_chip_validity(const esp_image_header_t* img_hdr, esp_image_type type)
{
    esp_err_t err = ESP_OK;
    esp_chip_id_t chip_id = CONFIG_IDF_FIRMWARE_CHIP_ID;
    if (chip_id != img_hdr->chip_id) {
        ESP_LOGE(TAG, "mismatch chip ID, expected %d, found %d", chip_id, img_hdr->chip_id);
        err = ESP_FAIL;
    }
    uint8_t revision = bootloader_common_get_chip_revision();
    if (revision < img_hdr->min_chip_rev) {
        ESP_LOGE(TAG, "can't run on lower chip revision, expected %d, found %d", revision, img_hdr->min_chip_rev);
        err = ESP_FAIL;
    } else if (revision != img_hdr->min_chip_rev) {
#ifdef BOOTLOADER_BUILD
        ESP_LOGI(TAG, "chip revision: %d, min. %s chip revision: %d", revision, type == ESP_IMAGE_BOOTLOADER ? "bootloader" : "application", img_hdr->min_chip_rev);
#endif
    }
    return err;
}

int bootloader_common_select_otadata(const esp_ota_select_entry_t *two_otadata, bool *valid_two_otadata, bool max)
{
    if (two_otadata == NULL || valid_two_otadata == NULL) {
        return -1;
    }
    int active_otadata = -1;
    if (valid_two_otadata[0] && valid_two_otadata[1]) {
        int condition = (max == true) ? MAX(two_otadata[0].ota_seq, two_otadata[1].ota_seq) : MIN(two_otadata[0].ota_seq, two_otadata[1].ota_seq);
        if (condition == two_otadata[0].ota_seq) {
            active_otadata = 0;
        } else {
            active_otadata = 1;
        }
        ESP_LOGD(TAG, "Both OTA copies are valid");
    } else {
        for (int i = 0; i < 2; ++i) {
            if (valid_two_otadata[i]) {
                active_otadata = i;
                ESP_LOGD(TAG, "Only otadata[%d] is valid", i);
                break;
            }
        }
    }
    return active_otadata;
}

esp_err_t bootloader_common_get_partition_description(const esp_partition_pos_t *partition, esp_app_desc_t *app_desc)
{
    if (partition == NULL || app_desc == NULL || partition->offset == 0) {
        return ESP_ERR_INVALID_ARG;
    }

    const uint32_t app_desc_offset = sizeof(esp_image_header_t) + sizeof(esp_image_segment_header_t);
    const uint32_t mmap_size = app_desc_offset + sizeof(esp_app_desc_t);
    const uint8_t *image = bootloader_mmap(partition->offset, mmap_size);
    if (image == NULL) {
        ESP_LOGE(TAG, "bootloader_mmap(0x%x, 0x%x) failed", partition->offset, mmap_size);
        return ESP_FAIL;
    }

    memcpy(app_desc, image + app_desc_offset, sizeof(esp_app_desc_t));
    bootloader_munmap(image);

    if (app_desc->magic_word != ESP_APP_DESC_MAGIC_WORD) {
        return ESP_ERR_NOT_FOUND;
    }

    return ESP_OK;
}

#if defined( CONFIG_BOOTLOADER_SKIP_VALIDATE_IN_DEEP_SLEEP ) || defined( CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC )

rtc_retain_mem_t *const rtc_retain_mem = (rtc_retain_mem_t *)(SOC_RTC_DRAM_HIGH - sizeof(rtc_retain_mem_t));

static bool check_rtc_retain_mem(void)
{
    return esp_rom_crc32_le(UINT32_MAX, (uint8_t*)rtc_retain_mem, sizeof(rtc_retain_mem_t) - sizeof(rtc_retain_mem->crc)) == rtc_retain_mem->crc && rtc_retain_mem->crc != UINT32_MAX;
}

static void update_rtc_retain_mem_crc(void)
{
    rtc_retain_mem->crc = esp_rom_crc32_le(UINT32_MAX, (uint8_t*)rtc_retain_mem, sizeof(rtc_retain_mem_t) - sizeof(rtc_retain_mem->crc));
}

void bootloader_common_reset_rtc_retain_mem(void)
{
    memset(rtc_retain_mem, 0, sizeof(rtc_retain_mem_t));
}

uint16_t bootloader_common_get_rtc_retain_mem_reboot_counter(void)
{
    if (check_rtc_retain_mem()) {
        return rtc_retain_mem->reboot_counter;
    }
    return 0;
}

esp_partition_pos_t* bootloader_common_get_rtc_retain_mem_partition(void)
{
    if (check_rtc_retain_mem()) {
        return &rtc_retain_mem->partition;
    }
    return NULL;
}

void bootloader_common_update_rtc_retain_mem(esp_partition_pos_t* partition, bool reboot_counter)
{
    if (reboot_counter) {
        if (!check_rtc_retain_mem()) {
            bootloader_common_reset_rtc_retain_mem();
        }
        if (++rtc_retain_mem->reboot_counter == 0) {
            // do not allow to overflow. Stop it.
            --rtc_retain_mem->reboot_counter;
        }

    }

    if (partition != NULL) {
        rtc_retain_mem->partition.offset = partition->offset;
        rtc_retain_mem->partition.size   = partition->size;
    }

    update_rtc_retain_mem_crc();
}

rtc_retain_mem_t* bootloader_common_get_rtc_retain_mem(void)
{
    return rtc_retain_mem;
}
#endif // defined( CONFIG_BOOTLOADER_SKIP_VALIDATE_IN_DEEP_SLEEP ) || defined( CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC )