#include "Log.h"
#include "Settings.h"
#include "Terminal/Terminal.h"
#include "System.h"
#include "Map.h"
#include "LEDHook.h"

static uint8_t LogMem[LOG_SIZE];
static uint8_t *LogMemPtr;
static uint16_t LogMemLeft;
static uint16_t LogFRAMAddr = FRAM_LOG_START_ADDR;
static uint8_t EEMEM LogFRAMAddrValid = false;
static bool EnableLogSRAMtoFRAM = false;
LogFuncType CurrentLogFunc;

static const MapEntryType PROGMEM LogModeMap[] = {
    { .Id = LOG_MODE_OFF, 		.Text = "OFF" 		},
    { .Id = LOG_MODE_MEMORY, 	.Text = "MEMORY" 	},
    { .Id = LOG_MODE_LIVE, 	.Text = "LIVE" 	}
};

static void LogFuncOff(LogEntryEnum Entry, const void *Data, uint8_t Length) {
    /* Do nothing */
}

static void LogFuncMemory(LogEntryEnum Entry, const void *Data, uint8_t Length) {
    uint16_t SysTick = SystemGetSysTick();

    if (LogMemLeft >= (Length + 4)) {
        LogMemLeft -= Length + 4;

        uint8_t *DataPtr = (uint8_t *) Data;

        /* Write down Entry Id, Data length and Timestamp */
        *LogMemPtr++ = (uint8_t) Entry;
        *LogMemPtr++ = (uint8_t) Length;
        *LogMemPtr++ = (uint8_t)(SysTick >> 8);
        *LogMemPtr++ = (uint8_t)(SysTick >> 0);

        /* Write down data bytes */
        while (Length--) {
            *LogMemPtr++ = *DataPtr++;
        }
    } else {
        /* If memory full. Deactivate logmode */
        LogSetModeById(LOG_MODE_OFF);
        LEDHook(LED_LOG_MEM_FULL, LED_ON);
    }
}

static void LogFuncLive(LogEntryEnum Entry, const void *Data, uint8_t Length) {
    uint16_t SysTick = SystemGetSysTick();

    TerminalSendByte((uint8_t) Entry);
    TerminalSendByte((uint8_t) Length);
    TerminalSendByte((uint8_t)(SysTick >> 8));
    TerminalSendByte((uint8_t)(SysTick >> 0));
    TerminalSendBlock(Data, Length);
}

void LogInit(void) {
    LogSetModeById(GlobalSettings.ActiveSettingPtr->LogMode);
    LogMemPtr = LogMem;
    LogMemLeft = sizeof(LogMem);

    uint8_t result;
    ReadEEPBlock((uint16_t) &LogFRAMAddrValid, &result, 1);
    memset(LogMemPtr, LOG_EMPTY, LOG_SIZE);
    if (result) {
        MemoryReadBlock(&LogFRAMAddr, FRAM_LOG_ADDR_ADDR, 2);
    } else {
        LogFRAMAddr = FRAM_LOG_START_ADDR;
        MemoryWriteBlock(&LogFRAMAddr, FRAM_LOG_ADDR_ADDR, 2);
        result = true;
        WriteEEPBlock((uint16_t) &LogFRAMAddrValid, &result, 1);
    }

    LogEntry(LOG_INFO_SYSTEM_BOOT, NULL, 0);
}

void LogTick(void) {
    if (EnableLogSRAMtoFRAM)
        LogSRAMToFRAM();
}

void LogTask(void) {

}

bool LogMemLoadBlock(void *Buffer, uint32_t BlockAddress, uint16_t ByteCount) {
    if (BlockAddress < sizeof(LogMem) + (LogFRAMAddr - FRAM_LOG_START_ADDR)) {
        bool overflow = false;
        uint16_t remainderByteCount = 0;
        uint16_t SizeInFRAMStored = LogFRAMAddr - FRAM_LOG_START_ADDR;
        // prevent buffer overflows:
        if ((BlockAddress + ByteCount) >= sizeof(LogMem) + SizeInFRAMStored) {
            overflow = true;
            uint16_t tmp = sizeof(LogMem) + SizeInFRAMStored - BlockAddress;
            remainderByteCount = ByteCount - tmp;
            ByteCount = tmp;
        }

        /*
         * 1. case: The whole block is in FRAM.
         * 2. case: The block wraps from FRAM to SRAM
         * 3. case: The whole block is in SRAM.
         */
        if (BlockAddress < SizeInFRAMStored && (BlockAddress + ByteCount) < SizeInFRAMStored) {
            MemoryReadBlock(Buffer, BlockAddress + FRAM_LOG_START_ADDR, ByteCount);
        } else if (BlockAddress < SizeInFRAMStored) {
            uint16_t FramByteCount = SizeInFRAMStored - BlockAddress;
            MemoryReadBlock(Buffer, BlockAddress + FRAM_LOG_START_ADDR, FramByteCount);
            memcpy(Buffer + FramByteCount, LogMem, ByteCount - FramByteCount);
        } else {
            memcpy(Buffer, LogMem + BlockAddress - SizeInFRAMStored, ByteCount);
        }

        if (overflow) {
            while (remainderByteCount--)
                ((uint8_t *) Buffer)[ByteCount + remainderByteCount] = 0x00;
        }

        return true;
    } else {
        return false;
    }
}

INLINE void LogSRAMClear(void) {
    uint16_t i, until = LOG_SIZE - LogMemLeft;

    for (i = 0; i < until; i++) {
        LogMem[i] = (uint8_t) LOG_EMPTY;
    }

    LogMemPtr = LogMem;
    LogMemLeft = sizeof(LogMem);
}

void LogMemClear(void) {
    LogSRAMClear();
    LogFRAMAddr = FRAM_LOG_START_ADDR;
    MemoryWriteBlock(&LogFRAMAddr, FRAM_LOG_ADDR_ADDR, 2);
    LEDHook(LED_LOG_MEM_FULL, LED_OFF);
}

uint16_t LogMemFree(void) {
    return LogMemLeft + FRAM_LOG_SIZE - LogFRAMAddr + FRAM_LOG_START_ADDR;
}


void LogSetModeById(LogModeEnum Mode) {
#ifndef LOG_SETTING_GLOBAL
    GlobalSettings.ActiveSettingPtr->LogMode = Mode;
#else
    /* Write Log settings globally */
    for (uint8_t i = 0; i < SETTINGS_COUNT; i++) {
        GlobalSettings.Settings[i].LogMode = Mode;
    }
#endif

    switch (Mode) {
        case LOG_MODE_OFF:
            EnableLogSRAMtoFRAM = false;
            CurrentLogFunc = LogFuncOff;
            break;

        case LOG_MODE_MEMORY:
            EnableLogSRAMtoFRAM = true;
            CurrentLogFunc = LogFuncMemory;
            break;

        case LOG_MODE_LIVE:
            EnableLogSRAMtoFRAM = false;
            CurrentLogFunc = LogFuncLive;
            break;

        default:
            break;
    }

}

bool LogSetModeByName(const char *Mode) {
    MapIdType Id;

    if (MapTextToId(LogModeMap, ARRAY_COUNT(LogModeMap), Mode, &Id)) {
        LogSetModeById(Id);
        return true;
    }

    return false;
}

void LogGetModeByName(char *Mode, uint16_t BufferSize) {
    MapIdToText(LogModeMap, ARRAY_COUNT(LogModeMap),
                GlobalSettings.ActiveSettingPtr->LogMode, Mode, BufferSize);
}

void LogGetModeList(char *List, uint16_t BufferSize) {
    MapToString(LogModeMap, ARRAY_COUNT(LogModeMap), List, BufferSize);
}

void LogSRAMToFRAM(void) {
    if (LogMemLeft < LOG_SIZE) {
        uint16_t FRAM_Free = FRAM_LOG_SIZE - (LogFRAMAddr - FRAM_LOG_START_ADDR);

        if (FRAM_Free >= LOG_SIZE - LogMemLeft) {
            MemoryWriteBlock(LogMem, LogFRAMAddr, LOG_SIZE - LogMemLeft);
            LogFRAMAddr += LOG_SIZE - LogMemLeft;
            LogSRAMClear();
            MemoryWriteBlock(&LogFRAMAddr, FRAM_LOG_ADDR_ADDR, 2);
        } else if (FRAM_Free > 0) {
            // not everything fits in FRAM, simply write as much as possible to FRAM
            MemoryWriteBlock(LogMem, LogFRAMAddr, FRAM_Free);
            memmove(LogMem, LogMem + FRAM_Free, LOG_SIZE - FRAM_Free); // FRAM_Free is < LOG_SIZE - LogMemLeft and thus also < LOG_SIZE

            LogMemPtr -= FRAM_Free;
            LogMemLeft += FRAM_Free;
            LogFRAMAddr += FRAM_Free;
            MemoryWriteBlock(&LogFRAMAddr, FRAM_LOG_ADDR_ADDR, 2);
        } else {
            // TODO handle the case in which the FRAM is full
        }
    }
}