#pragma once

#include <deque>
#include <sstream>
#include <stdint.h>
extern "C" {
#include <cosim_pcie_proto.h>
}
#include <nicbm.h>

//#define DEBUG_DEV
//#define DEBUG_ADMINQ
//#define DEBUG_LAN
//#define DEBUG_HMC
//#define DEBUG_QUEUES

struct i40e_aq_desc;
struct i40e_tx_desc;

namespace i40e {

class i40e_bm;
class lan;

class dma_base : public nicbm::DMAOp {
    public:
        /** i40e_bm will call this when dma is done */
        virtual void done() = 0;
};

class int_ev : public nicbm::TimedEvent {
    public:
        uint16_t vector;
        bool armed;

        int_ev();
};


class logger : public std::ostream {
    public:
        static const char endl = '\n';

    protected:
        std::string label;
        std::stringstream ss;

    public:
        logger(const std::string &label_);
        logger &operator<<(char c);
        logger &operator<<(int32_t c);
        logger &operator<<(uint8_t i);
        logger &operator<<(uint16_t i);
        logger &operator<<(uint32_t i);
        logger &operator<<(uint64_t i);
        logger &operator<<(bool c);
        logger &operator<<(const char *str);
        logger &operator<<(void *str);
};

/**
 * Base-class for descriptor queues (RX/TX, Admin RX/TX).
 *
 * Descriptor processing is split up into multiple phases:
 *
 *      - fetch: descriptor is read from host memory. This can be done in
 *        batches, while the batch sizes is limited by the minimum of
 *        MAX_ACTIVE_DESCS, max_active_capacity(), and max_fetch_capacity().
 *        Fetch is implemented by this base class.
 *
 *      - prepare: to be implemented in the sub class, but typically involves
 *        fetching buffer contents. Not guaranteed to happen in order. If
 *        overriden subclass must call desc_prepared() when done.
 *
 *      - process: to be implemented in the sub class. Guaranteed to be called
 *        in order. In case of tx, this actually sends the packet, in rx
 *        processing finishes when a packet for a descriptor has been received.
 *        subclass must call desc_processed() when done.
 *
 *      - write back: descriptor is written back to host-memory. Write-back
 *        capacity
 */
class queue_base {
    protected:
        static const uint32_t MAX_ACTIVE_DESCS = 128;

        class desc_ctx {
            friend class queue_base;
            public:
                enum state {
                    DESC_EMPTY,
                    DESC_FETCHING,
                    DESC_PREPARING,
                    DESC_PREPARED,
                    DESC_PROCESSING,
                    DESC_PROCESSED,
                    DESC_WRITING_BACK,
                    DESC_WRITTEN_BACK,
                };

            protected:
                queue_base &queue;
            public:
                enum state state;
                uint32_t index;
                void *desc;
                void *data;
                size_t data_len;
                size_t data_capacity;

                virtual void prepared();
                virtual void processed();

            protected:
                void data_fetch(uint64_t addr, size_t len);
                virtual void data_fetched(uint64_t addr, size_t len);
                void data_write(uint64_t addr, size_t len, const void *buf);
                virtual void data_written(uint64_t addr, size_t len);

            public:
                desc_ctx(queue_base &queue_);
                virtual ~desc_ctx();

                virtual void prepare();
                virtual void process() = 0;
        };

        class dma_fetch : public dma_base {
            protected:
                queue_base &queue;
            public:
                uint32_t pos;
                dma_fetch(queue_base &queue_, size_t len);
                virtual ~dma_fetch();
                virtual void done();
        };

        class dma_wb : public dma_base {
            protected:
                queue_base &queue;
            public:
                uint32_t pos;
                dma_wb(queue_base &queue_, size_t len);
                virtual ~dma_wb();
                virtual void done();
        };

        class dma_data_fetch : public dma_base {
            protected:
                desc_ctx &ctx;

            public:
                size_t total_len;
                size_t part_offset;
                dma_data_fetch(desc_ctx &ctx_, size_t len, void *buffer);
                virtual ~dma_data_fetch();
                virtual void done();
        };

        class dma_data_wb : public dma_base {
            protected:
                desc_ctx &ctx;
            public:
                size_t total_len;
                size_t part_offset;
                dma_data_wb(desc_ctx &ctx_, size_t len);
                virtual ~dma_data_wb();
                virtual void done();
        };

    public:
        std::string qname;
        logger log;
    protected:
        desc_ctx *desc_ctxs[MAX_ACTIVE_DESCS];
        uint32_t active_first_pos;
        uint32_t active_first_idx;
        uint32_t active_cnt;

        uint64_t base;
        uint32_t len;
        uint32_t &reg_head;
        uint32_t &reg_tail;

        bool enabled;
        size_t desc_len;

        void ctxs_init();

        void trigger_fetch();
        void trigger_process();
        void trigger_writeback();
        void trigger();

        // returns how many descriptors the queue can fetch max during the next
        // fetch: default UINT32_MAX, but can be overriden by child classes
        virtual uint32_t max_fetch_capacity();
        virtual uint32_t max_writeback_capacity();
        virtual uint32_t max_active_capacity();

        virtual desc_ctx &desc_ctx_create() = 0;

        // dummy function, needs to be overriden if interrupts are required
        virtual void interrupt();

        // this does the actual write-back. Can be overridden
        virtual void do_writeback(uint32_t first_idx, uint32_t first_pos,
                uint32_t cnt);

        // called by dma op when writeback has completed
        void writeback_done(uint32_t first_pos, uint32_t cnt);
    public:
        queue_base(const std::string &qname_, uint32_t &reg_head_,
                uint32_t &reg_tail_);
        virtual void reset();
        void reg_updated();
        bool is_enabled();
};

class queue_admin_tx : public queue_base {
    protected:
        class admin_desc_ctx : public desc_ctx {
            protected:
                queue_admin_tx &aq;
                i40e_bm &dev;
                struct i40e_aq_desc *d;

                virtual void data_written(uint64_t addr, size_t len);

                // prepare completion descriptor (fills flags, and return value)
                void desc_compl_prepare(uint16_t retval, uint16_t extra_flags);
                // complete direct response
                void desc_complete(uint16_t retval, uint16_t extra_flags = 0);
                // complete indirect response
                void desc_complete_indir(uint16_t retval, const void *data,
                        size_t len, uint16_t extra_flags = 0,
                        bool ignore_datalen=false);

            public:
                admin_desc_ctx(queue_admin_tx &queue_, i40e_bm &dev);

                virtual void prepare();
                virtual void process();
        };

        i40e_bm &dev;
        uint64_t &reg_base;
        uint32_t &reg_len;

        virtual desc_ctx &desc_ctx_create();
    public:
        queue_admin_tx(i40e_bm &dev_, uint64_t &reg_base_,
                uint32_t &reg_len_, uint32_t &reg_head_, uint32_t &reg_tail_);
        void reg_updated();
};

// host memory cache
class host_mem_cache {
    protected:
        static const uint16_t MAX_SEGMENTS = 0x1000;

        struct segment {
            uint64_t addr;
            uint16_t pgcount;
            bool valid;
            bool direct;
        };

        i40e_bm &dev;
        segment segs[MAX_SEGMENTS];

    public:
        class mem_op : public dma_base {
            public:
                bool failed;
        };

        host_mem_cache(i40e_bm &dev);
        void reset();
        void reg_updated(uint64_t addr);

        // issue a hmc memory operation (address is in the context
        void issue_mem_op(mem_op &op);
};

class lan_queue_base : public queue_base {
    protected:
        class qctx_fetch : public host_mem_cache::mem_op {
            public:
                lan_queue_base &lq;

                qctx_fetch(lan_queue_base &lq_);
                virtual void done();
        };


        lan &lanmgr;

        void ctx_fetched();
        void ctx_written_back();

        virtual void interrupt();
        virtual void initialize() = 0;

    public:
        bool enabling;
        size_t idx;
        uint32_t &reg_ena;
        uint32_t &fpm_basereg;
        uint32_t &reg_intqctl;
        size_t ctx_size;
        void *ctx;

        uint32_t reg_dummy_head;

        lan_queue_base(lan &lanmgr_, const std::string &qtype, uint32_t &reg_tail,
                size_t idx_,
                uint32_t &reg_ena_, uint32_t &fpm_basereg, uint32_t &reg_intqctl,
                uint16_t ctx_size);
        virtual void reset();
        void enable();
        void disable();
};

class lan_queue_tx : public lan_queue_base {
    protected:
        static const uint16_t MTU = 9024;

        class tx_desc_ctx : public desc_ctx {
            protected:
                lan_queue_tx &tq;

            public:
                i40e_tx_desc *d;

                tx_desc_ctx(lan_queue_tx &queue_);

                virtual void prepare();
                virtual void process();
                virtual void processed();
        };


        class dma_hwb : public dma_base {
            protected:
                lan_queue_tx &queue;
            public:
                uint32_t pos;
                uint32_t cnt;
                uint32_t next_head;
                dma_hwb(lan_queue_tx &queue_, uint32_t pos, uint32_t cnt,
                        uint32_t next_head);
                virtual ~dma_hwb();
                virtual void done();
        };

        uint8_t pktbuf[MTU];
        uint32_t tso_off;
        uint32_t tso_len;
        std::deque<tx_desc_ctx *> ready_segments;

        bool hwb;
        uint64_t hwb_addr;

        virtual void initialize();
        virtual desc_ctx &desc_ctx_create();

        virtual void do_writeback(uint32_t first_idx, uint32_t first_pos,
                uint32_t cnt);
        bool trigger_tx_packet();
        void trigger_tx();

    public:
        lan_queue_tx(lan &lanmgr_, uint32_t &reg_tail, size_t idx,
                uint32_t &reg_ena, uint32_t &fpm_basereg,
                uint32_t &reg_intqctl);
        virtual void reset();
};

class lan_queue_rx : public lan_queue_base {
    protected:
        class rx_desc_ctx : public desc_ctx {
            protected:
                lan_queue_rx &rq;
                virtual void data_written(uint64_t addr, size_t len);

            public:
                rx_desc_ctx(lan_queue_rx &queue_);
                virtual void process();
                void packet_received(const void *data, size_t len, bool last);
        };

        uint16_t dbuff_size;
        uint16_t hbuff_size;
        uint16_t rxmax;
        bool crc_strip;

        std::deque<rx_desc_ctx *> dcache;

        virtual void initialize();
        virtual desc_ctx &desc_ctx_create();

    public:
        lan_queue_rx(lan &lanmgr_, uint32_t &reg_tail, size_t idx,
                uint32_t &reg_ena, uint32_t &fpm_basereg,
                uint32_t &reg_intqctl);
        virtual void reset();
        void packet_received(const void *data, size_t len, uint32_t hash);
};

class rss_key_cache {
    protected:
        static const size_t key_len = 52;
        static const size_t cache_len = 288; // big enough for 2x ipv6 (2x128 + 2x16)
        bool cache_dirty;
        const uint32_t (&key)[key_len / 4];
        uint32_t cache[cache_len];

        void build();

    public:
        rss_key_cache(const uint32_t (&key_)[key_len / 4]);
        void set_dirty();
        uint32_t hash_ipv4(uint32_t sip, uint32_t dip, uint16_t sp,
                uint16_t dp);
};

// rx tx management
class lan {
    protected:
        friend class lan_queue_base;
        friend class lan_queue_tx;
        friend class lan_queue_rx;

        i40e_bm &dev;
        logger log;
        rss_key_cache rss_kc;
        const size_t num_qs;
        lan_queue_rx **rxqs;
        lan_queue_tx **txqs;

        bool rss_steering(const void *data, size_t len, uint16_t &queue,
                uint32_t &hash);
    public:
        lan(i40e_bm &dev, size_t num_qs);
        void reset();
        void qena_updated(uint16_t idx, bool rx);
        void tail_updated(uint16_t idx, bool rx);
        void rss_key_updated();
        void packet_received(const void *data, size_t len);
};

class shadow_ram {
    protected:
        i40e_bm &dev;
        logger log;

    public:
        shadow_ram(i40e_bm &dev);
        void reg_updated();
        uint16_t read(uint16_t addr);
        void write(uint16_t addr, uint16_t val);
};

class i40e_bm : public nicbm::Runner::Device {
protected:
    friend class queue_admin_tx;
    friend class host_mem_cache;
    friend class lan;
    friend class lan_queue_base;
    friend class lan_queue_rx;
    friend class lan_queue_tx;
    friend class shadow_ram;

    static const unsigned BAR_REGS = 0;
    static const unsigned BAR_IO = 2;

    static const uint32_t NUM_QUEUES = 1536;
    static const uint32_t NUM_PFINTS = 512;
    static const uint32_t NUM_VSIS = 384;
    static const uint16_t MAX_MTU = 2048;
    static const uint8_t NUM_ITR = 3;

    struct i40e_regs {
        uint32_t glgen_rstctl;
        uint32_t glgen_stat;
        uint32_t gllan_rctl_0;
        uint32_t pfint_lnklst0;
        uint32_t pfint_icr0_ena;
        uint32_t pfint_icr0;
        uint32_t pfint_itr0[NUM_ITR];

        uint32_t pfint_dyn_ctl0;
        uint32_t pfint_dyn_ctln[NUM_PFINTS - 1];
        uint32_t pfint_lnklstn[NUM_PFINTS - 1];
        uint32_t pfint_raten[NUM_PFINTS - 1];
        uint32_t gllan_txpre_qdis[12];

        uint32_t glnvm_srctl;
        uint32_t glnvm_srdata;

        uint32_t qint_tqctl[NUM_QUEUES];
        uint32_t qtx_ena[NUM_QUEUES];
        uint32_t qtx_tail[NUM_QUEUES];
        uint32_t qint_rqctl[NUM_QUEUES];
        uint32_t qrx_ena[NUM_QUEUES];
        uint32_t qrx_tail[NUM_QUEUES];

        uint32_t glhmc_lantxbase[16];
        uint32_t glhmc_lantxcnt[16];
        uint32_t glhmc_lanrxbase[16];
        uint32_t glhmc_lanrxcnt[16];

        uint32_t pfhmc_sdcmd;
        uint32_t pfhmc_sddatalow;
        uint32_t pfhmc_sddatahigh;
        uint32_t pfhmc_pdinv;
        uint32_t pfhmc_errorinfo;
        uint32_t pfhmc_errordata;

        uint64_t pf_atqba;
        uint32_t pf_atqlen;
        uint32_t pf_atqh;
        uint32_t pf_atqt;

        uint64_t pf_arqba;
        uint32_t pf_arqlen;
        uint32_t pf_arqh;
        uint32_t pf_arqt;

        uint32_t pfqf_ctl_0;

        uint32_t pfqf_hkey[13];
        uint32_t pfqf_hlut[128];
    };

public:
    i40e_bm();
    ~i40e_bm();

    virtual void setup_intro(struct cosim_pcie_proto_dev_intro &di);
    virtual void reg_read(uint8_t bar, uint64_t addr, void *dest, size_t len);
    virtual uint32_t reg_read32(uint8_t bar, uint64_t addr);
    virtual void reg_write(uint8_t bar, uint64_t addr, const void *src,
            size_t len);
    virtual void reg_write32(uint8_t bar, uint64_t addr, uint32_t val);
    virtual void dma_complete(nicbm::DMAOp &op);
    virtual void eth_rx(uint8_t port, const void *data, size_t len);
    virtual void timed_event(nicbm::TimedEvent &ev);

    void signal_interrupt(uint16_t vector, uint8_t itr);

protected:
    logger log;
    i40e_regs regs;
    queue_admin_tx pf_atq;
    host_mem_cache hmc;
    shadow_ram shram;
    lan lanmgr;

    int_ev intevs[NUM_PFINTS];

    /** Read from the I/O bar */
    virtual uint32_t reg_io_read(uint64_t addr);
    /** Write to the I/O bar */
    virtual void reg_io_write(uint64_t addr, uint32_t val);

    /** 32-bit read from the memory bar (should be the default) */
    virtual uint32_t reg_mem_read32(uint64_t addr);
    /** 32-bit write to the memory bar (should be the default) */
    virtual void reg_mem_write32(uint64_t addr, uint32_t val);

    void reset(bool indicate_done);
};

// places the tcp checksum in the packet (assuming ipv4)
void xsum_tcp(void *tcphdr, size_t l4len);

// calculates the full ipv4 & tcp checksum without assuming any pseudo header
// xsums
void xsum_tcpip_tso(void *iphdr, uint8_t iplen, uint8_t l4len,
        uint16_t paylen);

void tso_postupdate_header(void *iphdr, uint8_t iplen, uint8_t l4len,
        uint16_t paylen);

} // namespace corundum
