#pragma once

#include <cstdint>
#include <deque>
#include <map>
#include <set>
#include <string>
#include <vector>

#include "irc_config.h"
#include "irc_message.h"

namespace roro {

struct IrcLine {
    enum class Kind { Message, Action, Notice, Info, Own, OwnAction };
    int64_t utc;  // -1 if the clock wasn't set
    Kind kind;
    std::string nick;
    std::string text;
};

// One IRC conversation (see Buffer in CONTEXT.md).
struct IrcBuffer {
    enum class Type { Server, Channel, Query };
    std::string name;
    Type type;
    std::deque<IrcLine> lines;  // the most recent kLinesPerBuffer; full history goes to Logs
    int unread = 0;
    bool mentioned = false;
    bool joined = false;
    std::string topic;
};

struct IrcLogEntry {
    std::string buffer;
    IrcLine line;
};

// What the session wants done: lines to send, Log entries, Notification texts.
struct IrcEffects {
    std::vector<std::string> send;
    std::vector<IrcLogEntry> logs;
    std::vector<std::string> notifications;
};

// The IRC protocol, without any networking: registration (SASL PLAIN or NickServ), Buffers,
// unread counts, Mentions, the user's commands, and rejoining after a pause. The IRC Service
// feeds it received lines and carries out the effects.
class IrcSession {
   public:
    static constexpr size_t kLinesPerBuffer = 50;
    static constexpr int kMaxBuffers = 12;

    explicit IrcSession(const IrcConfig& config);

    // Joins wait this long for NickServ to confirm a login before going ahead anyway.
    static constexpr uint32_t kNickservWaitMs = 2000;

    // Uptime in ms, called regularly: releases joins held back for NickServ.
    void tick(uint32_t nowMs);

    void connected(int64_t utc);
    void disconnected(int64_t utc, const std::string& reason);
    void receive(const std::string& raw, int64_t utc);
    void input(int buffer, const std::string& text, int64_t utc);

    // The Buffer the user is looking at (-1: none); it neither counts unread nor notifies.
    void setViewing(int buffer);

    bool registered() const { return registered_; }
    bool quitRequested() const { return quit_; }
    const std::string& nick() const { return nick_; }

    int bufferCount() const { return static_cast<int>(buffers_.size()); }
    const IrcBuffer& buffer(int i) const { return buffers_[i]; }
    int totalUnread() const;
    // Changes whenever a Buffer gains a line or changes, so a view knows when to redraw.
    uint32_t revision() const { return revision_; }

    IrcEffects takeEffects();

   private:
    void send(const std::string& line) { effects_.send.push_back(line); }
    int findBuffer(const std::string& name) const;
    int bufferFor(const std::string& name, IrcBuffer::Type type);  // creates if needed and possible
    void add(int buffer, IrcLine::Kind kind, const std::string& nick, const std::string& text, int64_t utc,
             bool countsAsMention = false);
    void info(int buffer, const std::string& text, int64_t utc) { add(buffer, IrcLine::Kind::Info, "", text, utc); }
    bool mentionsMe(const std::string& text) const;
    void onPrivmsg(const IrcMessage& m, int64_t utc, bool notice);
    void onWelcome(const IrcMessage& m, int64_t utc);
    void joinChannels();
    void command(int buffer, const std::string& text, int64_t utc);
    void say(int buffer, const std::string& text, int64_t utc, bool action);

    const IrcConfig& config_;
    std::vector<IrcBuffer> buffers_;
    std::string nick_;
    bool registered_ = false;
    bool quit_ = false;
    int viewing_ = -1;
    std::set<std::string> namesRequested_;
    std::vector<std::string> rejoin_;  // IRC channels to join again after a reconnect
    std::map<std::string, std::string> keys_;  // lower-case IRC channel -> key, from config and /join
    bool joinsHeld_ = false;            // waiting for NickServ before joining
    bool saslFailed_ = false;
    uint32_t heldSinceMs_ = 0;
    uint32_t nowMs_ = 0;
    IrcEffects effects_;
    uint32_t revision_ = 0;
};

}  // namespace roro