#include "log.hpp"
#include <stdarg.h>
#include <string.h>
#include "util.hpp"
#ifdef __ANDROID__
#include <android/log.h>
#endif
#include <filesystem>
using namespace std::filesystem;
namespace Looper::Log {
    const std::locale LogStream::c_locale = std::locale("C");
    std::set<FILE*> LogStream::global_outputs;
    int LogStream::log_level =
    #ifdef DEBUG_MODE
    -2;
    #else
     0;
    #endif
    std::set<FILE*> LogStream::get_used_outputs() {
        std::set<FILE*> used_outputs;
        
        if (my_log_level >= log_level) {
	        for (auto my_output : outputs) {
	            used_outputs.insert(my_output);
	        }
        }
        for (auto global_output : global_outputs) {
            used_outputs.insert(global_output);
        }
        return used_outputs;
    }
    std::recursive_mutex log_mutex;
    void LogStream::_writec(const char chr) {
        if (nested) {
            for (auto &stream : streams) {
                stream->writec(chr);
            }
        } else {
#ifdef __ANDROID__
            bool is_newline = chr == '\n' || chr == '\r';
            if (!is_newline) {
                line += chr;
            } else {
                for (auto logPriority : android_outputs) {
                    __android_log_print(logPriority, "Looper", "%s", line.c_str());
                }
            }
#endif
            std::set<FILE*> used_outputs = get_used_outputs();
            for (auto &file : used_outputs) {
                fwrite(&chr, 1, 1, file);
                fflush(file);
            }
        }
    }
    void LogStream::writec(const char chr) {
        log_mutex_guard guard(log_mutex);
        bool is_newline = (chr == '\n' || chr == '\r');
        writeprefix();
        _writec(chr);
        if (is_newline) {
            need_prefix = true;
        }
    }
    void LogStream::writeprefix() {
        log_mutex_guard guard(log_mutex);
        if (need_prefix) {
            need_prefix = false;
            for (auto name : names) {
                writec('[');
                writes(name);
                writes("] ");
            }
        }
    }
    void LogStream::writes(const char *msg) {
        log_mutex_guard guard(log_mutex);
        while (*msg != '\0') {
            writec(*(msg++));
        }
    }
    void LogStream::writesn(const char *msg, size_t n) {
        log_mutex_guard guard(log_mutex);
        for (size_t i = 0; i < n && msg[i] != '\0'; i++) {
            writec(msg[i]);
        }
    }
    void LogStream::writes(std::string msg) {
        LogStream::writesn(msg.c_str(), msg.size());
    }
    void LogStream::writeln(const char *msg) {
        log_mutex_guard guard(log_mutex);
        LogStream::writes(msg);
        LogStream::writec('\n');
    }
    void LogStream::writeln_n(const char *msg, size_t n) {
        log_mutex_guard guard(log_mutex);
        LogStream::writesn(msg, n);
        LogStream::writec('\n');
    }
    void LogStream::writeln(std::string msg) {
        log_mutex_guard guard(log_mutex);
        LogStream::writes(msg);
        LogStream::writec('\n');
    }
    void LogStream::writef(const char *fmt, ...) {
        log_mutex_guard guard(log_mutex);
        va_list args;
        va_start(args, fmt);
        vwritef(fmt, args);
        va_end(args);
    }
    void LogStream::vwritef(const char *fmt, va_list args) {
        log_mutex_guard guard(log_mutex);
        const char *buf = vcformat(fmt, args);
        va_end(args);
        if (buf == NULL) {
            throw std::exception();
        }
        LogStream::writes(buf);
        free((void*)buf);
    }
    void LogStream::vwritefln(const char *fmt, va_list args) {
        log_mutex_guard guard(log_mutex);
        vwritef(fmt, args);
        writec('\n');
    }
    void LogStream::writefln(const char *fmt, ...) {
        log_mutex_guard guard(log_mutex);
        va_list args;
        va_start(args, fmt);
        vwritefln(fmt, args);
        va_end(args);
    }
    void LogStream::write_level_prefix(size_t level) {
        log_mutex_guard guard(log_mutex);
        for (size_t i = 0; i < level; i++) {
            writes("  ");
        }
    }
    void LogStream::write_level(size_t level, const char *msg) {
        log_mutex_guard guard(log_mutex);
        write_level_prefix(level);
        writeln(msg);
    }
    void LogStream::write_level(size_t level, std::string msg) {
        log_mutex_guard guard(log_mutex);
        write_level_prefix(level);
        writeln(msg);
    }
    void LogStream::vwritef_level(size_t level, const char *fmt, va_list args) {
        log_mutex_guard guard(log_mutex);
        write_level_prefix(level);
        vwritefln(fmt, args);
    }
    void LogStream::writef_level(size_t level, const char *fmt, ...) {
        log_mutex_guard guard(log_mutex);
        va_list args;
        va_start(args, fmt);
        vwritef_level(level, fmt, args);
        va_end(args);
    }
    LogStream::LogStream(std::initializer_list<std::string> names, int log_level, bool nested, void *discriminator)
    : names(names),
    need_prefix(true),
    my_log_level(log_level),
    nested(nested)
    {

    }
    LogStream &LogStream::substream(std::string name) {
        if (!this->substreams.contains(name)) {
            this->substreams[name] = new LogStream({name}, {this}, my_log_level);
        }
        return *this->substreams[name];

    }
    LogStream::LogStream(std::initializer_list<std::string> names, std::initializer_list<LogStream*> streams, int log_level)
    : LogStream(names, log_level, true, nullptr)
    {
        this->streams = std::set(streams);
    }
#ifdef __ANDROID__
    LogStream::LogStream(std::initializer_list<std::string> names, std::initializer_list<std::variant<FILE*, android_LogPriority>> outputs, int log_level)
#else
    LogStream::LogStream(std::initializer_list<std::string> names, std::initializer_list<FILE*> outputs, int log_level)
#endif
    : LogStream(names, log_level, false, nullptr)
    {
#ifdef __ANDROID__
        std::set<FILE*> file_outputs;
        std::set<android_LogPriority> android_outputs;
        for (auto output : outputs) {
            android_LogPriority *logPriority = std::get_if<android_LogPriority>(&output);
            FILE **file = std::get_if<FILE*>(&output);
            if (logPriority != nullptr) {
                android_outputs.insert(*logPriority);
            } else if (file != nullptr){
                file_outputs.insert(*file);
            }
        }
        this->android_outputs = android_outputs;
        this->outputs = file_outputs;
#else

        this->outputs = std::set(outputs);
#endif
    }
    LogStreamMap log_streams;
    void make_log_stream(int stream_id, log_stream_creation_function_t fn) {
        if (!log_streams.contains(stream_id)) {
            log_streams[stream_id] = std::stack<LogStream*>();
        }
        LogStream *new_stream = fn(stream_id);
        log_streams[stream_id].push(new_stream);
    }

    std::recursive_mutex log_stream_mutex;
    void init_logging_custom(log_stream_creation_function_t fn) {
        std::lock_guard<std::recursive_mutex> guard(log_stream_mutex);
        make_log_stream(-1, fn);
        make_log_stream(0, fn);
        make_log_stream(1, fn);
        make_log_stream(2, fn);
    }
    void pop_log_stream(int i) {
        log_streams[i].pop();
    }
    void pop_log_streams() {
        std::lock_guard<std::recursive_mutex> guard(log_stream_mutex);
        pop_log_stream(-1);
        pop_log_stream(0);
        pop_log_stream(1);
        pop_log_stream(2);
    }
    LogStream *_init_logging_normal(int id) {
        std::string name = get_log_name_by_idx(id);
#ifdef __ANDROID__
        std::map<int, android_LogPriority> stream_files = {
            {-2, ANDROID_LOG_DEBUG},
            {-1, ANDROID_LOG_DEBUG},
            {0, ANDROID_LOG_INFO},
            {1, ANDROID_LOG_WARN},
            {2, ANDROID_LOG_ERROR}
        };
#else
    std::map<int, FILE*> stream_files = {
            {-2, stderr},
            {-1, stderr},
            {0, stdout},
            {1, stderr},
            {2, stderr}
        };
#endif
        return new LogStream({name}, {stream_files[id]}, id);
    }
    std::string get_log_name_by_idx(int idx) {
        static std::map<int, std::string> stream_names = {
            {-2, "TRACE"},
            {-1, "DEBUG"},
            {0, "INFO"},
            {1, "WARNING"},
            {2, "ERROR"},
            {3, "FATAL"}
        };
        return stream_names[idx];
    }
    static FILE *log_file;
    void deinit_logging() {
    	fclose(log_file);
    }
    void init_logging() {
    	path prefs_path(get_prefs_path());
    	path log_dir = prefs_path / path("looper") / path("logs");
    	create_directories(log_dir);
    	log_file = fopen((log_dir / path("looper.log")).c_str(), "a");
    	LogStream::global_outputs.insert(log_file);
        init_logging_custom(_init_logging_normal);
        atexit(deinit_logging);
    }
    LogStream &get_log_stream_by_level(int level) {
        return *log_streams[level].top();
    }

}
extern "C" void write_log(int level, const char *log) {
    LOG(level).writes(log);
}
extern "C" void write_logln(int level, const char *log) {
    LOG(level).writeln(log);
}