#define BASIC_IMPL
#include "../pdf_browser/basic.h"
#include "filesystem.h"
#include "tests.h"
#include "raylib.h"

#include <thread>
#include <semaphore>
#include <mutex>

Arena Perm;

/*

TODO:
- New threading model idea: I could just spin up a bunch of threads and then don't kill them. Just use them for searching! Each one would have it's own xarena and so on.
- Improve scrolling
- Highlight selected line
- Improve the looks of the application
*/

struct TimeString {
    uint16_t hour;
    uint16_t minute;
    uint16_t second;
    String   string;
};

Array<TimeString> ParseSrtFile(Arena *arena, String filename) {
    String        content = ReadFile(*arena, filename);
    Array<String> lines   = Split(*arena, content, "\n");

    IterRemove(lines) {
        IterRemovePrepare(lines);
        it = Trim(it);
        if (it.len == 0) remove_item = true;
    }

    long              section_number = 1;
    Array<TimeString> time_strings   = {*arena};
    for (int i = 0; i < lines.len;) {
        String it0 = lines[i++];
        long   num = strtol(it0.data, NULL, 10);
        Assert(section_number == num);
        section_number += 1;

        TimeString item = {};
        String     it1  = lines[i++];
        item.hour       = (uint16_t)strtol(it1.data, NULL, 10);
        item.minute     = (uint16_t)strtol(it1.data + 3, NULL, 10);
        item.second     = (uint16_t)strtol(it1.data + 6, NULL, 10);

        String next_section_number = Format(*arena, "%d", section_number);
        while (i < lines.len && lines[i] != next_section_number) {
            String it   = lines[i];
            item.string = lines[i];
            time_strings.add(item);
            i += 1;
        }
    }

    IterRemove(time_strings) {
        IterRemovePrepare(time_strings);
        if (i > 0 && AreEqual(time_strings[i - 1].string, time_strings[i].string, true)) {
            remove_item = true;
        }
    }

    return time_strings;
}

struct TimeFile {
    Array<TimeString> time_strings;
    String            file;
};

struct ParseThreadIO {
    Array<String> input_files;

    // output
    Arena          *arena;
    Array<TimeFile> time_files;
};

void ParseThreadEntry(ParseThreadIO *io) {
    io->arena                = AllocArena();
    io->time_files.allocator = *io->arena;
    For(io->input_files) {
        Array<TimeString> time_strings = ParseSrtFile(io->arena, it);
        io->time_files.add({time_strings, it});
    }
}

struct XToTimeString {
    String   string; // String inside transcript arena
    uint16_t hour;
    uint16_t minute;
    uint16_t second;
    String   filepath;
};
Arena XArena;

void AddFolder(String folder, Array<String> *filenames, Array<XToTimeString> *x_to_time_string) {
    Scratch scratch;

    Array<String> srt_files = {scratch};
    for (FileIter iter = IterateFiles(scratch, folder); IsValid(iter); Advance(&iter)) {
        String file = Copy(Perm, iter.absolute_path);
        filenames->add(file);
        if (EndsWith(iter.filename, ".srt")) {
            srt_files.add(file);
        }
    }

    int64_t              thread_count     = 16;
    Array<std::thread *> threads          = {scratch};
    int64_t              files_per_thread = srt_files.len / thread_count;
    int64_t              remainder        = srt_files.len % thread_count;
    int64_t              fi               = 0;

    Array<ParseThreadIO> io = {scratch};
    io.reserve(thread_count);
    for (int ti = 0; ti < thread_count; ti += 1) {
        Array<String> files = {scratch};
        for (int i = 0; fi < srt_files.len && i < files_per_thread + remainder; fi += 1, i += 1) {
            files.add(srt_files[fi]);
        }
        if (remainder) remainder = 0;

        ParseThreadIO *i = io.alloc();
        i->input_files   = files;
        threads.add(new std::thread(ParseThreadEntry, i));
    }

    For(threads) {
        it->join();
        delete it;
    }

    ForItem(it_io, io) {
        ForItem(it_time_file, it_io.time_files) {
            For(it_time_file.time_strings) {
                String s      = Copy(XArena, it.string);
                s.data[s.len] = ' ';
                x_to_time_string->add({s, it.hour, it.minute, it.second, it_time_file.file});
            }
        }
        Release(it_io.arena);
    }
}

//
// Searching thread
//

Arena          MatchesArena;
Array<String>  Matches = {MatchesArena};
XToTimeString *ItemFound;
Array<char>    Prompt; // system allocated

std::mutex            SearchThreadArrayMutex;
std::binary_semaphore SearchThreadSemaphore{0};
bool                  SearchThreadStopSearching = false;
bool                  SearchThreadRunning       = true;
void                  SearchThreadEntry() {
    InitArena(&MatchesArena);
    for (;;) {
        SearchThreadSemaphore.acquire();
        if (!SearchThreadRunning) break;
        SearchThreadStopSearching = false;

        if (Prompt.len) {
            SearchThreadArrayMutex.lock();
            {
                Matches.clear();
            }
            SearchThreadArrayMutex.unlock();

            String  buffer = {(char *)XArena.data, (int64_t)XArena.len};
            String  find   = {Prompt.data, Prompt.len};
            int64_t index  = 0;
            while (Seek(buffer, find, &index, SeekFlag_IgnoreCase)) {
                String found = {buffer.data + index, find.len};
                SearchThreadArrayMutex.lock();
                {
                    Matches.add(found);
                }
                SearchThreadArrayMutex.unlock();

                if (SearchThreadStopSearching) break;
                buffer = buffer.skip(index + find.len);
            }
        }
    }
}

void SearchThreadClose(std::thread &thread) {
    SearchThreadRunning = false;
    SearchThreadSemaphore.release();
    thread.join();
}

int main() {
    InitOS();
    InitScratch();
    InitArena(&Perm);
    InitArena(&XArena);
    Arena *frame_arena = AllocArena();
    XArena.align       = 0;

    String start_string = "read=D:/zizek";
    For(start_string) Prompt.add(it);

    std::thread          search_thread(SearchThreadEntry);
    int64_t              chosen_text         = 0;
    int64_t              match_search_offset = 0;
    Array<String>        filenames           = {};
    Array<XToTimeString> x_to_time_string    = {};

    InitWindow(1920, 1080, "Transcript Browser");
    SetWindowState(FLAG_WINDOW_RESIZABLE);
    SetTargetFPS(60);
    Font font = LoadFontEx("C:/Windows/Fonts/consola.ttf", 20, 0, 250);
    while (!WindowShouldClose()) {
        Clear(frame_arena);

        for (int key = GetCharPressed(); key; key = GetCharPressed()) {
            UTF8Result utf8 = UTF32ToUTF8(key);
            if (utf8.error) {
                Prompt.add('?');
                continue;
            }

            for (int i = 0; i < utf8.len; i += 1) {
                Prompt.add(utf8.out_str[i]);
                match_search_offset       = 0;
                SearchThreadStopSearching = true;
                SearchThreadSemaphore.release();
            }
        }

        if (IsKeyPressed(KEY_BACKSPACE) || IsKeyPressedRepeat(KEY_BACKSPACE)) {
            if (ItemFound) {
                ItemFound = NULL;
            } else if (Prompt.len > 0) {
                Prompt.pop();
                match_search_offset       = 0;
                SearchThreadStopSearching = true;
                SearchThreadSemaphore.release();
            }
        }

        int64_t offset_size = 1;
        if (IsKeyDown(KEY_LEFT_CONTROL)) {
            offset_size = 10;
        }
        if (IsKeyPressed(KEY_DOWN) || IsKeyPressedRepeat(KEY_DOWN)) {
            chosen_text += offset_size;
            if (chosen_text > 10) match_search_offset += offset_size;
        }
        if (IsKeyPressed(KEY_UP) || IsKeyPressedRepeat(KEY_UP)) {
            chosen_text -= offset_size;
            match_search_offset -= offset_size;
        }
        chosen_text         = Clamp(chosen_text, (int64_t)0, Max(Matches.len - 1, (int64_t)0));
        match_search_offset = Clamp(match_search_offset, (int64_t)0, Max(Matches.len - 1 - 10, (int64_t)0));

        if (IsKeyPressed(KEY_ENTER)) {
            String prompt = {Prompt.data, Prompt.len};
            if (StartsWith(prompt, "read=")) {
                Prompt.add('\0');
                AddFolder(prompt.skip(5), &filenames, &x_to_time_string);
                Prompt.clear();
            } else if (ItemFound) {
                String base = ChopLastPeriod(ItemFound->filepath); // .srt
                base        = ChopLastPeriod(base);                // .en

                For(filenames) {
                    if (StartsWith(it, base)) {
                        if (EndsWith(it, ".mkv") || EndsWith(it, ".webm") || EndsWith(it, ".mp4")) {
                            int    seconds = ItemFound->hour * 60 * 60 + ItemFound->minute * 60 + ItemFound->second;
                            String copy    = Copy(*frame_arena, it);
                            for (int i = 0; i < copy.len; i += 1)
                                if (copy.data[i] == '/') copy.data[i] = '\\';
                            String args = Format(*frame_arena, "C:\\Program Files\\VideoLAN\\VLC\\vlc.exe --start-time %d \"%.*s\"", seconds, FmtString(copy));
                            printf("%.*s\n", FmtString(args));
                            RunEx(args);
                        }
                    }
                }
            } else if (Matches.len) {
                String string = Matches[chosen_text];
                For(x_to_time_string) {
                    uintptr_t begin  = (uintptr_t)(it.string.data);
                    uintptr_t end    = (uintptr_t)(it.string.data + it.string.len);
                    uintptr_t needle = (uintptr_t)string.data;

                    if (needle >= begin && needle < end) {
                        ItemFound = &it;
                        break;
                    }
                }
            }
        }
        BeginDrawing();
        ClearBackground(RAYWHITE);

        float font_size = 20;
        float y         = 0;
        int   xwidth    = (int)MeasureTextEx(font, "_", font_size, 1).x;

        if (ItemFound) {
            uintptr_t begin_region = (uintptr_t)XArena.data;
            uintptr_t end_region   = (uintptr_t)XArena.data + XArena.len;

            uintptr_t begin = (uintptr_t)(ItemFound->string.data - 1000);
            uintptr_t end   = (uintptr_t)(ItemFound->string.data + 1000);

            begin         = Clamp(begin, begin_region, end_region);
            end           = Clamp(end, begin_region, end_region);
            String string = {(char *)begin, (int64_t)(end - begin)};

            String filename = SkipToLastSlash(ItemFound->filepath);
            DrawTextEx(font, filename.data, {0, y}, font_size, 1, BLACK);
            y += font_size;

            int per_line = (GetRenderWidth() / xwidth) - 20;

            for (String it = string; it.len;) {
                String line = it.get_prefix(per_line);

                if (ItemFound->string.data >= line.data && ItemFound->string.data < line.data + line.len) {
                    DrawRectangleLines(0, (int)(y + font_size), GetRenderWidth(), 2, SKYBLUE);
                }

                String line_terminated = Copy(*frame_arena, line);
                DrawTextEx(font, line_terminated.data, {0, y}, font_size, 1, DARKGRAY);

                y += font_size;
                it = it.skip(per_line);
            }
        } else {
            Prompt.add('\0');
            DrawTextEx(font, "> ", {0, y}, font_size, 1, BLACK);
            DrawTextEx(font, Prompt.data, {(float)xwidth * 3, y}, font_size, 1, BLACK);
            Prompt.pop();
            y += font_size;

            int64_t chars_per_line = GetRenderWidth() / xwidth - Prompt.len;

            SearchThreadArrayMutex.lock();
            for (int64_t i = match_search_offset; i < Matches.len; i += 1) {
                String    it           = Matches[i];
                uintptr_t begin_region = (uintptr_t)XArena.data;
                uintptr_t end_region   = (uintptr_t)XArena.data + XArena.len;

                uintptr_t begin = (uintptr_t)(it.data - chars_per_line / 2);
                uintptr_t end   = (uintptr_t)(it.data + chars_per_line / 2);

                begin         = Clamp(begin, begin_region, end_region);
                end           = Clamp(end, begin_region, end_region);
                String string = Copy(*frame_arena, {(char *)begin, (int64_t)(end - begin)});

                String string_first  = Copy(*frame_arena, {(char *)begin, (int64_t)(it.data - begin)});
                String string_middle = Copy(*frame_arena, it);
                int    width         = (int)MeasureTextEx(font, string_first.data, font_size, 1).x;
                if (chosen_text == i) DrawRectangleLines(0, (int)(y + font_size), GetRenderWidth(), 2, SKYBLUE);

                String num = Format(*frame_arena, "%d", i);
                DrawTextEx(font, num.data, {0, y}, font_size, 1, DARKGRAY);
                DrawTextEx(font, string.data, {(float)xwidth * 4, y}, font_size, 1, DARKGRAY);
                DrawTextEx(font, string_middle.data, {(float)xwidth * 4 + (float)width, y}, font_size, 1, SKYBLUE);

                y += font_size;
                if (y > GetRenderHeight()) break;
            }
            SearchThreadArrayMutex.unlock();
        }

        if (IsKeyDown(KEY_F1)) DrawFPS(0, 0);
        EndDrawing();
    }
    CloseWindow();
    SearchThreadClose(search_thread);
}