#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <string.h>
#include "engine.h"
#include "tui.h"
#include "cli.h"
#include "gui.h"
#include "dispatcher.h"
#include "carla.h"
#include "fs.h"

static Engine engine;
static volatile int keep_running = 1;
static DispatchFn dispatch = NULL;

void signal_handler(int sig) {
    (void)sig;
    keep_running = 0;
    if (dispatch) {
        Action action = { .type = ACTION_QUIT };
        dispatch(action);
    }
}

void print_usage(const char *program) {
    printf("Usage: %s [options]\n", program);
    printf("Options:\n");
    printf("  -n <name>    JACK client name (default: jack-looper)\n");
    printf("  -c <channel> MIDI control channel (default: 0)\n");
    printf("  -t           Use TUI frontend (default)\n");
    printf("  -i           Use CLI frontend (interactive)\n");
    printf("  -g           Use GUI frontend\n");
    printf("  -h           Show this help\n");
}

int main(int argc, char *argv[]) {
    const char *client_name = "jack-looper";
    int control_channel = 0;
    enum { FRONTEND_TUI, FRONTEND_CLI, FRONTEND_GUI } frontend = FRONTEND_TUI;
    int opt;
    
    while ((opt = getopt(argc, argv, "n:c:tigh")) != -1) {
        switch (opt) {
            case 'n':
                client_name = optarg;
                break;
            case 'c':
                control_channel = atoi(optarg);
                if (control_channel < 0 || control_channel > 15) {
                    fprintf(stderr, "Control channel must be 0-15\n");
                    return 1;
                }
                break;
            case 't':
                frontend = FRONTEND_TUI;
                break;
            case 'i':
                frontend = FRONTEND_CLI;
                break;
            case 'g':
                frontend = FRONTEND_GUI;
                break;
            case 'h':
                print_usage(argv[0]);
                return 0;
            default:
                print_usage(argv[0]);
                return 1;
        }
    }
    
    // Create initial state (heap-allocated to avoid stack overflow)
    AppState *initial_state = calloc(1, sizeof(AppState));
    if (!initial_state) {
        fprintf(stderr, "Failed to allocate initial state\n");
        return 1;
    }
    initial_state->transport_state = TRANSPORT_STOPPED;
    initial_state->clock_source = CLOCK_SOURCE_INTERNAL;
    initial_state->bpm = 120.0;
    initial_state->quantize_mode = QUANTIZE_OFF;
    initial_state->quantize_threshold = 0;
    initial_state->running = true;
    
    for (int i = 0; i < MAX_CLIPS; i++) {
        initial_state->clips[i].state = CLIP_EMPTY;
        initial_state->clips[i].buffer = (float *)calloc(MAX_BUFFER_SIZE, sizeof(float));
        if (!initial_state->clips[i].buffer) {
            fprintf(stderr, "Failed to allocate buffer for clip %d\n", i);
            // Cleanup previously allocated buffers
            for (int j = 0; j < i; j++) {
                free(initial_state->clips[j].buffer);
            }
            free(initial_state);
            return 1;
        }
        initial_state->clips[i].buffer_size = 0;
        initial_state->clips[i].write_position = 0;
        initial_state->clips[i].read_position = 0;
        
        // Initialize MIDI clips
        initial_state->midi_clips[i].state = CLIP_EMPTY;
        initial_state->midi_clips[i].event_count = 0;
        initial_state->midi_clips[i].read_index = 0;
        initial_state->midi_clips[i].events = (MidiEvent *)calloc(MAX_MIDI_EVENTS, sizeof(MidiEvent));
        if (!initial_state->midi_clips[i].events) {
            fprintf(stderr, "Failed to allocate MIDI events for clip %d\n", i);
            // Cleanup previously allocated buffers and events
            for (int j = 0; j < i; j++) {
                free(initial_state->clips[j].buffer);
                free(initial_state->midi_clips[j].events);
            }
            free(initial_state);
            return 1;
        }
        initial_state->midi_clips[i].max_events = MAX_MIDI_EVENTS;
    }
    
    // Initialize channel names
    for (int ch = 0; ch < MAX_CHANNELS; ch++) {
        snprintf(initial_state->channel_names[ch], 64, "Channel %d", ch);
    }
    initial_state->show_midi_grid = false;
    
    // Carla host is now initialized in engine_init
    // Initialize dispatcher
    dispatch = dispatcher_init(initial_state);
    free(initial_state);
    
    // Initialize filesystem module (auto-save thread)
    fs_init();
    
    // Initialize engine
    if (engine_init(&engine, client_name, dispatch) != 0) {
        fprintf(stderr, "Failed to initialize engine\n");
        return 1;
    }
    
    // Set up signal handler
    signal(SIGINT, signal_handler);
    signal(SIGTERM, signal_handler);
    
    // Start dispatcher
    dispatcher_start();
    
    // Start engine
    if (engine_start(&engine) != 0) {
        fprintf(stderr, "Failed to start engine\n");
        engine_cleanup(&engine);
        dispatcher_stop();
        return 1;
    }
    
    printf("JACK Looper started\n");
    printf("Client name: %s\n", client_name);
    printf("Control channel: %d\n", control_channel);
    printf("Sample rate: %u Hz\n", engine.sample_rate);
    printf("Press Ctrl+C to stop\n\n");
    
    // Load project file if specified
    if (optind < argc) {
        const char *wheel_file = argv[optind];
        size_t len = strlen(wheel_file);
        if (len > 6 && strcmp(wheel_file + len - 6, ".wheel") == 0) {
            Action action = { .type = ACTION_LOAD_PROJECT };
            strncpy(action.data.load_project.filename, wheel_file, sizeof(action.data.load_project.filename) - 1);
            action.data.load_project.filename[sizeof(action.data.load_project.filename) - 1] = '\0';
            dispatch(action);
        }
    }
    
    // Run selected frontend
    switch (frontend) {
        case FRONTEND_TUI:
            tui_init(&engine);
            tui_run(&engine);
            tui_cleanup();
            break;
        case FRONTEND_CLI:
            cli_run(&engine);
            break;
        case FRONTEND_GUI:
            gui_main(&engine);
            break;
    }
    
    // Cleanup
    printf("\nShutting down...\n");
    engine_stop(&engine);
    engine_cleanup(&engine);
    fs_cleanup();
    dispatcher_stop();
    
    return 0;
}