#include "ui_renderer.h"
#include "spacecraft.h"
#include "maneuver.h"
#include <cstdio>
#include <cstring>
#include <cmath>

// raygui implementation (header-only library)
#define RAYGUI_IMPLEMENTATION
#include "raygui.h"
#include "amber/style_amber.h"

void gui_init() {
    GuiLoadStyleAmber();
}

// Render simulation information overlay
void render_info(SimulationState* sim) {
    // Panel dimensions
    int panel_width = 300;
    int panel_height = 300;
    int panel_x = 10;
    int panel_y = GetScreenHeight() - panel_height - 10;

    Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };

    // Draw window
    if (GuiWindowBox(panel_bounds, "Info")) {
        // Window box close button doesn't close this panel
    }

    // Prepare info text
    char info_text[1024];
    char temp_buffer[512];

    snprintf(info_text, sizeof(info_text), "Orbital Mechanics Simulation\n\n");

    // Config name
    if (sim->config_name[0] != '\0') {
        snprintf(temp_buffer, sizeof(temp_buffer), "Config: %s\n\n", sim->config_name);
        strcat(info_text, temp_buffer);
    }

    // Simulation time (in days)
    double days = sim->time / 86400.0;  // seconds to days
    snprintf(temp_buffer, sizeof(temp_buffer), "Time: %.2f days\n", days);
    strcat(info_text, temp_buffer);

    // Body count
    snprintf(temp_buffer, sizeof(temp_buffer), "Bodies: %d\n", sim->body_count);
    strcat(info_text, temp_buffer);

    // FPS
    snprintf(temp_buffer, sizeof(temp_buffer), "FPS: %d\n\n", GetFPS());
    strcat(info_text, temp_buffer);

    // Controls
    strcat(info_text, "Controls:\n");
    strcat(info_text, "  Arrows: Rotate/Zoom\n");
    strcat(info_text, "  Space: Pause/Resume\n");
    strcat(info_text, "  +/-: Speed control\n");
    strcat(info_text, "  ESC: Quit\n");

    // Draw info text (inside window, leave space for title bar)
    Rectangle text_bounds = {
        (float)panel_x + 8,
        (float)panel_y + 25,
        (float)panel_width - 16,
        (float)panel_height - 29
    };

    GuiLabel(text_bounds, info_text);
}

// Render body list UI panel
void render_body_list_ui(SimulationState* sim, RenderState* render_state, UIState* ui_state) {
    // Panel dimensions
    int panel_width = 200;
    int panel_height = 400;
    int panel_x = 10;
    int panel_y = 10;

    Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };

    // Create list string for raygui (NULL-terminated)
    // Include both bodies and spacecraft
    int total_items = sim->body_count + sim->craft_count;
    int buffer_size = total_items * (64 + 3 + 1) + 1; // Extra space for "🚀 " prefix
    char* list_text = (char*)malloc(buffer_size);
    if (!list_text) return;

    list_text[0] = '\0';
    int offset = 0;
    int item_index = 0;

    // Add bodies to list
    for (int i = 0; i < sim->body_count; i++) {
        if (item_index > 0) {
            offset += snprintf(list_text + offset, buffer_size - offset, ";");
        }
        offset += snprintf(list_text + offset, buffer_size - offset, "%s", sim->bodies[i].name);
        item_index++;
    }

    // Add spacecraft to list with "🚀 " prefix
    for (int i = 0; i < sim->craft_count; i++) {
        offset += snprintf(list_text + offset, buffer_size - offset, ";");
        offset += snprintf(list_text + offset, buffer_size - offset, "🚀 %s", sim->spacecraft[i].name);
        item_index++;
    }

    // Draw window (no close button - panels always shown)
    GuiWindowBox(panel_bounds, "Objects");

    // Draw list view (inside window, leave space for title bar)
    Rectangle list_bounds = {
        (float)panel_x + 4,
        (float)panel_y + 25,
        (float)panel_width - 8,
        (float)panel_height - 29
    };

    int previous_active = ui_state->body_list_active;
    GuiListView(list_bounds, list_text, &ui_state->body_list_scroll, &ui_state->body_list_active);

    // Check if an item was selected
    if (ui_state->body_list_active >= 0 && ui_state->body_list_active != previous_active) {
        if (ui_state->body_list_active < sim->body_count) {
            // A body was selected
            render_state->selected_body_index = ui_state->body_list_active;
            render_state->selected_craft_index = -1;
            render_state->camera_follow_body = true;
            printf("Camera follow enabled for body: %s\n", sim->bodies[render_state->selected_body_index].name);
        } else {
            // A spacecraft was selected
            int craft_index = ui_state->body_list_active - sim->body_count;
            if (craft_index >= 0 && craft_index < sim->craft_count) {
                render_state->selected_body_index = -1;
                render_state->selected_craft_index = craft_index;
                render_state->camera_follow_body = true;
                printf("Camera follow enabled for spacecraft: %s\n", sim->spacecraft[craft_index].name);
            }
        }
    }

    free(list_text);
}

// Render body information UI panel
void render_body_info_ui(SimulationState* sim, RenderState* render_state) {
    // Panel dimensions
    int panel_width = 250;
    int panel_height = 300;
    int panel_x = GetScreenWidth() - panel_width - 10;
    int panel_y = 10;

    if ((render_state->selected_body_index < 0 || render_state->selected_body_index >= sim->body_count) &&
        (render_state->selected_craft_index < 0 || render_state->selected_craft_index >= sim->craft_count)) {
        // No body or spacecraft selected - render empty panel
        Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };
        GuiWindowBox(panel_bounds, "Info");
        return;
    }

    Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };

    // Check if a body is selected
    if (render_state->selected_body_index >= 0 && render_state->selected_body_index < sim->body_count) {
        CelestialBody* body = &sim->bodies[render_state->selected_body_index];

        // Draw window (no close button - panels always shown)
        GuiWindowBox(panel_bounds, body->name);

        // Prepare info text
        char info_text[1024];
        char temp_buffer[256];

        snprintf(info_text, sizeof(info_text), "Name: %s", body->name);

        snprintf(temp_buffer, sizeof(temp_buffer), "Mass: %.2e kg", body->mass);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        snprintf(temp_buffer, sizeof(temp_buffer), "Radius: %.2e m", body->radius);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        if (body->parent_index <= 0) {
            // Position
            snprintf(temp_buffer, sizeof(temp_buffer), "Position: (%.2e, %.2e, %.2e)",
                     body->global_position.x, body->global_position.y, body->global_position.z);
            strcat(info_text, "\n");
            strcat(info_text, temp_buffer);

            // Velocity
            double vel_mag = vec3_magnitude(body->global_velocity);
            snprintf(temp_buffer, sizeof(temp_buffer), "Velocity: %.2f m/s", vel_mag);
            strcat(info_text, "\n");
            strcat(info_text, temp_buffer);
        } else {
            // Position (Local)
            snprintf(temp_buffer, sizeof(temp_buffer), "local_position: (%.2e, %.2e, %.2e)",
                     body->local_position.x, body->local_position.y, body->local_position.z);
            strcat(info_text, "\n");
            strcat(info_text, temp_buffer);

            // Velocity (Local)
            double parent_vel_mag = vec3_magnitude(sim->bodies[body->parent_index].global_velocity);
            double vel_mag = vec3_magnitude(body->global_velocity) - parent_vel_mag;
            snprintf(temp_buffer, sizeof(temp_buffer), "local_velocity: %.2f m/s", vel_mag);
            strcat(info_text, "\n");
            strcat(info_text, temp_buffer);
        }

        // Orbital elements
        snprintf(temp_buffer, sizeof(temp_buffer), "Eccentricity: %.3f", body->orbit.eccentricity);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        snprintf(temp_buffer, sizeof(temp_buffer), "Semi-major axis: %.2e m", body->orbit.semi_major_axis);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        // Parent body
        if (body->parent_index >= 0 && body->parent_index < sim->body_count) {
            snprintf(temp_buffer, sizeof(temp_buffer), "Parent: %s", sim->bodies[body->parent_index].name);
        } else {
            snprintf(temp_buffer, sizeof(temp_buffer), "Parent: None");
        }
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        // SOI
        snprintf(temp_buffer, sizeof(temp_buffer), "SOI radius: %.2e m", body->soi_radius);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        // Draw info text (inside window, leave space for title bar)
        Rectangle text_bounds = {
            (float)panel_x + 8,
            (float)panel_y + 25,
            (float)panel_width - 16,
            (float)panel_height - 29
        };

        GuiLabel(text_bounds, info_text);
        return;
    }

    // Check if a spacecraft is selected
    if (render_state->selected_craft_index >= 0 && render_state->selected_craft_index < sim->craft_count) {
        Spacecraft* craft = &sim->spacecraft[render_state->selected_craft_index];

        // Draw window (no close button - panels always shown)
        GuiWindowBox(panel_bounds, craft->name);

        // Prepare info text
        char info_text[1024];
        char temp_buffer[256];

        snprintf(info_text, sizeof(info_text), "Name: %s", craft->name);

        snprintf(temp_buffer, sizeof(temp_buffer), "Mass: %.2e kg", craft->mass);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        // Position (Local)
        snprintf(temp_buffer, sizeof(temp_buffer), "local_position: (%.2e, %.2e, %.2e)",
                 craft->local_position.x, craft->local_position.y, craft->local_position.z);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        // Velocity (Local)
        double vel_mag = vec3_magnitude(craft->local_velocity);
        snprintf(temp_buffer, sizeof(temp_buffer), "local_velocity: %.2f m/s", vel_mag);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        // Parent body
        if (craft->parent_index >= 0 && craft->parent_index < sim->body_count) {
            snprintf(temp_buffer, sizeof(temp_buffer), "Parent: %s", sim->bodies[craft->parent_index].name);
        } else {
            snprintf(temp_buffer, sizeof(temp_buffer), "Parent: None");
        }
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        // Maneuver info
        int pending_maneuvers = 0;
        int executed_maneuvers = 0;
        for (int i = 0; i < sim->maneuver_count; i++) {
            if (sim->maneuvers[i].craft_index == render_state->selected_craft_index) {
                if (sim->maneuvers[i].executed) {
                    executed_maneuvers++;
                } else {
                    pending_maneuvers++;
                }
            }
        }

        snprintf(temp_buffer, sizeof(temp_buffer), "Pending maneuvers: %d", pending_maneuvers);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        snprintf(temp_buffer, sizeof(temp_buffer), "Executed maneuvers: %d", executed_maneuvers);
        strcat(info_text, "\n");
        strcat(info_text, temp_buffer);

        // Draw info text (inside window, leave space for title bar)
        Rectangle text_bounds = {
            (float)panel_x + 8,
            (float)panel_y + 25,
            (float)panel_width - 16,
            (float)panel_height - 29
        };

        GuiLabel(text_bounds, info_text);
        return;
    }
}

// Render maneuver list UI panel
void render_maneuver_list_ui(SimulationState* sim, RenderState* render_state) {
    if (render_state->selected_craft_index < 0 || render_state->selected_craft_index >= sim->craft_count) {
        return; // No spacecraft selected
    }

    int panel_width = 300;
    int panel_height = 400;
    int panel_x = GetScreenWidth() - panel_width - 10;
    int panel_y = 320; // Below info panel

    Rectangle panel_bounds = { (float)panel_x, (float)panel_y, (float)panel_width, (float)panel_height };

    Spacecraft* craft = &sim->spacecraft[render_state->selected_craft_index];

    // Create title with spacecraft name
    char title[128];
    snprintf(title, sizeof(title), "Maneuvers: %s", craft->name);

    // Draw window
    GuiWindowBox(panel_bounds, title);

    // Count maneuvers for this spacecraft
    int craft_maneuver_count = 0;
    for (int i = 0; i < sim->maneuver_count; i++) {
        if (sim->maneuvers[i].craft_index == render_state->selected_craft_index) {
            craft_maneuver_count++;
        }
    }

    if (craft_maneuver_count == 0) {
        // No maneuvers for this spacecraft
        Rectangle text_bounds = {
            (float)panel_x + 8,
            (float)panel_y + 25,
            (float)panel_width - 16,
            (float)panel_height - 29
        };
        GuiLabel(text_bounds, "No maneuvers defined");
        return;
    }

    // Create maneuver list string for raygui
    int buffer_size = craft_maneuver_count * (64 + 10 + 1) + 1;
    char* maneuver_list_text = (char*)malloc(buffer_size);
    if (!maneuver_list_text) return;

    maneuver_list_text[0] = '\0';
    int offset = 0;

    for (int i = 0; i < sim->maneuver_count; i++) {
        if (sim->maneuvers[i].craft_index == render_state->selected_craft_index) {
            if (offset > 0) {
                offset += snprintf(maneuver_list_text + offset, buffer_size - offset, ";");
            }

            const char* status_char = sim->maneuvers[i].executed ? "[DONE]" : "[PENDING]";
            offset += snprintf(maneuver_list_text + offset, buffer_size - offset, "%s %s",
                           status_char, sim->maneuvers[i].name);
        }
    }

    // Draw list view (inside window, leave space for title bar)
    Rectangle list_bounds = {
        (float)panel_x + 4,
        (float)panel_y + 25,
        (float)panel_width - 8,
        (float)panel_height - 100 // Leave space for details below
    };

    int maneuver_scroll = 0;
    int maneuver_active = -1;
    GuiListView(list_bounds, maneuver_list_text, &maneuver_scroll, &maneuver_active);

    // Show details for first pending or last executed maneuver
    char details_text[512];
    details_text[0] = '\0';

    for (int i = 0; i < sim->maneuver_count; i++) {
        if (sim->maneuvers[i].craft_index == render_state->selected_craft_index) {
            if (sim->maneuvers[i].executed) {
                snprintf(details_text, sizeof(details_text),
                         "Last executed:\n%s\nΔv: %.1f m/s\nTime: %.1f s",
                         sim->maneuvers[i].name, sim->maneuvers[i].delta_v, sim->maneuvers[i].executed_time);
            } else {
                snprintf(details_text, sizeof(details_text),
                         "Next pending:\n%s\nΔv: %.1f m/s",
                         sim->maneuvers[i].name, sim->maneuvers[i].delta_v);
                break; // Show first pending
            }
        }
    }

    if (details_text[0] != '\0') {
        Rectangle details_bounds = {
            (float)panel_x + 8,
            (float)panel_y + (float)panel_height - 70,
            (float)panel_width - 16,
            65
        };
        GuiLabel(details_bounds, details_text);
    }

    free(maneuver_list_text);
}