// ============================================================================
// block_interaction.c - 交互系统实现
// ============================================================================

#include "block_interaction.h"
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <Windows.h>

void interaction_init(BlockInteraction* inter) {
    memset(inter, 0, sizeof(BlockInteraction));
}

void interaction_mouse_move(BlockInteraction* inter, BlockWorkspace* ws, int x, int y) {
    inter->mouse_x = x;
    inter->mouse_y = y;
    
    // 拖拽积木
    if (inter->dragging_block) {
        float wx, wy;
        workspace_screen_to_world(ws, (float)x, (float)y, &wx, &wy);
        inter->dragging_block->x = wx - inter->drag_offset_x;
        inter->dragging_block->y = wy - inter->drag_offset_y;
    }
    
    // 平移画布
    if (inter->panning) {
        float dx = (x - inter->pan_start_x) / ws->zoom;
        float dy = (y - inter->pan_start_y) / ws->zoom;
        ws->view_x = inter->view_start_x - dx;
        ws->view_y = inter->view_start_y - dy;
    }
}

void interaction_mouse_down(BlockInteraction* inter, BlockWorkspace* ws, int button) {
    inter->mouse_down = 1;
    inter->mouse_button = button;
    
    float wx, wy;
    workspace_screen_to_world(ws, (float)inter->mouse_x, (float)inter->mouse_y, &wx, &wy);
    
    if (button == 0) {  // 左键
        // 检查是否点击槽位
        BlockSlot* slot = workspace_find_slot_at(ws, wx, wy);
        if (slot) {
            // 开始连接
            inter->connecting_from = slot;
            inter->connect_start_x = wx;
            inter->connect_start_y = wy;
            return;
        }
        
        // 检查是否点击积木
        Block* block = workspace_find_block_at(ws, wx, wy);
        if (block) {
            inter->dragging_block = block;
            inter->drag_offset_x = wx - block->x;
            inter->drag_offset_y = wy - block->y;
            inter->selected_block = block;
            ws->selected_block = block;
            return;
        }
        
        // 点击空白区域: 取消选择
        inter->selected_block = NULL;
        ws->selected_block = NULL;
    }
    
    if (button == 1 || button == 2) {  // 右键/中键: 平移
        inter->panning = 1;
        inter->pan_start_x = (float)inter->mouse_x;
        inter->pan_start_y = (float)inter->mouse_y;
        inter->view_start_x = ws->view_x;
        inter->view_start_y = ws->view_y;
    }
}

void interaction_mouse_up(BlockInteraction* inter, BlockWorkspace* ws, int button) {
    inter->mouse_down = 0;
    
    if (button == 0) {
        // 结束拖拽积木
        inter->dragging_block = NULL;
        
        // 结束连接
        if (inter->connecting_from) {
            float wx, wy;
            workspace_screen_to_world(ws, (float)inter->mouse_x, (float)inter->mouse_y, &wx, &wy);
            
            BlockSlot* target = workspace_find_slot_at(ws, wx, wy);
            if (target && target != inter->connecting_from) {
                // 尝试建立连接
                workspace_add_connection(ws, inter->connecting_from, target);
            }
            inter->connecting_from = NULL;
        }
    }
    
    if (button == 1 || button == 2) {
        inter->panning = 0;
    }
}

void interaction_key_down(BlockInteraction* inter, BlockWorkspace* ws, int key) {
    inter->key = key;
    inter->key_pressed = 1;
    
    // 删除选中的积木
    if (key == 46 || key == 8) {  // DELETE 或 BACKSPACE
        if (inter->selected_block) {
            workspace_remove_block(ws, inter->selected_block->id);
            inter->selected_block = NULL;
            ws->selected_block = NULL;
        }
    }
    
    // 复制/粘贴 (Ctrl+C / Ctrl+V)
    if (key == 'C' && (GetAsyncKeyState(VK_CONTROL) & 0x8000)) {
        // TODO: 复制到剪贴板
    }
    if (key == 'V' && (GetAsyncKeyState(VK_CONTROL) & 0x8000)) {
        // TODO: 从剪贴板粘贴
    }
}

void interaction_mouse_wheel(BlockInteraction* inter, BlockWorkspace* ws, int delta) {
    float zoom_factor = delta > 0 ? 1.1f : 0.9f;
    ws->zoom *= zoom_factor;
    if (ws->zoom < 0.25f) ws->zoom = 0.25f;
    if (ws->zoom > 4.0f) ws->zoom = 4.0f;
}

void interaction_update(BlockInteraction* inter, BlockWorkspace* ws) {
    inter->key_pressed = 0;
    (void)ws;
}