library(shiny)
library(shinyjs)

# Simple configuration
CONFIG <- list(
  tile_size = 150,
  shuffle_moves = 100
)

source("minimal_global.R")

# UI
ui <- fluidPage(
  useShinyjs(),
  titlePanel(title = NULL, windowTitle = "Puzzle8"), 
  tags$head(
    tags$meta(name = "viewport", content = "width=device-width, initial-scale=1"),
    tags$style(HTML("
      :root {
        --tile-size: 150px;
        --primary-color: #2196F3;
        --success-color: #4CAF50;
        --warning-color: #FF9800;
        --border-radius: 8px;
        --shadow-light: 0 2px 4px rgba(0,0,0,0.1);
        --shadow-medium: 0 4px 8px rgba(0,0,0,0.15);
        --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      }
      
      body {
        font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        min-height: 100vh;
        margin: 0;
        padding: 20px 0;
      }
      
      .container-fluid {
        max-width: 800px;
        margin: 0 auto;
      }
      
      .game-container {
        background: rgba(255, 255, 255, 0.95);
        border-radius: 16px;
        box-shadow: 0 20px 40px rgba(0,0,0,0.1);
        backdrop-filter: blur(10px);
        padding: 30px;
        margin: 20px;
        text-align: center;
      }
      
      .puzzle-grid {
        display: grid;
        grid-template-columns: repeat(3, var(--tile-size));
        grid-template-rows: repeat(3, var(--tile-size));
        gap: 8px;
        justify-content: center;
        margin: 30px auto;
        padding: 20px;
        background: rgba(0,0,0,0.05);
        border-radius: var(--border-radius);
      }
      
      .puzzle-tile {
        width: var(--tile-size);
        height: var(--tile-size);
        border: none;
        border-radius: var(--border-radius);
        background: linear-gradient(145deg, var(--primary-color), #1976D2);
        color: white;
        font-size: 32px;
        font-weight: 700;
        display: flex;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        transition: var(--transition);
        box-shadow: var(--shadow-light);
        position: relative;
        overflow: hidden;
      }
      
      .puzzle-tile::before {
        content: '';
        position: absolute;
        top: 0;
        left: -100%;
        width: 100%;
        height: 100%;
        background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
        transition: left 0.5s;
      }
      
      .puzzle-tile:hover::before {
        left: 100%;
      }
      
      .puzzle-tile:hover {
        transform: translateY(-2px) scale(1.02);
        box-shadow: var(--shadow-medium);
      }
      
      .puzzle-tile:active {
        transform: translateY(0) scale(0.98);
      }
      
      .empty-tile {
        background: rgba(255,255,255,0.8);
        border: 2px dashed #ccc;
        box-shadow: inset 0 2px 4px rgba(0,0,0,0.1);
      }
      
      .moves-counter {
        background: white;
        padding: 20px;
        border-radius: var(--border-radius);
        margin: 20px 0;
        box-shadow: var(--shadow-light);
        border-left: 4px solid var(--primary-color);
      }
      
      .congratulations-card {
        background: linear-gradient(145deg, #4CAF50, #388E3C);
        color: white;
        padding: 25px;
        border-radius: var(--border-radius);
        margin: 20px 0;
        box-shadow: var(--shadow-medium);
        animation: celebration 0.6s ease;
        border: none;
      }
      
      @keyframes celebration {
        0% {
          opacity: 0;
          transform: translateY(-20px) scale(0.9);
        }
        50% {
          transform: translateY(-5px) scale(1.05);
        }
        100% {
          opacity: 1;
          transform: translateY(0) scale(1);
        }
      }
      
      .moves-value {
        font-size: 36px;
        font-weight: bold;
        color: var(--primary-color);
        margin-bottom: 5px;
      }
      
      .moves-label {
        font-size: 14px;
        color: #666;
        text-transform: uppercase;
        letter-spacing: 1px;
      }
      
      .congratulations-title {
        font-size: 28px;
        font-weight: bold;
        margin-bottom: 10px;
        display: flex;
        align-items: center;
        justify-content: center;
        gap: 10px;
      }
      
      .congratulations-subtitle {
        font-size: 18px;
        font-weight: 600;
        opacity: 0.9;
      }
      
      .btn-game {
        padding: 15px 30px;
        border: none;
        border-radius: var(--border-radius);
        font-weight: 600;
        font-size: 16px;
        cursor: pointer;
        transition: var(--transition);
        text-transform: uppercase;
        letter-spacing: 0.5px;
        margin: 10px;
        min-width: 140px;
      }
      
      .btn-success {
        background: linear-gradient(145deg, var(--success-color), #388E3C);
        color: white;
      }
      
      .btn-warning {
        background: linear-gradient(145deg, var(--warning-color), #F57C00);
        color: white;
      }
      
      .btn-game:hover {
        transform: translateY(-2px);
        box-shadow: var(--shadow-medium);
      }
      
      .victory-message {
        background: linear-gradient(145deg, #4CAF50, #388E3C);
        color: white;
        padding: 25px;
        border-radius: var(--border-radius);
        margin: 20px 0;
        font-size: 18px;
        font-weight: 600;
        box-shadow: var(--shadow-medium);
        animation: slideIn 0.5s ease;
      }
      
      @keyframes slideIn {
        from {
          opacity: 0;
          transform: translateY(-20px);
        }
        to {
          opacity: 1;
          transform: translateY(0);
        }
      }
      
      .instructions {
        background: white;
        border-radius: var(--border-radius);
        padding: 25px;
        box-shadow: var(--shadow-light);
        text-align: left;
        margin: 20px 0;
      }
      
      .instructions h3 {
        color: var(--primary-color);
        margin-bottom: 15px;
        font-weight: 600;
        text-align: center;
      }
      
      .instructions ul {
        padding-left: 20px;
      }
      
      .instructions li {
        margin-bottom: 8px;
        line-height: 1.5;
      }
      
      .goal-grid {
        display: grid;
        grid-template-columns: repeat(3, 50px);
        gap: 5px;
        justify-content: center;
        margin: 15px 0;
      }
      
      .goal-tile {
        width: 50px;
        height: 50px;
        background: var(--primary-color);
        color: white;
        display: flex;
        align-items: center;
        justify-content: center;
        border-radius: 4px;
        font-weight: bold;
        font-size: 16px;
      }
      
      .goal-empty {
        background: #f0f0f0;
        border: 2px dashed #ccc;
      }
      
      /* Responsive Design */
      @media (max-width: 768px) {
        :root {
          --tile-size: 100px;
        }
        
        .game-container {
          margin: 10px;
          padding: 20px;
        }
        
        .puzzle-tile {
          font-size: 24px;
        }
        
        .moves-value {
          font-size: 28px;
        }
        
        .congratulations-title {
          font-size: 24px;
        }
        
        .congratulations-subtitle {
          font-size: 16px;
        }
        
        .btn-game {
          min-width: auto;
          padding: 12px 20px;
          font-size: 14px;
        }
      }
      
      @media (max-width: 480px) {
        :root {
          --tile-size: 80px;
        }
        
        .puzzle-tile {
          font-size: 20px;
        }
        
        .moves-value {
          font-size: 24px;
        }
        
        .congratulations-title {
          font-size: 20px;
        }
        
        .congratulations-subtitle {
          font-size: 14px;
        }
      }
    "))
  ),
  
  div(class = "container-fluid",
    div(class = "game-container",
      # Title
      h1("🧩 Puzzle8", 
         style = "background: linear-gradient(145deg, #2196F3, #1976D2); 
                  -webkit-background-clip: text; -webkit-text-fill-color: transparent; 
                  font-weight: 800; font-size: 3rem; margin-bottom: 30px;"),
      
      # Dynamic Counter/Congratulations Card
      uiOutput("status_card"),
      
      # Puzzle Grid
      div(class = "puzzle-grid",
        lapply(1:9, function(i) {
          div(id = paste0("tile_container_", i), uiOutput(paste0("tile_", i)))
        })
      ),
      
      # Control Buttons
      div(class = "text-center",
        actionButton("new_game", "New Game", class = "btn-game btn-success"),
        actionButton("reset_game", "Reset", class = "btn-game btn-warning")
      ),
      
      # Instructions
      div(class = "instructions",
        h3("🎯 How to Play"),
        p("Arrange numbers 1-8 in order with the empty space in the bottom-right corner."),
        tags$ul(
          tags$li("Click on tiles adjacent to the empty space to move them"),
          tags$li("Only tiles next to the empty space can be moved"),
          tags$li("Try to solve the puzzle in as few moves as possible!")
        ),
        
        div(style = "text-align: center; margin-top: 20px;",
          h4("🏆 Goal:"),
          div(class = "goal-grid",
            lapply(1:8, function(i) {
              div(class = "goal-tile", i)
            }),
            div(class = "goal-tile goal-empty")
          )
        )
      )
    )
  )
)

# Server
server <- function(input, output, session) {
  # Simple game state
  game_state <- reactiveValues(
    puzzle = NULL,
    initial_puzzle = NULL,
    moves = 0,
    game_won = FALSE
  )
  
  # Initialize game
  observe({
    if(is.null(game_state$puzzle)) {
      new_puzzle <- create_solvable_puzzle()
      game_state$puzzle <- new_puzzle
      game_state$initial_puzzle <- new_puzzle
    }
  })
  
  # Tile click handlers
  observe({
    lapply(1:9, function(i) {
      observeEvent(input[[paste0("tile_", i)]], {
        if(!game_state$game_won && !is.null(game_state$puzzle)) {
          result <- move_tile(game_state$puzzle, i)
          
          if(result$moved) {
            game_state$puzzle <- result$puzzle
            game_state$moves <- game_state$moves + 1
            
            # Check win condition
            if(is_solved(game_state$puzzle)) {
              game_state$game_won <- TRUE
              # showNotification(
              #   paste("🎉 Congratulations! Solved in", game_state$moves, "moves!"), 
              #   type = "message", duration = 5
              # )
            }
          }
        }
      })
    })
  })
  
  # New Game button
  observeEvent(input$new_game, {
    new_puzzle <- create_solvable_puzzle()
    game_state$puzzle <- new_puzzle
    game_state$initial_puzzle <- new_puzzle
    game_state$moves <- 0
    game_state$game_won <- FALSE
    
    # showNotification("New game started!", type = "message")
  })
  
  # Reset button
  observeEvent(input$reset_game, {
    if(!is.null(game_state$initial_puzzle)) {
      game_state$puzzle <- game_state$initial_puzzle
      game_state$moves <- 0
      game_state$game_won <- FALSE
      
      # showNotification("Game reset!", type = "message")
    }
  })
  
  # Render tiles
  lapply(1:9, function(i) {
    output[[paste0("tile_", i)]] <- renderUI({
      req(game_state$puzzle)
      
      value <- game_state$puzzle[i]
      
      if(value == 0) {
        div(class = "empty-tile")
      } else {
        actionButton(
          paste0("tile_", i),
          label = as.character(value),
          class = "puzzle-tile"
        )
      }
    })
  })
  
  # Dynamic Status Card (Moves Counter or Congratulations)
  output$status_card <- renderUI({
    if(game_state$game_won) {
      # Congratulations Card
      div(class = "congratulations-card",
        div(class = "congratulations-title",
          "🏆 Congratulations!"
        ),
        div(class = "congratulations-subtitle",
          paste("Puzzle solved in", game_state$moves, "moves!")
        )
      )
    } else {
      # Moves Counter Card
      div(class = "moves-counter",
        div(class = "moves-value", game_state$moves),
        div(class = "moves-label", "Moves")
      )
    }
  })
}

# Run the application
shinyApp(ui = ui, server = server)