renderer.lua

local Renderer = {}

function Renderer.new(camera, grid, constants)
    local renderer = {
        camera = camera,
        grid = grid,
        colors = constants.colors
    }
    
    setmetatable(renderer, {__index = Renderer})
    return renderer
end

function Renderer:worldToScreen(worldX, worldY)
    return worldX + self.camera.x, worldY + self.camera.y
end

function Renderer:drawGrid()
    love.graphics.setColor(self.colors.grid)
    
    local w, h = love.graphics.getDimensions()
    local cellSize = self.grid.cellSize
    
    -- Calculate visible grid range
    local startX = math.max(0, math.floor(-self.camera.x / cellSize))
    local startY = math.max(0, math.floor(-self.camera.y / cellSize))
    local endX = math.min(self.grid.width, math.ceil((-self.camera.x + w) / cellSize))
    local endY = math.min(self.grid.height, math.ceil((-self.camera.y + h) / cellSize))
    
    -- Grid bounds in screen space
    local gridStartX = self.camera.x
    local gridStartY = self.camera.y
    local gridEndX = self.grid:getPixelWidth() + self.camera.x
    local gridEndY = self.grid:getPixelHeight() + self.camera.y
    
    -- Draw vertical lines
    for x = startX, endX do
        local screenX = x * cellSize + self.camera.x
        love.graphics.line(screenX, math.max(0, gridStartY), screenX, math.min(h, gridEndY))
    end
    
    -- Draw horizontal lines
    for y = startY, endY do
        local screenY = y * cellSize + self.camera.y
        love.graphics.line(math.max(0, gridStartX), screenY, math.min(w, gridEndX), screenY)
    end
end

function Renderer:drawPath(path, pathIndex)
    if #path == 0 then return end
    
    love.graphics.setColor(self.colors.path)
    for i = pathIndex, #path do
        self:drawCellAtPosition(path[i].x, path[i].y)
    end
end

function Renderer:drawCellAtPosition(cellX, cellY, color)
    local worldX, worldY = self.grid:cellToWorld(cellX, cellY)
    local screenX, screenY = self:worldToScreen(worldX, worldY)
    
    if color then
        love.graphics.setColor(color)
    end
    
    love.graphics.rectangle("fill", screenX, screenY, self.grid.cellSize, self.grid.cellSize)
end

function Renderer:drawUnit(unit)
    if not unit then return end
    love.graphics.setColor(self.colors.selectedUnit)
    self:drawCellAtPosition(unit.x, unit.y)
end

function Renderer:drawTargetCell(cell)
    if not cell then return end
    love.graphics.setColor(self.colors.targetCell)
    self:drawCellAtPosition(cell.x, cell.y)
end

return Renderer