local robot = require("robot")
local nav = require("navigator")

local function mine_single()
    robot.swing()

    local result, error = robot.forward()
    if not result then
        print("Cannot move: " .. error)
        return false
    end

    robot.swingUp()

    return true
end

local function mine_n(count)
    local mined = 0
    for _ = 1, count do
        if mine_single() then
            mined = mined + 1
        else
            break
        end
    end
    return mined
end

local function mine_row(length)
    local mined = mine_n(length)

    robot.turnAround()

    nav.forward(mined, true)
end

-- starts facing right, mines rows to the right
-- ends facing "left"
local function mine(mine_rows, mine_row_length)
    local moved_rows = nav.forward_until_solid()
    for i = 1, mine_rows do
        print("Mining row " .. i .. " of " .. mine_rows)
        if mine_n(1) ~= 1 then
            print("Unable to continue mining rows")
            break
        end
        robot.turnLeft()
        mine_row(mine_row_length)
        moved_rows = moved_rows + 1
        robot.turnLeft()
    end

    -- go back to start
    robot.turnAround()
    nav.forward(moved_rows, true)
end

return {
    mine = mine
}