-- =====================================================================
-- lib-core.input — Action-Mapping + Direction-Vector (P.0)
-- See: meta/docs/superpowers/specs/2026-05-09-p0-lib-input-design.md
--
-- Scope: action-mapping (key-arrays per action) + direction-vector helper.
-- DEPRECATED-MVP for: mouse-button actions, gamepad bindings, action-
-- context-stack, key-rebinding config, modifier-combos, analog-axis,
-- was_action_released edge.
-- =====================================================================

local bindings = {}  -- action_name -> array of key-codes

local M = {}

function M.bind(action_name, keys)
    if type(action_name) ~= "string" then
        error("input.bind: action_name must be a string")
    end
    if type(keys) ~= "table" or #keys == 0 then
        error(string.format("input.bind: keys must be a non-empty array of key-codes (action '%s')",
            action_name))
    end
    bindings[action_name] = keys
end

function M.unbind(action_name)
    bindings[action_name] = nil
end

function M.is_action_down(action_name)
    local keys = bindings[action_name]
    if not keys then return false end
    for _, k in ipairs(keys) do
        if engine.input.is_key_down(k) then return true end
    end
    return false
end

function M.was_action_pressed(action_name)
    local keys = bindings[action_name]
    if not keys then return false end
    for _, k in ipairs(keys) do
        if engine.input.was_pressed(k) then return true end
    end
    return false
end

-- Direction-vector helper: returns {x, y} in {-1, 0, +1} each axis.
-- Y-down-positive per Sporel pixel-convention (ADR-0031).
function M.direction(left_action, right_action, up_action, down_action)
    local x = (M.is_action_down(right_action) and 1 or 0)
            - (M.is_action_down(left_action)  and 1 or 0)
    local y = (M.is_action_down(down_action)  and 1 or 0)
            - (M.is_action_down(up_action)    and 1 or 0)
    return { x = x, y = y }
end

function M.action_count()
    local n = 0
    for _ in pairs(bindings) do n = n + 1 end
    return n
end

-- DEPRECATED-MVP: bind_mouse(action, button)         -- mouse-button slice
-- DEPRECATED-MVP: bind_gamepad(action, ...)           -- gamepad slice
-- DEPRECATED-MVP: push_context(name) / pop_context()  -- action-context-stack
-- DEPRECATED-MVP: load_bindings_from_config(path)     -- key-rebinding slice
-- DEPRECATED-MVP: was_action_released(action)         -- lift-detection slice

return M