-- lib-core.inventory-list-display-test — v0.1.0
-- 9 assertions covering widget creation, action lifecycle, resolver
-- overrides, and content ordering.
-- Pattern follows P.2.4 Test-Module-Pattern; TAP output via engine.test.*

local panel       = require("lib-core.panel")
local composition = require("lib-core.composition")
local inventory   = require("lib-core.inventory-list")
local display     = require("lib-core.inventory-list-display")
local T = engine.test

local M = {}

-- ----------------------------------------------------------------
-- Template definitions (shared across all assertions in this run)
-- All template IDs are unique to this test lib to avoid clashes.
-- ----------------------------------------------------------------

-- Container template: kind="list", no constraints.
composition.define_template{
    id = "test_backpack",
    properties = { position = {x = 0, y = 0} },
    tags = {"renderable"},
    container = { kind = "list" },
}

-- Item template: individual stack_mode + Atlas-UV properties for icon tests.
composition.define_template{
    id = "test_item",
    properties = {
        stack_mode   = "individual",
        sprite_atlas = "tex.png",
        sprite_uv    = {x = 0, y = 0, w = 8, h = 8},
        position     = {x = 0, y = 0},
    },
    tags = {"renderable", "item"},
}

function M.run_tests(ctx)
    local bp = composition.create{template = "test_backpack"}

    -- ================================================================
    -- 1. create returns widget_def with render + handle_input + title
    -- ================================================================

    local widget = display.create(bp, { title = "Backpack" })
    T.assert(widget ~= nil, "create returns non-nil")
    T.equals(type(widget.render), "function", "widget has render fn")
    T.equals(type(widget.handle_input), "function", "widget has handle_input")
    T.equals(widget.title, "Backpack", "title set from opts")

    -- ================================================================
    -- 2. create with non-container entity -> loud-error
    -- test_item has no container block, so composition.get_container
    -- returns nil, and display.create loud-errors.
    -- ================================================================

    local plain = composition.create{template = "test_item"}
    local ok2 = pcall(display.create, plain)
    T.assert(not ok2, "create(non_container) loud-errors")

    -- ================================================================
    -- 3. register_action + unregister_action round-trip (no error)
    -- ================================================================

    display.register_action(widget, "Drop", function(item, c) end)
    display.register_action(widget, "Inspect", function(item, c) end)
    display.unregister_action(widget, "Drop")
    T.assert(true, "register/unregister round-trip completes without error")

    -- ================================================================
    -- 4. Duplicate action label -> loud-error
    -- "Drop" was unregistered above; re-register then attempt duplicate.
    -- ================================================================

    display.register_action(widget, "Drop", function() end)
    local ok4 = pcall(display.register_action, widget, "Drop", function() end)
    T.assert(not ok4, "duplicate action label loud-errors")

    -- ================================================================
    -- 5. Non-function callback -> loud-error
    -- ================================================================

    local ok5 = pcall(display.register_action, widget, "X", "not_fn")
    T.assert(not ok5, "non-function callback loud-errors")

    -- ================================================================
    -- 6. Default action-set is empty; unregister of unknown label is no-op
    -- A fresh widget has no implicit actions. Unregistering a missing
    -- label must not error (idempotent).
    -- ================================================================

    local widget2 = display.create(composition.create{template = "test_backpack"})
    display.unregister_action(widget2, "Drop")   -- no-op: not registered
    T.assert(true, "default action-set empty; unregister of unknown label is no-op")

    -- ================================================================
    -- 7. Rows match inventory.contents order (_test_get_rows)
    -- ================================================================

    local item_a = composition.create{template = "test_item"}
    local item_b = composition.create{template = "test_item"}
    inventory.add(bp, item_a)
    inventory.add(bp, item_b)
    local rows = display._test_get_rows(widget)
    T.assert(#rows == 2, "rows reflect inventory.contents count")

    -- Verify ordering: item_a was added first, must appear first.
    -- Compare by composition.reg_id (stable identity; entity userdata has no __eq).
    local rid_a = item_a:get_property("composition.reg_id")
    local rid_r1 = rows[1]:get_property("composition.reg_id")
    T.assert(rid_a ~= nil and rid_r1 == rid_a,
        "rows[1] matches item_a (insertion order preserved)")

    -- ================================================================
    -- 8. Default icon-resolver reads sprite_atlas + sprite_uv from properties
    -- ================================================================

    local icon = display._test_resolve_icon(widget, item_a)
    T.assert(icon ~= nil, "default icon-resolver returns non-nil table")
    T.equals(icon.atlas, "tex.png", "icon.atlas matches sprite_atlas property")
    T.equals(icon.uv.x, 0, "icon.uv.x matches sprite_uv.x property")

    -- ================================================================
    -- 9. Custom icon-resolver invoked after set_icon_resolver
    -- ================================================================

    local custom_called = false
    display.set_icon_resolver(widget, function(item)
        custom_called = true
        return {atlas = "custom.png", uv = {x = 1, y = 2, w = 3, h = 4}}
    end)
    local icon2 = display._test_resolve_icon(widget, item_a)
    T.assert(custom_called, "custom icon-resolver was invoked after set_icon_resolver")
    T.equals(icon2.atlas, "custom.png", "custom resolver returns custom atlas")
end

return M