local input = require("lib-core.input")
-- fsm.lua lives in this module's dir; engine_lua_lib's searcher only resolves
-- declared lib-deps, so multi-file modules use dofile + engine.module.dir_of.
local fsm = dofile(engine.module.dir_of("lib-sporel.launcher") .. "/fsm.lua")

local STATE_LIST, STATE_QUIT, EXIT = fsm.STATE_LIST, fsm.STATE_QUIT_CONFIRM, fsm.EXIT
local state = STATE_LIST

local modules        = {}    -- [{id, version, name, rect={x,y,w,h}}]
local quit_buttons   = {}    -- {yes = rect, no = rect}
local screen_w, screen_h   -- queried in init() via engine.window.size() (P.3.5)

-- CI-conditional self-exit (matches spine-prototype's pattern).
-- Interactive runs (no SPOREL_CI=1) loop until ESC or quit-confirm.
local frames = 0
local CI_FRAMES = 60

local TITLE        = "Sporel Launcher"
local QUIT_PROMPT  = "Sporel beenden?"
local YES_LABEL    = "Ja"
local NO_LABEL     = "Nein"
local EMPTY_LABEL  = "Keine Module installiert."

local FONT_TITLE   = 28
local FONT_BUTTON  = 20
local PAD_X        = 16
local PAD_Y        = 8

local COLOR_BG     = 0x202020FF
local COLOR_BTN    = 0x404040FF
local COLOR_HOVER  = 0x606060FF
local COLOR_TEXT   = 0xE0E0E0FF
local COLOR_DIM    = 0x000000B4   -- semi-transparent overlay
local COLOR_MODAL  = 0x303030FF

local hit = engine.spatial.aabb_contains_point

function init(ctx)
    screen_w, screen_h = engine.window.size()
    local list = engine.module.list()
    local y = 80
    for i, m in ipairs(list) do
        local label = m.name or m.id
        local w, h  = engine.render.measure_text(label, FONT_BUTTON)
        local btn_w = w + 2 * PAD_X
        local btn_h = h + 2 * PAD_Y
        modules[i] = {
            id      = m.id,
            version = m.version,
            name    = label,
            rect    = { x = (screen_w - btn_w) / 2, y = y, w = btn_w, h = btn_h }
        }
        y = y + btn_h + 8
    end

    local wy, hy = engine.render.measure_text(YES_LABEL, FONT_BUTTON)
    local wn, hn = engine.render.measure_text(NO_LABEL,  FONT_BUTTON)
    local btn_w  = math.max(wy, wn) + 2 * PAD_X
    local btn_h  = math.max(hy, hn) + 2 * PAD_Y
    local total_w = 2 * btn_w + 24
    quit_buttons.yes = { x = (screen_w - total_w) / 2,                y = screen_h / 2 + 24, w = btn_w, h = btn_h }
    quit_buttons.no  = { x = (screen_w - total_w) / 2 + btn_w + 24,   y = screen_h / 2 + 24, w = btn_w, h = btn_h }

    input.bind("ui_click",   { "mouse_left" })
    input.bind("ui_back",    { "escape" })
    input.bind("ui_confirm", { "enter" })

    engine.print(string.format("launcher: init ok, modules=%d", #modules))
end

function update(ctx, dt)
    frames = frames + 1
    if os.getenv("SPOREL_CI") == "1" and frames >= CI_FRAMES then
        engine.exit(0)
        return
    end

    local mx, my = engine.input.get_mouse_pos()

    if state == STATE_LIST then
        if input.was_action_pressed("ui_back") then
            state = fsm.next(state, "esc")
        elseif input.was_action_pressed("ui_click") then
            for _, m in ipairs(modules) do
                if hit(m.rect, mx, my) then
                    engine.switch_module(m.id)
                    return
                end
            end
        end
    elseif state == STATE_QUIT then
        if input.was_action_pressed("ui_back") then
            state = fsm.next(state, "esc")
        elseif input.was_action_pressed("ui_confirm") then
            engine.exit(0); return
        elseif input.was_action_pressed("ui_click") then
            if hit(quit_buttons.yes, mx, my) then
                engine.exit(0); return
            elseif hit(quit_buttons.no, mx, my) then
                state = fsm.next(state, "click_no")
            end
        end
    end
end

function render(ctx)
    local mx, my = engine.input.get_mouse_pos()

    engine.render.clear_color(COLOR_BG)
    local tw = engine.render.measure_text(TITLE, FONT_TITLE)
    engine.render.draw_text(TITLE, (screen_w - tw) / 2, 24, FONT_TITLE, COLOR_TEXT)

    if #modules == 0 then
        local ew = engine.render.measure_text(EMPTY_LABEL, FONT_BUTTON)
        engine.render.draw_text(EMPTY_LABEL, (screen_w - ew) / 2, screen_h / 2, FONT_BUTTON, COLOR_TEXT)
    else
        for _, m in ipairs(modules) do
            local color = hit(m.rect, mx, my) and COLOR_HOVER or COLOR_BTN
            engine.render.draw_rect(m.rect.x, m.rect.y, m.rect.w, m.rect.h, color)
            local lw = engine.render.measure_text(m.name, FONT_BUTTON)
            engine.render.draw_text(m.name, m.rect.x + (m.rect.w - lw) / 2, m.rect.y + PAD_Y, FONT_BUTTON, COLOR_TEXT)
        end
    end

    if state == STATE_QUIT then
        engine.render.draw_rect(0, 0, screen_w, screen_h, COLOR_DIM)
        local modal_w, modal_h = 360, 140
        engine.render.draw_rect((screen_w - modal_w) / 2, (screen_h - modal_h) / 2, modal_w, modal_h, COLOR_MODAL)
        local pw = engine.render.measure_text(QUIT_PROMPT, FONT_BUTTON)
        engine.render.draw_text(QUIT_PROMPT, (screen_w - pw) / 2, screen_h / 2 - 24, FONT_BUTTON, COLOR_TEXT)

        for _, key in ipairs({ "yes", "no" }) do
            local b = quit_buttons[key]
            local color = hit(b, mx, my) and COLOR_HOVER or COLOR_BTN
            engine.render.draw_rect(b.x, b.y, b.w, b.h, color)
            local label = (key == "yes") and YES_LABEL or NO_LABEL
            local lw = engine.render.measure_text(label, FONT_BUTTON)
            engine.render.draw_text(label, b.x + (b.w - lw) / 2, b.y + PAD_Y, FONT_BUTTON, COLOR_TEXT)
        end
    end
end

function cleanup(ctx)
    engine.print("launcher: cleanup")
end