-- Mission IDs and debug phases are strings. Existing /prog still parses its
-- own arguments; this module is for future migration of that command.
local definitions = {
    ['crowbar:1'] = { contact = 'crowbar', number = 1, name = 'The Introduction', phases = { 'retrieve_vehicle', 'return_vehicle', 'complete' } },
    ['crowbar:2'] = { contact = 'crowbar', number = 2, name = 'Get Some Wheels', phases = { 'steal_vehicle', 'complete' } },
    ['crowbar:3'] = { contact = 'crowbar', number = 3, name = 'Quick Score', phases = { 'rob_register', 'lose_cops', 'complete' } },
    ['crowbar:4'] = { contact = 'crowbar', number = 4, name = 'Wash the Cash', phases = { 'meet_mack', 'meet_gabe', 'wash_cash', 'complete' } },
    ['crowbar:5'] = { contact = 'crowbar', number = 5, name = 'Buy In', phases = { 'get_package', 'escape_ambush', 'return_package', 'complete' } },
    ['mack:1'] = { contact = 'mack', number = 1, name = 'Easy Rider', phases = {} },
}

local M = { definitions = definitions }

function M.missionId(contact, number)
    if type(contact) ~= 'string' or not contact:match('^[a-z][a-z_]*$')
        or type(number) ~= 'number' or number % 1 ~= 0
        or number < 1 or number > 999
    then
        return nil
    end

    return ('%s:%d'):format(contact, number)
end

function M.phaseId(missionId, phaseName)
    if not definitions[missionId] or type(phaseName) ~= 'string'
        or not phaseName:match('^[a-z][a-z_]*$')
    then
        return nil
    end

    return missionId .. ':' .. phaseName
end

function M.parseProgPhase(contact, notation)
    if type(notation) ~= 'string' then return nil end

    local missionText, phaseText = notation:match('^(%d+)%.(%d+)$')
    if not missionText then return nil end
    if #missionText > 3 or #phaseText > 3 then return nil end

    local missionNumber, phaseNumber = tonumber(missionText), tonumber(phaseText)
    if not missionNumber or not phaseNumber or missionNumber < 1 or phaseNumber < 1 then
        return nil
    end

    local id = M.missionId(contact, missionNumber)
    local definition = definitions[id]
    local phaseName = definition and definition.phases[phaseNumber]
    if not phaseName then return nil end

    return {
        missionId = id,
        phaseId = M.phaseId(id, phaseName),
        missionNumber = missionNumber,
        phaseNumber = phaseNumber,
        phaseName = phaseName,
        notation = notation,
    }
end

return M