-- Base building materials for the clone.
--
-- The engine reads the global `Materials` array (in order). Build modes 1-4
-- map to entries 1-4. Mods under data/mods/ run AFTER this file and may use
-- FindMaterial(name) to tweak these, or table.insert(Materials, ...) to add new
-- ones. (angle_threshold is in DEGREES; the engine converts to radians.)

Materials =
{
    {
        name = "wood",
        stiffness = 600, damping = 12, mass = 0.25,
        max_compression = 0.90, max_expansion = 1.10,  -- snaps past +/-10% length
        angle_threshold = 30, tension_only = false,    -- snaps if a loose strut rotates >30deg
        min_length = 0.4, max_length = 3.0, max_link_length = 6.0,  -- single-strut size limits
        hit_points = 150,
        flammable = true, burn_rate = 15, spread_time = 2.0,   -- wood: slow burn/spread
        blocks_projectiles = true, blocks_beam = true,         -- solid: stops shells & beams
        half_width = 0.15,
        cost_metal = 5, cost_energy = 25,               -- Forts wood 0.1 / 0.5
        color = { 1.0, 1.0, 1.0, 1.0 },                 -- white = show texture untinted
        texture = "data/textures/wood.png",
        texture_forts = "forts:materials/wood_panel.tga",
    },
    {
        name = "bgbrace",                               -- background bracing
        stiffness = 600, damping = 12, mass = 0.25,
        max_compression = 0.92, max_expansion = 1.08,
        angle_threshold = 30, tension_only = false,
        min_length = 0.4, max_length = 3.0, max_link_length = 6.0,
        hit_points = 100,
        flammable = true, burn_rate = 22, spread_time = 0.7,   -- burns ~3x faster than wood
        blocks_projectiles = false, blocks_beam = false,       -- shells AND beams pass through (beam still burns it)
        half_width = 0.15,
        cost_metal = 5, cost_energy = 25,
        color = { 1.0, 1.0, 1.0, 0.45 },                -- translucent
        texture = "data/textures/bgbrace.png",
        texture_forts = "forts:materials/bracing-bg.tga",
    },
    {
        name = "rope",
        stiffness = 150, damping = 8, mass = 0.05,
        max_compression = 0.0, max_expansion = 1.50,    -- slack in compression, snaps at +50%
        angle_threshold = 360, tension_only = true,     -- never snaps on angle
        min_length = 0.8, max_length = 1.5, max_link_length = 20.0,  -- subdivides into many segments -> drapes
        hit_points = 50,
        flammable = true, burn_rate = 25, spread_time = 1.0,   -- burns through fast
        blocks_projectiles = false, blocks_beam = false,       -- shells AND beams pass through
        half_width = 0.04,
        cost_metal = 5, cost_energy = 25,
        color = { 0.72, 0.66, 0.55, 1.0 },   -- tan: tints the cable art, and is
                                             -- the visible rope when it is absent
        texture_forts = "forts:materials/cable.tga",
    },
    -- Appended LAST on purpose: build modes map to this array by index, so a new
    -- material goes on the end (key 4) rather than shifting bg-brace and rope.
    {
        name = "armour",                                -- the kinetic tank
        -- Forts armor: 25% stiffer than wood, 2x the mass, HP 400, and it does
        -- NOT catch fire (its Fire deg/s is n/a). 3 wood (450 HP) still beats
        -- 1 armour (400 HP), so armour buys durability per strut, not per metal.
        stiffness = 750, damping = 12, mass = 0.5,
        max_compression = 0.90, max_expansion = 1.10,   -- same +/-10% as wood
        angle_threshold = 30, tension_only = false,
        min_length = 0.4, max_length = 3.0, max_link_length = 6.0,
        hit_points = 400,
        flammable = false, burn_rate = 0, spread_time = 0,   -- metal: never burns
        blocks_projectiles = true, blocks_beam = true,       -- solid
        half_width = 0.18,                              -- reads chunkier than wood
        cost_metal = 90, cost_energy = 75,              -- Forts 1.8 / 1.5, i.e.
                                                        -- 18x wood metal, 3x energy
        color = { 0.62, 0.66, 0.70, 1.0 },              -- steel (also the fallback)
        texture_forts = "forts:materials/armor.tga",
    },
}

-- Helpers mods can use (mirrors the Forts modding API shape).
function IndexOfMaterial(name)
    for i, m in ipairs(Materials) do
        if m.name == name then return i end
    end
    return nil
end

function FindMaterial(name)
    local i = IndexOfMaterial(name)
    if i then return Materials[i] end
    return nil
end