store.v

module graphify

import os
import x.json2
import strings

// save_graph writes the graph to `path` as JSON using a manual builder —
// json2.encode's reflection is far too slow at graph scale (616s for vlang's
// full 100k-symbol graph).
//
// IMPORTANT: the CLI binary (cmd/cli, which calls this) must be built with
// `-gc none`. Boehm GC (V's `-prod` default) made this same encoder take
// 200s+ for a mere 16k symbols — some per-call GC bookkeeping in the hot
// write_string/write_u8 loop, not an allocation problem (verified: those
// calls are allocation-free, and stripping them to no-ops made the loop
// instant). Disabling GC entirely is safe here because graphify.exe only
// ever runs as a short-lived, one-shot process (extract, or a single query)
// that exits and lets the OS reclaim everything — do NOT apply -gc none to
// graphify-mcp.exe (cmd/mcp), which stays resident for a whole session.
pub fn save_graph(g Graph, path string) ! {
	os.write_file(path, graph_to_json(g))!
}

// load_graph reads a graph previously written by save_graph.
pub fn load_graph(path string) !Graph {
	content := os.read_file(path)!
	return json2.decode[Graph](content)!
}

// graph_to_json manually builds compact JSON for the graph. Every field write
// goes through write_string/write_u8/write_decimal (all allocation-free) to
// avoid string interpolation, which allocates a fresh string per call.
fn graph_to_json(g Graph) string {
	mut sb := strings.new_builder(g.symbols.len * 120 + g.edges.len * 60)
	sb.write_string('{"root":')
	write_json_str(mut sb, g.root)
	sb.write_string(',"symbols":[')
	for i, s in g.symbols {
		if i > 0 {
			sb.write_u8(`,`)
		}
		sb.write_string('{"id":')
		write_json_str(mut sb, s.id)
		sb.write_string(',"name":')
		write_json_str(mut sb, s.name)
		sb.write_string(',"kind":')
		sb.write_decimal(i64(s.kind))
		sb.write_string(',"signature":')
		write_json_str(mut sb, s.signature)
		sb.write_string(',"file":')
		write_json_str(mut sb, s.file)
		sb.write_string(',"line":')
		sb.write_decimal(i64(s.line))
		sb.write_string(',"end_line":')
		sb.write_decimal(i64(s.end_line))
		sb.write_string(',"is_pub":')
		sb.write_string(if s.is_pub { 'true' } else { 'false' })
		sb.write_string(',"parent":')
		write_json_str(mut sb, s.parent)
		sb.write_string(',"doc":')
		write_json_str(mut sb, s.doc)
		sb.write_u8(`}`)
	}
	sb.write_string('],"edges":[')
	for i, e in g.edges {
		if i > 0 {
			sb.write_u8(`,`)
		}
		sb.write_string('{"from":')
		write_json_str(mut sb, e.from)
		sb.write_string(',"to":')
		write_json_str(mut sb, e.to)
		sb.write_string(',"kind":')
		sb.write_decimal(i64(e.kind))
		sb.write_string(',"provenance":')
		sb.write_decimal(i64(e.provenance))
		sb.write_u8(`}`)
	}
	sb.write_string(']}')
	return sb.str()
}

// write_json_str writes a JSON-escaped string (with surrounding quotes) to sb.
fn write_json_str(mut sb strings.Builder, s string) {
	sb.write_u8(`"`)
	// fast path: no escaping needed (covers almost all ids, names, file paths)
	if !s.contains_any('"\\\n\r\t') {
		sb.write_string(s)
	} else {
		for b in s {
			match b {
				`"` { sb.write_string('\\"') }
				`\\` { sb.write_string('\\\\') }
				`\n` { sb.write_string('\\n') }
				`\r` { sb.write_string('\\r') }
				`\t` { sb.write_string('\\t') }
				else { sb.write_u8(b) }
			}
		}
	}
	sb.write_u8(`"`)
}