// Copyright (c) 2026 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
// vtest build: macos
//
// Parity pin for the final build_expr_from_flat sweep after s197. The fixture
// intentionally mixes value-producing arms (postfix, array init, string
// interpolation, call-or-cast, as-cast, tuple, or, fn literal) with legacy
// zero-fallback arms (range, map, match, assoc, if-guard, comptime, generic,
// lambda, lifetime, lock, select, sql).
module ssa

import v2.ast
import v2.token
import v2.types

fn rem_ident(name string) ast.Expr {
    return ast.Expr(ast.Ident{
        name: name
    })
}

fn rem_num(value string) ast.Expr {
    return ast.Expr(ast.BasicLiteral{
        kind:  .number
        value: value
    })
}

fn rem_ret_fn(name string, expr ast.Expr) ast.Stmt {
    return ast.Stmt(ast.FnDecl{
        name:  name
        typ:   ast.FnType{
            return_type: rem_ident('int')
        }
        stmts: [
            ast.Stmt(ast.ReturnStmt{
                exprs: [expr]
            }),
        ]
    })
}

fn rem_expr_fn(name string, expr ast.Expr) ast.Stmt {
    return ast.Stmt(ast.FnDecl{
        name:  name
        typ:   ast.FnType{}
        stmts: [
            ast.Stmt(ast.ExprStmt{
                expr: expr
            }),
        ]
    })
}

fn make_remaining_expr_fixture() []ast.File {
    mut stmts := [
        ast.Stmt(ast.ModuleStmt{
            name: 'main'
        }),
    ]
    stmts << rem_ret_fn('keyword_true', ast.Expr(ast.Keyword{
        tok: .key_true
    }))
    stmts << rem_ret_fn('sizeof_int', ast.Expr(ast.KeywordOperator{
        op:    .key_sizeof
        exprs: [rem_ident('int')]
    }))
    stmts << ast.Stmt(ast.FnDecl{
        name:  'postfix_inc'
        typ:   ast.FnType{
            return_type: rem_ident('int')
        }
        stmts: [
            ast.Stmt(ast.AssignStmt{
                op:  .decl_assign
                lhs: [rem_ident('x')]
                rhs: [rem_num('1')]
            }),
            ast.Stmt(ast.ExprStmt{
                expr: ast.Expr(ast.PostfixExpr{
                    op:   .inc
                    expr: rem_ident('x')
                })
            }),
            ast.Stmt(ast.ReturnStmt{
                exprs: [rem_ident('x')]
            }),
        ]
    })
    stmts << rem_expr_fn('array_literal', ast.Expr(ast.ArrayInitExpr{
        exprs: [rem_num('1'), rem_num('2')]
    }))
    stmts << rem_expr_fn('string_inter', ast.Expr(ast.StringInterLiteral{
        kind:   .v
        values: ["'hi'"]
    }))
    stmts << rem_ret_fn('or_inner', ast.Expr(ast.OrExpr{
        expr: rem_num('9')
    }))
    stmts << rem_expr_fn('anon_fn', ast.Expr(ast.FnLiteral{
        typ: ast.FnType{}
    }))
    stmts << rem_ret_fn('call_or_cast', ast.Expr(ast.CallOrCastExpr{
        lhs:  rem_ident('int')
        expr: rem_num('7')
    }))
    stmts << rem_ret_fn('as_cast', ast.Expr(ast.AsCastExpr{
        expr: rem_num('8')
        typ:  rem_ident('int')
    }))
    stmts << rem_ret_fn('tuple_first', ast.Expr(ast.Tuple{
        exprs: [rem_num('3'), rem_num('4')]
    }))
    stmts << rem_ret_fn('map_zero', ast.Expr(ast.MapInitExpr{
        keys: [rem_num('1')]
        vals: [rem_num('2')]
    }))
    stmts << rem_ret_fn('range_zero', ast.Expr(ast.RangeExpr{
        op:    .dotdot
        start: rem_num('0')
        end:   rem_num('3')
    }))
    stmts << rem_ret_fn('match_zero', ast.Expr(ast.MatchExpr{
        expr: rem_num('1')
    }))
    stmts << rem_ret_fn('assoc_zero', ast.Expr(ast.AssocExpr{
        typ:  rem_ident('Point')
        expr: rem_ident('p')
    }))
    stmts << rem_ret_fn('if_guard_zero', ast.Expr(ast.IfGuardExpr{
        stmt: ast.AssignStmt{
            op:  .decl_assign
            lhs: [rem_ident('x')]
            rhs: [rem_num('1')]
        }
    }))
    stmts << rem_ret_fn('comptime_zero', ast.Expr(ast.ComptimeExpr{
        expr: rem_num('1')
    }))
    stmts << rem_ret_fn('generic_index_zero', ast.Expr(ast.GenericArgOrIndexExpr{
        lhs:  rem_ident('foo')
        expr: rem_ident('int')
    }))
    stmts << rem_ret_fn('generic_args_zero', ast.Expr(ast.GenericArgs{
        lhs:  rem_ident('foo')
        args: [rem_ident('int')]
    }))
    stmts << rem_ret_fn('lambda_zero', ast.Expr(ast.LambdaExpr{
        args: [ast.Ident{
            name: 'x'
        }]
        expr: rem_num('1')
    }))
    stmts << rem_ret_fn('lifetime_zero', ast.Expr(ast.LifetimeExpr{
        name: 'a'
    }))
    stmts << rem_ret_fn('lock_zero', ast.Expr(ast.LockExpr{
        lock_exprs: [rem_ident('x')]
    }))
    stmts << rem_ret_fn('select_zero', ast.Expr(ast.SelectExpr{
        stmt: ast.empty_stmt
        next: ast.empty_expr
    }))
    stmts << rem_ret_fn('sql_zero', ast.Expr(ast.SqlExpr{
        expr:       rem_ident('db')
        table_name: 'User'
    }))
    return [
        ast.File{
            name:  'main.v'
            mod:   'main'
            stmts: stmts
        },
    ]
}

fn build_remaining_via_legacy(files []ast.File, env &types.Environment, name string) &Module {
    mut mod := Module.new(name)
    mut b := Builder.new_with_env(mod, env)
    b.register_fn_signatures(files[0])
    b.build_fn_bodies(files[0])
    return mod
}

fn build_remaining_via_flat(files []ast.File, env &types.Environment, name string) &Module {
    flat := ast.flatten_files(files)
    mut mod := Module.new(name)
    mut b := Builder.new_with_env(mod, env)
    b.register_fn_signatures_from_flat(flat.file_cursor(0))
    b.build_fn_bodies_from_flat(flat.file_cursor(0))
    return mod
}

fn test_build_remaining_exprs_from_flat_match_legacy() {
    _ = token.Token.dotdot
    files := make_remaining_expr_fixture()
    env := types.Environment.new()
    mod_legacy := build_remaining_via_legacy(files, env, 'remaining_legacy')
    mod_flat := build_remaining_via_flat(files, env, 'remaining_flat')

    assert mod_legacy.funcs.len == mod_flat.funcs.len
    assert mod_legacy.blocks.len == mod_flat.blocks.len
    assert mod_legacy.instrs.len == mod_flat.instrs.len
    assert mod_legacy.values.len == mod_flat.values.len
}