#include "test_utils.h"
#include "codegen.h"
#include "ast.h"
#include "arena.h"
#include <llvm-c/Analysis.h>

void test_codegen_simple_function() {
    Arena a = arena_create(1);

    // 构造 AST: fn main() -> i64 { return 42; }
    AstNode* ret = ast_make_return(&a, ast_make_literal_i64(&a, 42, loc_at(1, 1)), loc_at(1, 1));
    AstNode* stmts[] = { ret };
    AstNode* body = ast_make_block(&a, stmts, 1, loc_at(1, 1));
    AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
    AstNode* fns[] = { fn };
    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, loc_at(1, 1));

    const char* err = NULL;
    LLVMContextRef ctx = NULL;
    LLVMModuleRef mod = codegen_module(prog, &a, "test_mod", &err, &ctx);
    ASSERT(mod != NULL);
    ASSERT(err == NULL);

    // 验证模块
    char* verify_err = NULL;
    int failed = LLVMVerifyModule(mod, LLVMReturnStatusAction, &verify_err);
    ASSERT(!failed);

    LLVMDisposeModule(mod);
    LLVMContextDispose(ctx);
    arena_destroy(&a);
}

void test_codegen_if_else() {
    Arena a = arena_create(1);

    // fn main() -> i64 { if true { return 1; } else { return 0; } }
    AstNode* then_ret = ast_make_return(&a, ast_make_literal_i64(&a, 1, loc_at(1, 1)), loc_at(1, 1));
    AstNode* then_stmts[] = { then_ret };
    AstNode* then_block = ast_make_block(&a, then_stmts, 1, loc_at(1, 1));
    AstNode* else_ret = ast_make_return(&a, ast_make_literal_i64(&a, 0, loc_at(1, 1)), loc_at(1, 1));
    AstNode* else_stmts[] = { else_ret };
    AstNode* else_block = ast_make_block(&a, else_stmts, 1, loc_at(1, 1));
    AstNode* if_stmt = ast_make_if(&a,
        ast_make_literal_bool(&a, true, loc_at(1, 1)), then_block, else_block, loc_at(1, 1));
    AstNode* stmts[] = { if_stmt };
    AstNode* body = ast_make_block(&a, stmts, 1, loc_at(1, 1));
    AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
    AstNode* fns[] = { fn };
    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, loc_at(1, 1));

    const char* err = NULL;
    LLVMContextRef ctx2 = NULL;
    LLVMModuleRef mod = codegen_module(prog, &a, "test_mod2", &err, &ctx2);
    ASSERT(mod != NULL);

    char* verify_err = NULL;
    int failed = LLVMVerifyModule(mod, LLVMReturnStatusAction, &verify_err);
    ASSERT(!failed);

    LLVMDisposeModule(mod);
    LLVMContextDispose(ctx2);
    arena_destroy(&a);
}

void test_codegen_binary_ops() {
    Arena a = arena_create(1);

    // fn main() -> i64 { return 1 + 2 * 3; }
    AstNode* expr = ast_make_binary(&a, OP_ADD,
        ast_make_literal_i64(&a, 1, loc_at(1, 1)),
        ast_make_binary(&a, OP_MUL,
            ast_make_literal_i64(&a, 2, loc_at(1, 1)),
            ast_make_literal_i64(&a, 3, loc_at(1, 1)), loc_at(1, 1)),
        loc_at(1, 1));
    AstNode* ret = ast_make_return(&a, expr, loc_at(1, 1));
    AstNode* stmts[] = { ret };
    AstNode* body = ast_make_block(&a, stmts, 1, loc_at(1, 1));
    AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
    AstNode* fns[] = { fn };
    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, loc_at(1, 1));

    const char* err = NULL;
    LLVMContextRef ctx3 = NULL;
    LLVMModuleRef mod = codegen_module(prog, &a, "test_mod3", &err, &ctx3);
    ASSERT(mod != NULL);

    char* verify_err = NULL;
    int failed = LLVMVerifyModule(mod, LLVMReturnStatusAction, &verify_err);
    ASSERT(!failed);

    LLVMDisposeModule(mod);
    LLVMContextDispose(ctx3);
    arena_destroy(&a);
}

void test_codegen_while_loop() {
    Arena a = arena_create(1);
    // fn main() -> i64 { while true { return 0; } return 1; }
    AstNode* while_body_stmts[] = {
        ast_make_return(&a, ast_make_literal_i64(&a, 0, loc_at(1, 1)), loc_at(1, 1))
    };
    AstNode* while_body = ast_make_block(&a, while_body_stmts, 1, loc_at(1, 1));
    AstNode* while_stmt = ast_make_while(&a,
        ast_make_literal_bool(&a, true, loc_at(1, 1)), while_body, loc_at(1, 1));
    AstNode* ret = ast_make_return(&a, ast_make_literal_i64(&a, 1, loc_at(1, 1)), loc_at(1, 1));
    AstNode* stmts[] = { while_stmt, ret };
    AstNode* fn_body = ast_make_block(&a, stmts, 2, loc_at(1, 1));
    AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, fn_body, loc_at(1, 1));
    AstNode* fns[] = { fn };
    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, loc_at(1, 1));

    const char* err = NULL;
    LLVMContextRef ctx4 = NULL;
    LLVMModuleRef mod = codegen_module(prog, &a, "test_while", &err, &ctx4);
    ASSERT(mod != NULL);
    char* verify_err = NULL;
    ASSERT(!LLVMVerifyModule(mod, LLVMReturnStatusAction, &verify_err));
    LLVMDisposeModule(mod);
    LLVMContextDispose(ctx4);
    arena_destroy(&a);
}

/* === struct IR 生成测试 === */

void test_codegen_struct_decl() {
    Arena a = arena_create(1);

    /* 构造 AST: struct Point { x: i64, y: i64 } */
    AstNode* fields[2];
    fields[0] = ast_make_parameter(&a, "x", TYPE_I64, NULL, loc_at(1, 1));
    fields[1] = ast_make_parameter(&a, "y", TYPE_I64, NULL, loc_at(1, 1));
    AstNode* struct_decl = ast_make_struct_decl(&a, "Point", fields, 2, loc_at(1, 1));
    AstNode* structs[] = { struct_decl };

    /* 构造 fn main() -> i64 { let p = Point { x: 1, y: 2 }; return p.x; } */
    const char* fnames[] = {"x", "y"};
    AstNode* fvals[] = {
        ast_make_literal_i64(&a, 1, loc_at(1, 1)),
        ast_make_literal_i64(&a, 2, loc_at(1, 1))
    };
    AstNode* init = ast_make_struct_init(&a, "Point", fnames, fvals, 2, loc_at(1, 1));
    /* 手动设置类型（绕过 sema，codegen 需要读取 type 字段） */
    init->type.kind = TYPE_STRUCT;
    init->type.struct_name = "Point";

    AstNode* let_stmt = ast_make_let(&a, "p", TYPE_UNKNOWN, false, false,
                                     init, NULL, loc_at(1, 1));

    /* return p.x; */
    AstNode* p_ident = ast_make_ident(&a, "p", loc_at(1, 1));
    p_ident->type.kind = TYPE_STRUCT;
    p_ident->type.struct_name = "Point";

    AstNode* field_x = ast_make_field_access(&a, p_ident, "x", loc_at(1, 1));
    field_x->as.field_access.field_index = 0;  /* x 是第 0 个字段 */
    field_x->type.kind = TYPE_I64;

    AstNode* ret = ast_make_return(&a, field_x, loc_at(1, 1));
    AstNode* stmts[] = { let_stmt, ret };
    AstNode* body = ast_make_block(&a, stmts, 2, loc_at(1, 1));
    AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
    AstNode* fns[] = { fn };

    AstNode* prog = ast_make_program(&a, fns, 1, structs, 1, NULL, 0, loc_at(1, 1));

    const char* err = NULL;
    LLVMContextRef ctx = NULL;
    LLVMModuleRef mod = codegen_module(prog, &a, "test_struct_decl", &err, &ctx);
    ASSERT(mod != NULL);
    ASSERT(err == NULL);

    char* verify_err = NULL;
    int failed = LLVMVerifyModule(mod, LLVMReturnStatusAction, &verify_err);
    ASSERT(!failed);

    LLVMDisposeModule(mod);
    LLVMContextDispose(ctx);
    arena_destroy(&a);
}

void test_codegen_struct_field_access() {
    Arena a = arena_create(1);

    /* 构造 AST: struct Point { x: i64, y: i64 } */
    AstNode* fields[2];
    fields[0] = ast_make_parameter(&a, "x", TYPE_I64, NULL, loc_at(1, 1));
    fields[1] = ast_make_parameter(&a, "y", TYPE_I64, NULL, loc_at(1, 1));
    AstNode* struct_decl = ast_make_struct_decl(&a, "Point", fields, 2, loc_at(1, 1));
    AstNode* structs[] = { struct_decl };

    /* 构造 fn main() -> i64 { let p = Point { x: 5, y: 10 }; return p.y; } */
    const char* fnames[] = {"x", "y"};
    AstNode* fvals[] = {
        ast_make_literal_i64(&a, 5, loc_at(1, 1)),
        ast_make_literal_i64(&a, 10, loc_at(1, 1))
    };
    AstNode* init = ast_make_struct_init(&a, "Point", fnames, fvals, 2, loc_at(1, 1));
    init->type.kind = TYPE_STRUCT;
    init->type.struct_name = "Point";

    AstNode* let_stmt = ast_make_let(&a, "p", TYPE_UNKNOWN, false, false,
                                     init, NULL, loc_at(1, 1));

    /* return p.y; */
    AstNode* p_ident = ast_make_ident(&a, "p", loc_at(1, 1));
    p_ident->type.kind = TYPE_STRUCT;
    p_ident->type.struct_name = "Point";

    AstNode* field_y = ast_make_field_access(&a, p_ident, "y", loc_at(1, 1));
    field_y->as.field_access.field_index = 1;  /* y 是第 1 个字段 */
    field_y->type.kind = TYPE_I64;

    AstNode* ret = ast_make_return(&a, field_y, loc_at(1, 1));
    AstNode* stmts[] = { let_stmt, ret };
    AstNode* body = ast_make_block(&a, stmts, 2, loc_at(1, 1));
    AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
    AstNode* fns[] = { fn };

    AstNode* prog = ast_make_program(&a, fns, 1, structs, 1, NULL, 0, loc_at(1, 1));

    const char* err = NULL;
    LLVMContextRef ctx = NULL;
    LLVMModuleRef mod = codegen_module(prog, &a, "test_struct_field", &err, &ctx);
    ASSERT(mod != NULL);
    ASSERT(err == NULL);

    char* verify_err = NULL;
    int failed = LLVMVerifyModule(mod, LLVMReturnStatusAction, &verify_err);
    ASSERT(!failed);

    LLVMDisposeModule(mod);
    LLVMContextDispose(ctx);
    arena_destroy(&a);
}

int main(void) {
    TEST_RUN(test_codegen_simple_function);
    TEST_RUN(test_codegen_if_else);
    TEST_RUN(test_codegen_binary_ops);
    TEST_RUN(test_codegen_while_loop);
    TEST_RUN(test_codegen_struct_decl);
    TEST_RUN(test_codegen_struct_field_access);
    return test_summary();
}