; E04-S05: compile hello.n8 and emit a runnable PRG (x128).
;
; The fixture runs in the compiler mapping, loads HELLO.N8, parses and
; type-checks it normally, and reads the single string print captured during
; pass 2. It then writes HELLO.PRG with output.s: the standard BASIC stub at
; $1C01 and a body at $1C0D that saves CR, selects the D129 mapping ($0E),
; prints the captured bytes through CHROUT, restores CR, and returns to BASIC.
;
; This is a bounded source-to-code proof, not the general statement emitter:
; one string print is required and gen_bad rejects anything else.
;
; Mailbox data: +0 diagnostics, +1 print count, +2 gen_bad, +3 text length,
; +4 out_err. FAIL code is the stage: 1 load, 2 diagnostics, 3 unsupported
; print, 4 output.

.setcpu "6502"
.include "../../src/common/c128.inc"
.include "../../src/common/mailbox.inc"
.include "../../src/common/formats.inc"

.import mmu_init, mmu_bank0, mmu_shutdown
.import src_load, src_dos_code, src_kernal_err
.import names_init
.import diag_init, diag_finish, diag_screen
.import parse_file, gen_text, gen_text_len, gen_print_count, gen_bad
.import out_begin, out_section, out_end_section
.import out_byte, out_bytes, out_finish, out_abort
.import out_load, out_entry, out_start, out_err
.import gen_stub

; A conditional branch to a far error path: near branch over an absolute JMP.
.macro ON_CARRY target
        bcc :+
        jmp target
:
.endmacro

.segment "LOADADDR"
        .word $1C01

.segment "EXEHDR"
        .word basic_end
        .word 10
        .byte $9E
        .byte "7181"
        .byte $00
basic_end:
        .word $0000

.segment "MAILBOX"
        .res MB_SIZE

.segment "STARTUP"
.export test_entry
test_entry:
        php
        sei
        ldx #MB_SIZE - 1
        lda #$00
@clr:   sta MB_BASE,x
        dex
        bpl @clr
        lda #MB_MAGIC0_VALUE
        sta MB_MAGIC0
        lda #MB_MAGIC1_VALUE
        sta MB_MAGIC1
        lda #MB_PROD_COMPILER
        sta MB_PRODUCER
        lda #MB_ST_RUNNING
        sta MB_STATUS
        lda #$00
        sta MB_DATA
        sta MB_DATA+1
        sta MB_DATA+2
        sta MB_DATA+3
        sta MB_DATA+4
        sta MB_DATA+5
        sta MB_DATA+6
        sta MB_DATA+7

        jsr mmu_init
        jsr mmu_bank0

        lda #<PRG_LOAD_ADDR
        sta out_load
        lda #>PRG_LOAD_ADDR
        sta out_load+1
        lda #<PRG_ENTRY_ADDR
        sta out_entry
        lda #>PRG_ENTRY_ADDR
        sta out_entry+1

        lda #<name_src
        ldx #>name_src
        ldy #name_src_len
        jsr src_load
        cmp #$00
        bne @fail_load

        jsr names_init
        lda #<name_src
        ldx #>name_src
        ldy #name_src_len
        jsr diag_init
        lda #$00                   ; ERR files only; keep the screen quiet
        sta diag_screen
        jsr parse_file
        jsr diag_finish
        sta diag_count

        lda diag_count
        sta MB_DATA+0
        lda gen_print_count
        sta MB_DATA+1
        lda gen_bad
        sta MB_DATA+2
        lda gen_text_len
        sta MB_DATA+3

        lda diag_count
        bne @fail_diag
        lda gen_bad
        bne @fail_gen
        lda gen_print_count
        cmp #1
        bne @fail_gen
        lda gen_text_len
        beq @fail_gen

        jsr emit_hello
        bcc @ok
        lda emit_err
        sta MB_DATA+4
        lda #4
        jmp @fail
@ok:    lda out_err
        sta MB_DATA+4
        lda #MB_ST_PASS
        sta MB_STATUS
        jmp @done
@fail_load:
        sta MB_DATA+5             ; src_load result
        lda src_dos_code
        sta MB_DATA+6
        lda src_kernal_err
        sta MB_DATA+7
        lda #1
        jmp @fail
@fail_diag:
        lda #2
        jmp @fail
@fail_gen:
        lda #3
@fail:  sta MB_CODE
        lda #$00
        sta MB_CODE+1
        lda #MB_ST_FAIL
        sta MB_STATUS
@done:  jsr mmu_shutdown
        plp
        rts

; Write HELLO.PRG through output.s. C=1 on any output error.
emit_hello:
        lda #<name_hello
        ldx #>name_hello
        ldy #name_hello_len
        jsr out_begin
        ON_CARRY @abort

        lda #<PRG_LOAD_ADDR        ; BASIC stub section
        sta out_start
        lda #>PRG_LOAD_ADDR
        sta out_start+1
        lda #<sec_stub
        ldx #>sec_stub
        ldy #4
        jsr out_section
        ON_CARRY @abort
        lda #<gen_stub
        ldx #>gen_stub
        ldy #PRG_STUB_SIZE
        jsr out_bytes
        ON_CARRY @abort
        jsr out_end_section
        ON_CARRY @abort

        lda #<PRG_ENTRY_ADDR       ; generated body
        sta out_start
        lda #>PRG_ENTRY_ADDR
        sta out_start+1
        lda #<sec_code
        ldx #>sec_code
        ldy #4
        jsr out_section
        ON_CARRY @abort
        lda #<prologue
        ldx #>prologue
        ldy #prologue_len
        jsr out_bytes
        ON_CARRY @abort

        ldy #$00
@chars: cpy gen_text_len
        beq @epilogue
        sty temp_y
        lda #$A9                   ; LDA #char
        jsr out_byte
        ON_CARRY @abort
        ldy temp_y
        lda gen_text,y
        jsr out_byte
        ON_CARRY @abort
        lda #$20                   ; JSR $FFD2 (CHROUT)
        jsr out_byte
        ON_CARRY @abort
        lda #$D2
        jsr out_byte
        ON_CARRY @abort
        lda #$FF
        jsr out_byte
        ON_CARRY @abort
        ldy temp_y
        iny
        bne @chars

@epilogue:
        lda #<epilogue
        ldx #>epilogue
        ldy #epilogue_len
        jsr out_bytes
        ON_CARRY @abort
        jsr out_end_section
        ON_CARRY @abort
        jsr out_finish
        ON_CARRY @abort
        clc
        rts
@abort: lda out_err
        sta emit_err
        jsr out_abort
        sec
        rts

.segment "RODATA"
name_src:       .byte "HELLO.N8"
name_src_len = * - name_src
name_hello:     .byte "HELLO"
name_hello_len = * - name_hello
sec_stub:       .byte "STUB"
sec_code:       .byte "CODE"

; LDA MMU_CR / PHA / LDA #$0E / STA MMU_CR
prologue:
        .byte $AD, $00, $FF, $48, $A9, $0E, $8D, $00, $FF
prologue_len = * - prologue
; PLA / STA MMU_CR / RTS
epilogue:
        .byte $68, $8D, $00, $FF, $60
epilogue_len = * - epilogue

.segment "BSS"
diag_count: .res 1
temp_y:     .res 1
emit_err:   .res 1